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3e082978c33151d576694deac8abde021ea669a8
50486 Commits
| Author | SHA1 | Message | Date | |
|---|---|---|---|---|
Andy Shevchenko
|
84dfce65a7 |
x86/bugs: Remove dead code which might prevent from building
Clang, in particular, is not happy about dead code:
arch/x86/kernel/cpu/bugs.c:1830:20: error: unused function 'match_option' [-Werror,-Wunused-function]
1830 | static inline bool match_option(const char *arg, int arglen, const char *opt)
| ^~~~~~~~~~~~
1 error generated.
Remove a leftover from the previous cleanup.
Fixes:
|
||
|
David Kaplan
|
204ced4108 |
x86/bugs: Qualify RETBLEED_INTEL_MSG
When retbleed mitigation is disabled, the kernel already prints an info
message that the system is vulnerable. Recent code restructuring also
inadvertently led to RETBLEED_INTEL_MSG being printed as an error, which is
unnecessary as retbleed mitigation was already explicitly disabled (by config
option, cmdline, etc.).
Qualify this print statement so the warning is not printed unless an actual
retbleed mitigation was selected and is being disabled due to incompatibility
with spectre_v2.
Fixes:
|
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|
Andrew Cooper
|
876f0d43af |
x86/microcode: Fix Entrysign revision check for Zen1/Naples
... to match AMD's statement here:
https://www.amd.com/en/resources/product-security/bulletin/amd-sb-7033.html
Fixes:
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|
Babu Moger
|
19de7113bf |
x86,fs/resctrl: Fix NULL pointer dereference with events force-disabled in mbm_event mode
The following NULL pointer dereference is encountered on mount of resctrl fs
after booting a system that supports assignable counters with the
"rdt=!mbmtotal,!mbmlocal" kernel parameters:
BUG: kernel NULL pointer dereference, address: 0000000000000008
RIP: 0010:mbm_cntr_get
Call Trace:
rdtgroup_assign_cntr_event
rdtgroup_assign_cntrs
rdt_get_tree
Specifying the kernel parameter "rdt=!mbmtotal,!mbmlocal" effectively disables
the legacy X86_FEATURE_CQM_MBM_TOTAL and X86_FEATURE_CQM_MBM_LOCAL features
and the MBM events they represent. This results in the per-domain MBM event
related data structures to not be allocated during early initialization.
resctrl fs initialization follows by implicitly enabling both MBM total and
local events on a system that supports assignable counters (mbm_event mode),
but this enabling occurs after the per-domain data structures have been
created.
After booting, resctrl fs assumes that an enabled event can access all its
state. This results in NULL pointer dereference when resctrl attempts to
access the un-allocated structures of an enabled event.
Remove the late MBM event enabling from resctrl fs.
This leaves a problem where the X86_FEATURE_CQM_MBM_TOTAL and
X86_FEATURE_CQM_MBM_LOCAL features may be disabled while assignable counter
(mbm_event) mode is enabled without any events to support. Switching between
the "default" and "mbm_event" mode without any events is not practical.
Create a dependency between the X86_FEATURE_{CQM_MBM_TOTAL,CQM_MBM_LOCAL} and
X86_FEATURE_ABMC (assignable counter) hardware features. An x86 system that
supports assignable counters now requires support of X86_FEATURE_CQM_MBM_TOTAL
or X86_FEATURE_CQM_MBM_LOCAL.
This ensures all needed MBM related data structures are created before use and
that it is only possible to switch between "default" and "mbm_event" mode when
the same events are available in both modes. This dependency does not exist in
the hardware but this usage of these feature settings work for known systems.
[ bp: Massage commit message. ]
Fixes:
|
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|
Linus Torvalds
|
c7864eeaa4 |
Merge tag 'x86_urgent_for_v6.18_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Borislav Petkov: - Reset the why-the-system-rebooted register on AMD to avoid stale bits remaining from previous boots - Add a missing barrier in the TLB flushing code to prevent erroneously not flushing a TLB generation - Make sure cpa_flush() does not overshoot when computing the end range of a flush region - Fix resctrl bandwidth counting on AMD systems when the amount of monitoring groups created exceeds the number the hardware can track * tag 'x86_urgent_for_v6.18_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/CPU/AMD: Prevent reset reasons from being retained across reboot x86/mm: Fix SMP ordering in switch_mm_irqs_off() x86/mm: Fix overflow in __cpa_addr() x86/resctrl: Fix miscount of bandwidth event when reactivating previously unavailable RMID |
||
|
Paolo Bonzini
|
4361f5aa8b |
Merge tag 'kvm-x86-fixes-6.18-rc2' of https://github.com/kvm-x86/linux into HEAD
KVM x86 fixes for 6.18:
- Expand the KVM_PRE_FAULT_MEMORY selftest to add a regression test for the
bug fixed by commit
|
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|
Rong Zhang
|
e6416c2dfe |
x86/CPU/AMD: Prevent reset reasons from being retained across reboot
The S5_RESET_STATUS register is parsed on boot and printed to kmsg.
However, this could sometimes be misleading and lead to users wasting a
lot of time on meaningless debugging for two reasons:
* Some bits are never cleared by hardware. It's the software's
responsibility to clear them as per the Processor Programming Reference
(see [1]).
* Some rare hardware-initiated platform resets do not update the
register at all.
In both cases, a previous reboot could leave its trace in the register,
resulting in users seeing unrelated reboot reasons while debugging random
reboots afterward.
Write the read value back to the register in order to clear all reason bits
since they are write-1-to-clear while the others must be preserved.
[1]: https://bugzilla.kernel.org/show_bug.cgi?id=206537#attach_303991
[ bp: Massage commit message. ]
Fixes:
|
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|
Ingo Molnar
|
83b0177a6c |
x86/mm: Fix SMP ordering in switch_mm_irqs_off()
Stephen noted that it is possible to not have an smp_mb() between
the loaded_mm store and the tlb_gen load in switch_mm(), meaning the
ordering against flush_tlb_mm_range() goes out the window, and it
becomes possible for switch_mm() to not observe a recent tlb_gen
update and fail to flush the TLBs.
[ dhansen: merge conflict fixed by Ingo ]
Fixes:
|
||
|
Rik van Riel
|
f25785f9b0 |
x86/mm: Fix overflow in __cpa_addr()
The change to have cpa_flush() call flush_kernel_pages() introduced
a bug where __cpa_addr() can access an address one larger than the
largest one in the cpa->pages array.
KASAN reports the issue like this:
BUG: KASAN: slab-out-of-bounds in __cpa_addr arch/x86/mm/pat/set_memory.c:309 [inline]
BUG: KASAN: slab-out-of-bounds in __cpa_addr+0x1d3/0x220 arch/x86/mm/pat/set_memory.c:306
Read of size 8 at addr ffff88801f75e8f8 by task syz.0.17/5978
This bug could cause cpa_flush() to not properly flush memory,
which somehow never showed any symptoms in my tests, possibly
because cpa_flush() is called so rarely, but could potentially
cause issues for other people.
Fix the issue by directly calculating the flush end address
from the start address.
Fixes:
|
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|
Babu Moger
|
15292f1b4c |
x86/resctrl: Fix miscount of bandwidth event when reactivating previously unavailable RMID
Users can create as many monitoring groups as the number of RMIDs supported
by the hardware. However, on AMD systems, only a limited number of RMIDs
are guaranteed to be actively tracked by the hardware. RMIDs that exceed
this limit are placed in an "Unavailable" state.
When a bandwidth counter is read for such an RMID, the hardware sets
MSR_IA32_QM_CTR.Unavailable (bit 62). When such an RMID starts being tracked
again the hardware counter is reset to zero. MSR_IA32_QM_CTR.Unavailable
remains set on first read after tracking re-starts and is clear on all
subsequent reads as long as the RMID is tracked.
resctrl miscounts the bandwidth events after an RMID transitions from the
"Unavailable" state back to being tracked. This happens because when the
hardware starts counting again after resetting the counter to zero, resctrl
in turn compares the new count against the counter value stored from the
previous time the RMID was tracked.
This results in resctrl computing an event value that is either undercounting
(when new counter is more than stored counter) or a mistaken overflow (when
new counter is less than stored counter).
Reset the stored value (arch_mbm_state::prev_msr) of MSR_IA32_QM_CTR to
zero whenever the RMID is in the "Unavailable" state to ensure accurate
counting after the RMID resets to zero when it starts to be tracked again.
Example scenario that results in mistaken overflow
==================================================
1. The resctrl filesystem is mounted, and a task is assigned to a
monitoring group.
$mount -t resctrl resctrl /sys/fs/resctrl
$mkdir /sys/fs/resctrl/mon_groups/test1/
$echo 1234 > /sys/fs/resctrl/mon_groups/test1/tasks
$cat /sys/fs/resctrl/mon_groups/test1/mon_data/mon_L3_*/mbm_total_bytes
21323 <- Total bytes on domain 0
"Unavailable" <- Total bytes on domain 1
Task is running on domain 0. Counter on domain 1 is "Unavailable".
2. The task runs on domain 0 for a while and then moves to domain 1. The
counter starts incrementing on domain 1.
$cat /sys/fs/resctrl/mon_groups/test1/mon_data/mon_L3_*/mbm_total_bytes
7345357 <- Total bytes on domain 0
4545 <- Total bytes on domain 1
3. At some point, the RMID in domain 0 transitions to the "Unavailable"
state because the task is no longer executing in that domain.
$cat /sys/fs/resctrl/mon_groups/test1/mon_data/mon_L3_*/mbm_total_bytes
"Unavailable" <- Total bytes on domain 0
434341 <- Total bytes on domain 1
4. Since the task continues to migrate between domains, it may eventually
return to domain 0.
$cat /sys/fs/resctrl/mon_groups/test1/mon_data/mon_L3_*/mbm_total_bytes
17592178699059 <- Overflow on domain 0
3232332 <- Total bytes on domain 1
In this case, the RMID on domain 0 transitions from "Unavailable" state to
active state. The hardware sets MSR_IA32_QM_CTR.Unavailable (bit 62) when
the counter is read and begins tracking the RMID counting from 0.
Subsequent reads succeed but return a value smaller than the previously
saved MSR value (7345357). Consequently, the resctrl's overflow logic is
triggered, it compares the previous value (7345357) with the new, smaller
value and incorrectly interprets this as a counter overflow, adding a large
delta.
In reality, this is a false positive: the counter did not overflow but was
simply reset when the RMID transitioned from "Unavailable" back to active
state.
Here is the text from APM [1] available from [2].
"In PQOS Version 2.0 or higher, the MBM hardware will set the U bit on the
first QM_CTR read when it begins tracking an RMID that it was not
previously tracking. The U bit will be zero for all subsequent reads from
that RMID while it is still tracked by the hardware. Therefore, a QM_CTR
read with the U bit set when that RMID is in use by a processor can be
considered 0 when calculating the difference with a subsequent read."
[1] AMD64 Architecture Programmer's Manual Volume 2: System Programming
Publication # 24593 Revision 3.41 section 19.3.3 Monitoring L3 Memory
Bandwidth (MBM).
[ bp: Split commit message into smaller paragraph chunks for better
consumption. ]
Fixes:
|
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Linus Torvalds
|
9591fdb061 |
Merge tag 'x86_core_for_v6.18_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull more x86 updates from Borislav Petkov: - Remove a bunch of asm implementing condition flags testing in KVM's emulator in favor of int3_emulate_jcc() which is written in C - Replace KVM fastops with C-based stubs which avoids problems with the fastop infra related to latter not adhering to the C ABI due to their special calling convention and, more importantly, bypassing compiler control-flow integrity checking because they're written in asm - Remove wrongly used static branches and other ugliness accumulated over time in hyperv's hypercall implementation with a proper static function call to the correct hypervisor call variant - Add some fixes and modifications to allow running FRED-enabled kernels in KVM even on non-FRED hardware - Add kCFI improvements like validating indirect calls and prepare for enabling kCFI with GCC. Add cmdline params documentation and other code cleanups - Use the single-byte 0xd6 insn as the official #UD single-byte undefined opcode instruction as agreed upon by both x86 vendors - Other smaller cleanups and touchups all over the place * tag 'x86_core_for_v6.18_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (24 commits) x86,retpoline: Optimize patch_retpoline() x86,ibt: Use UDB instead of 0xEA x86/cfi: Remove __noinitretpoline and __noretpoline x86/cfi: Add "debug" option to "cfi=" bootparam x86/cfi: Standardize on common "CFI:" prefix for CFI reports x86/cfi: Document the "cfi=" bootparam options x86/traps: Clarify KCFI instruction layout compiler_types.h: Move __nocfi out of compiler-specific header objtool: Validate kCFI calls x86/fred: KVM: VMX: Always use FRED for IRQs when CONFIG_X86_FRED=y x86/fred: Play nice with invoking asm_fred_entry_from_kvm() on non-FRED hardware x86/fred: Install system vector handlers even if FRED isn't fully enabled x86/hyperv: Use direct call to hypercall-page x86/hyperv: Clean up hv_do_hypercall() KVM: x86: Remove fastops KVM: x86: Convert em_salc() to C KVM: x86: Introduce EM_ASM_3WCL KVM: x86: Introduce EM_ASM_1SRC2 KVM: x86: Introduce EM_ASM_2CL KVM: x86: Introduce EM_ASM_2W ... |
||
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Linus Torvalds
|
2f0a750453 |
Merge tag 'x86_cleanups_for_v6.18_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 cleanups from Borislav Petkov: - Simplify inline asm flag output operands now that the minimum compiler version supports the =@ccCOND syntax - Remove a bunch of AS_* Kconfig symbols which detect assembler support for various instruction mnemonics now that the minimum assembler version supports them all - The usual cleanups all over the place * tag 'x86_cleanups_for_v6.18_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/asm: Remove code depending on __GCC_ASM_FLAG_OUTPUTS__ x86/sgx: Use ENCLS mnemonic in <kernel/cpu/sgx/encls.h> x86/mtrr: Remove license boilerplate text with bad FSF address x86/asm: Use RDPKRU and WRPKRU mnemonics in <asm/special_insns.h> x86/idle: Use MONITORX and MWAITX mnemonics in <asm/mwait.h> x86/entry/fred: Push __KERNEL_CS directly x86/kconfig: Remove CONFIG_AS_AVX512 crypto: x86 - Remove CONFIG_AS_VPCLMULQDQ crypto: X86 - Remove CONFIG_AS_VAES crypto: x86 - Remove CONFIG_AS_GFNI x86/kconfig: Drop unused and needless config X86_64_SMP |
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Sean Christopherson
|
44c6cb9fe9 |
KVM: guest_memfd: Allow mmap() on guest_memfd for x86 VMs with private memory
Allow mmap() on guest_memfd instances for x86 VMs with private memory as
the need to track private vs. shared state in the guest_memfd instance is
only pertinent to INIT_SHARED. Doing mmap() on private memory isn't
terrible useful (yet!), but it's now possible, and will be desirable when
guest_memfd gains support for other VMA-based syscalls, e.g. mbind() to
set NUMA policy.
Lift the restriction now, before MMAP support is officially released, so
that KVM doesn't need to add another capability to enumerate support for
mmap() on private memory.
Fixes:
|
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Dapeng Mi
|
034417c143 |
KVM: x86/pmu: Don't try to get perf capabilities for hybrid CPUs
Explicitly zero kvm_host_pmu instead of attempting to get the perf PMU
capabilities when running on a hybrid CPU to avoid running afoul of perf's
sanity check.
------------[ cut here ]------------
WARNING: arch/x86/events/core.c:3089 at perf_get_x86_pmu_capability+0xd/0xc0,
Call Trace:
<TASK>
kvm_x86_vendor_init+0x1b0/0x1a40 [kvm]
vmx_init+0xdb/0x260 [kvm_intel]
vt_init+0x12/0x9d0 [kvm_intel]
do_one_initcall+0x60/0x3f0
do_init_module+0x97/0x2b0
load_module+0x2d08/0x2e30
init_module_from_file+0x96/0xe0
idempotent_init_module+0x117/0x330
__x64_sys_finit_module+0x73/0xe0
Always read the capabilities for non-hybrid CPUs, i.e. don't entirely
revert to reading capabilities if and only if KVM wants to use a PMU, as
it may be useful to have the host PMU capabilities available, e.g. if only
or debug.
Reported-by: Chaitanya Kumar Borah <chaitanya.kumar.borah@intel.com>
Closes: https://lore.kernel.org/all/70b64347-2aca-4511-af78-a767d5fa8226@intel.com/
Fixes:
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Linus Torvalds
|
89b59f0979 |
Merge tag 'acpi-6.18-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull more ACPI updates from Rafael Wysocki:
"These fix a driver bug, clean up two pieces of code and improve the
fwnode API consistency:
- Add missing synchronization between interface updates in the ACPI
battery driver (Rafael Wysocki)
- Remove open coded check for cpu_feature_enabled() from
acpi_processor_power_init_bm_check() (Mario Limonciello)
- Remove redundant rcu_read_lock/unlock() under spinlock from
ghes_notify_hed() in the ACPI APEI support code (pengdonglin)
- Make the .get_next_child_node() callback in the ACPI fwnode backend
skip ACPI devices that are not present for consistency with the
analogous callback in the OF fwnode backend (Sakari Ailus)"
* tag 'acpi-6.18-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
ACPI: property: Return present device nodes only on fwnode interface
ACPI: APEI: Remove redundant rcu_read_lock/unlock() under spinlock
ACPI: battery: Add synchronization between interface updates
x86/acpi/cstate: Remove open coded check for cpu_feature_enabled()
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Linus Torvalds
|
2215336295 |
Merge tag 'hyperv-next-signed-20251006' of git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux
Pull hyperv updates from Wei Liu: - Unify guest entry code for KVM and MSHV (Sean Christopherson) - Switch Hyper-V MSI domain to use msi_create_parent_irq_domain() (Nam Cao) - Add CONFIG_HYPERV_VMBUS and limit the semantics of CONFIG_HYPERV (Mukesh Rathor) - Add kexec/kdump support on Azure CVMs (Vitaly Kuznetsov) - Deprecate hyperv_fb in favor of Hyper-V DRM driver (Prasanna Kumar T S M) - Miscellaneous enhancements, fixes and cleanups (Abhishek Tiwari, Alok Tiwari, Nuno Das Neves, Wei Liu, Roman Kisel, Michael Kelley) * tag 'hyperv-next-signed-20251006' of git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux: hyperv: Remove the spurious null directive line MAINTAINERS: Mark hyperv_fb driver Obsolete fbdev/hyperv_fb: deprecate this in favor of Hyper-V DRM driver Drivers: hv: Make CONFIG_HYPERV bool Drivers: hv: Add CONFIG_HYPERV_VMBUS option Drivers: hv: vmbus: Fix typos in vmbus_drv.c Drivers: hv: vmbus: Fix sysfs output format for ring buffer index Drivers: hv: vmbus: Clean up sscanf format specifier in target_cpu_store() x86/hyperv: Switch to msi_create_parent_irq_domain() mshv: Use common "entry virt" APIs to do work in root before running guest entry: Rename "kvm" entry code assets to "virt" to genericize APIs entry/kvm: KVM: Move KVM details related to signal/-EINTR into KVM proper mshv: Handle NEED_RESCHED_LAZY before transferring to guest x86/hyperv: Add kexec/kdump support on Azure CVMs Drivers: hv: Simplify data structures for VMBus channel close message Drivers: hv: util: Cosmetic changes for hv_utils_transport.c mshv: Add support for a new parent partition configuration clocksource: hyper-v: Skip unnecessary checks for the root partition hyperv: Add missing field to hv_output_map_device_interrupt |
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Rafael J. Wysocki
|
dd68fd72e5 |
Merge branches 'acpi-x86', 'acpi-battery', 'acpi-apei' and 'acpi-property'
Merge an x86 cleanup related to ACPI, an ACPI battery driver fix, an ACPI APEI cleanup, and an ACPI device properties handling update for 6.18-rc1: - Remove open coded check for cpu_feature_enabled() from acpi_processor_power_init_bm_check() (Mario Limonciello) - Add missing synchronization between interface updates in the ACPI battery driver (Rafael Wysocki) - Remove redundant rcu_read_lock/unlock() under spinlock from ghes_notify_hed() in the ACPI APEI support code (pengdonglin) - Make the .get_next_child_node() callback in the ACPI fwnode backend skip ACPI devices that are not present for consistency with the analogous callback in the OF fwnode backend (Sakari Ailus) * acpi-x86: x86/acpi/cstate: Remove open coded check for cpu_feature_enabled() * acpi-battery: ACPI: battery: Add synchronization between interface updates * acpi-apei: ACPI: APEI: Remove redundant rcu_read_lock/unlock() under spinlock * acpi-property: ACPI: property: Return present device nodes only on fwnode interface |
||
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Linus Torvalds
|
256e341706 |
Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull x86 kvm updates from Paolo Bonzini:
"Generic:
- Rework almost all of KVM's exports to expose symbols only to KVM's
x86 vendor modules (kvm-{amd,intel}.ko and PPC's kvm-{pr,hv}.ko
x86:
- Rework almost all of KVM x86's exports to expose symbols only to
KVM's vendor modules, i.e. to kvm-{amd,intel}.ko
- Add support for virtualizing Control-flow Enforcement Technology
(CET) on Intel (Shadow Stacks and Indirect Branch Tracking) and AMD
(Shadow Stacks).
It is worth noting that while SHSTK and IBT can be enabled
separately in CPUID, it is not really possible to virtualize them
separately. Therefore, Intel processors will really allow both
SHSTK and IBT under the hood if either is made visible in the
guest's CPUID. The alternative would be to intercept
XSAVES/XRSTORS, which is not feasible for performance reasons
- Fix a variety of fuzzing WARNs all caused by checking L1 intercepts
when completing userspace I/O. KVM has already committed to
allowing L2 to to perform I/O at that point
- Emulate PERF_CNTR_GLOBAL_STATUS_SET for PerfMonV2 guests, as the
MSR is supposed to exist for v2 PMUs
- Allow Centaur CPU leaves (base 0xC000_0000) for Zhaoxin CPUs
- Add support for the immediate forms of RDMSR and WRMSRNS, sans full
emulator support (KVM should never need to emulate the MSRs outside
of forced emulation and other contrived testing scenarios)
- Clean up the MSR APIs in preparation for CET and FRED
virtualization, as well as mediated vPMU support
- Clean up a pile of PMU code in anticipation of adding support for
mediated vPMUs
- Reject in-kernel IOAPIC/PIT for TDX VMs, as KVM can't obtain EOI
vmexits needed to faithfully emulate an I/O APIC for such guests
- Many cleanups and minor fixes
- Recover possible NX huge pages within the TDP MMU under read lock
to reduce guest jitter when restoring NX huge pages
- Return -EAGAIN during prefault if userspace concurrently
deletes/moves the relevant memslot, to fix an issue where
prefaulting could deadlock with the memslot update
x86 (AMD):
- Enable AVIC by default for Zen4+ if x2AVIC (and other prereqs) is
supported
- Require a minimum GHCB version of 2 when starting SEV-SNP guests
via KVM_SEV_INIT2 so that invalid GHCB versions result in immediate
errors instead of latent guest failures
- Add support for SEV-SNP's CipherText Hiding, an opt-in feature that
prevents unauthorized CPU accesses from reading the ciphertext of
SNP guest private memory, e.g. to attempt an offline attack. This
feature splits the shared SEV-ES/SEV-SNP ASID space into separate
ranges for SEV-ES and SEV-SNP guests, therefore a new module
parameter is needed to control the number of ASIDs that can be used
for VMs with CipherText Hiding vs. how many can be used to run
SEV-ES guests
- Add support for Secure TSC for SEV-SNP guests, which prevents the
untrusted host from tampering with the guest's TSC frequency, while
still allowing the the VMM to configure the guest's TSC frequency
prior to launch
- Validate the XCR0 provided by the guest (via the GHCB) to avoid
bugs resulting from bogus XCR0 values
- Save an SEV guest's policy if and only if LAUNCH_START fully
succeeds to avoid leaving behind stale state (thankfully not
consumed in KVM)
- Explicitly reject non-positive effective lengths during SNP's
LAUNCH_UPDATE instead of subtly relying on guest_memfd to deal with
them
- Reload the pre-VMRUN TSC_AUX on #VMEXIT for SEV-ES guests, not the
host's desired TSC_AUX, to fix a bug where KVM was keeping a
different vCPU's TSC_AUX in the host MSR until return to userspace
KVM (Intel):
- Preparation for FRED support
- Don't retry in TDX's anti-zero-step mitigation if the target
memslot is invalid, i.e. is being deleted or moved, to fix a
deadlock scenario similar to the aforementioned prefaulting case
- Misc bugfixes and minor cleanups"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (142 commits)
KVM: x86: Export KVM-internal symbols for sub-modules only
KVM: x86: Drop pointless exports of kvm_arch_xxx() hooks
KVM: x86: Move kvm_intr_is_single_vcpu() to lapic.c
KVM: Export KVM-internal symbols for sub-modules only
KVM: s390/vfio-ap: Use kvm_is_gpa_in_memslot() instead of open coded equivalent
KVM: VMX: Make CR4.CET a guest owned bit
KVM: selftests: Verify MSRs are (not) in save/restore list when (un)supported
KVM: selftests: Add coverage for KVM-defined registers in MSRs test
KVM: selftests: Add KVM_{G,S}ET_ONE_REG coverage to MSRs test
KVM: selftests: Extend MSRs test to validate vCPUs without supported features
KVM: selftests: Add support for MSR_IA32_{S,U}_CET to MSRs test
KVM: selftests: Add an MSR test to exercise guest/host and read/write
KVM: x86: Define AMD's #HV, #VC, and #SX exception vectors
KVM: x86: Define Control Protection Exception (#CP) vector
KVM: x86: Add human friendly formatting for #XM, and #VE
KVM: SVM: Enable shadow stack virtualization for SVM
KVM: SEV: Synchronize MSR_IA32_XSS from the GHCB when it's valid
KVM: SVM: Pass through shadow stack MSRs as appropriate
KVM: SVM: Update dump_vmcb with shadow stack save area additions
KVM: nSVM: Save/load CET Shadow Stack state to/from vmcb12/vmcb02
...
|
||
|
Linus Torvalds
|
fc282d1731 |
Merge tag 'uml-for-linux-6.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/uml/linux
Pull uml updates from Johannes Berg: - minor preparations for SMP support - SPARSE_IRQ support for kunit - help output cleanups * tag 'uml-for-linux-6.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/uml/linux: um: Remove unused ipi_pipe field from cpuinfo_um um: Remove unused cpu_data and current_cpu_data macros um: Stop tracking virtual CPUs via mm_cpumask() um: Centralize stub size calculations um: Remove outdated comment about STUB_DATA_PAGES um: Remove unused offset and child_err fields from stub_data um: Indent time-travel help messages um: Fix help message for ssl-non-raw um: vector: Fix indentation for help message um: Add missing trailing newline to help messages um: virtio-pci: implement .shutdown() um: Support SPARSE_IRQ |
||
|
Linus Torvalds
|
2f2c725493 |
Merge tag 'pci-v6.18-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/pci/pci
Pull pci updates from Bjorn Helgaas:
"Enumeration:
- Add PCI_FIND_NEXT_CAP() and PCI_FIND_NEXT_EXT_CAP() macros that
take config space accessor functions.
Implement pci_find_capability(), pci_find_ext_capability(), and
dwc, dwc endpoint, and cadence capability search interfaces with
them (Hans Zhang)
- Leave parent unit address 0 in 'interrupt-map' so that when we
build devicetree nodes to describe PCI functions that contain
multiple peripherals, we can build this property even when
interrupt controllers lack 'reg' properties (Lorenzo Pieralisi)
- Add a Xeon 6 quirk to disable Extended Tags and limit Max Read
Request Size to 128B to avoid a performance issue (Ilpo Järvinen)
- Add sysfs 'serial_number' file to expose the Device Serial Number
(Matthew Wood)
- Fix pci_acpi_preserve_config() memory leak (Nirmoy Das)
Resource management:
- Align m68k pcibios_enable_device() with other arches (Ilpo
Järvinen)
- Remove sparc pcibios_enable_device() implementations that don't do
anything beyond what pci_enable_resources() does (Ilpo Järvinen)
- Remove mips pcibios_enable_resources() and use
pci_enable_resources() instead (Ilpo Järvinen)
- Clean up bridge window sizing and assignment (Ilpo Järvinen),
including:
- Leave non-claimed bridge windows disabled
- Enable bridges even if a window wasn't assigned because not all
windows are required by downstream devices
- Preserve bridge window type when releasing the resource, since
the type is needed for reassignment
- Consolidate selection of bridge windows into two new
interfaces, pbus_select_window() and
pbus_select_window_for_type(), so this is done consistently
- Compute bridge window start and end earlier to avoid logging
stale information
MSI:
- Add quirk to disable MSI on RDC PCI to PCIe bridges (Marcos Del Sol
Vives)
Error handling:
- Align AER with EEH by allowing drivers to request a Bus Reset on
Non-Fatal Errors (in addition to the reset on Fatal Errors that we
already do) (Lukas Wunner)
- If error recovery fails, emit FAILED_RECOVERY uevents for the
devices, not for the bridge leading to them.
This makes them correspond to BEGIN_RECOVERY uevents (Lukas Wunner)
- Align AER with EEH by calling err_handler.error_detected()
callbacks to notify drivers if error recovery fails (Lukas Wunner)
- Align AER with EEH by restoring device error_state to
pci_channel_io_normal before the err_handler.slot_reset() callback.
This is earlier than before the err_handler.resume() callback
(Lukas Wunner)
- Emit a BEGIN_RECOVERY uevent when driver's
err_handler.error_detected() requests a reset, as well as when it
says recovery is complete or can be done without a reset (Niklas
Schnelle)
- Align s390 with AER and EEH by emitting uevents during error
recovery (Niklas Schnelle)
- Align EEH with AER and s390 by emitting BEGIN_RECOVERY,
SUCCESSFUL_RECOVERY, or FAILED_RECOVERY uevents depending on the
result of err_handler.error_detected() (Niklas Schnelle)
- Fix a NULL pointer dereference in aer_ratelimit() when ACPI GHES
error information identifies a device without an AER Capability
(Breno Leitao)
- Update error decoding and TLP Log printing for new errors in
current PCIe base spec (Lukas Wunner)
- Update error recovery documentation to match the current code
and use consistent nomenclature (Lukas Wunner)
ASPM:
- Enable all ClockPM and ASPM states for devicetree platforms, since
there's typically no firmware that enables ASPM
This is a risky change that may uncover hardware or configuration
defects at boot-time rather than when users enable ASPM via sysfs
later. Booting with "pcie_aspm=off" prevents this enabling
(Manivannan Sadhasivam)
- Remove the qcom code that enabled ASPM (Manivannan Sadhasivam)
Power management:
- If a device has already been disconnected, e.g., by a hotplug
removal, don't bother trying to resume it to D0 when detaching the
driver.
This avoids annoying "Unable to change power state from D3cold to
D0" messages (Mario Limonciello)
- Ensure devices are powered up before config reads for
'max_link_width', 'current_link_speed', 'current_link_width',
'secondary_bus_number', and 'subordinate_bus_number' sysfs files.
This prevents using invalid data (~0) in drivers or lspci and,
depending on how the PCIe controller reports errors, may avoid
error interrupts or crashes (Brian Norris)
Virtualization:
- Add rescan/remove locking when enabling/disabling SR-IOV, which
avoids list corruption on s390, where disabling SR-IOV also
generates hotplug events (Niklas Schnelle)
Peer-to-peer DMA:
- Free struct p2p_pgmap, not a member within it, in the
pci_p2pdma_add_resource() error path (Sungho Kim)
Endpoint framework:
- Document sysfs interface for BAR assignment of vNTB endpoint
functions (Jerome Brunet)
- Fix array underflow in endpoint BAR test case (Dan Carpenter)
- Skip endpoint IRQ test if the IRQ is out of range to avoid false
errors (Christian Bruel)
- Fix endpoint test case for controllers with fixed-size BARs smaller
than requested by the test (Marek Vasut)
- Restore inbound translation when disabling doorbell so the endpoint
doorbell test case can be run more than once (Niklas Cassel)
- Avoid a NULL pointer dereference when releasing DMA channels in
endpoint DMA test case (Shin'ichiro Kawasaki)
- Convert tegra194 interrupt number to MSI vector to fix endpoint
Kselftest MSI_TEST test case (Niklas Cassel)
- Reset tegra194 BARs when running in endpoint mode so the BAR tests
don't overwrite the ATU settings in BAR4 (Niklas Cassel)
- Handle errors in tegra194 BPMP transactions so we don't mistakenly
skip future PERST# assertion (Vidya Sagar)
AMD MDB PCIe controller driver:
- Update DT binding example to separate PERST# to a Root Port stanza
to make multiple Root Ports possible in the future (Sai Krishna
Musham)
- Add driver support for PERST# being described in a Root Port
stanza, falling back to the host bridge if not found there (Sai
Krishna Musham)
Freescale i.MX6 PCIe controller driver:
- Enable the 3.3V Vaux supply if available so devices can request
wakeup with either Beacon or WAKE# (Richard Zhu)
MediaTek PCIe Gen3 controller driver:
- Add optional sys clock ready time setting to avoid sys_clk_rdy
signal glitching in MT6991 and MT8196 (AngeloGioacchino Del Regno)
- Add DT binding and driver support for MT6991 and MT8196
(AngeloGioacchino Del Regno)
NVIDIA Tegra PCIe controller driver:
- When asserting PERST#, disable the controller instead of mistakenly
disabling the PLL twice (Nagarjuna Kristam)
- Convert struct tegra_msi mask_lock to raw spinlock to avoid a lock
nesting error (Marek Vasut)
Qualcomm PCIe controller driver:
- Select PCI Power Control Slot driver so slot voltage rails can be
turned on/off if described in Root Port devicetree node (Qiang Yu)
- Parse only PCI bridge child nodes in devicetree, skipping unrelated
nodes such as OPP (Operating Performance Points), which caused
probe failures (Krishna Chaitanya Chundru)
- Add 8.0 GT/s and 32.0 GT/s equalization settings (Ziyue Zhang)
- Consolidate Root Port 'phy' and 'reset' properties in struct
qcom_pcie_port, regardless of whether we got them from the Root
Port node or the host bridge node (Manivannan Sadhasivam)
- Fetch and map the ELBI register space in the DWC core rather than
in each driver individually (Krishna Chaitanya Chundru)
- Enable ECAM mechanism in DWC core by setting up iATU with 'CFG
Shift Feature' and use this in the qcom driver (Krishna Chaitanya
Chundru)
- Add SM8750 compatible to qcom,pcie-sm8550.yaml (Krishna Chaitanya
Chundru)
- Update qcom,pcie-x1e80100.yaml to allow fifth PCIe host on Qualcomm
Glymur, which is compatible with X1E80100 but doesn't have the
cnoc_sf_axi clock (Qiang Yu)
Renesas R-Car PCIe controller driver:
- Fix a typo that prevented correct PHY initialization (Marek Vasut)
- Add a missing 1ms delay after PWR reset assertion as required by
the V4H manual (Marek Vasut)
- Assure reset has completed before DBI access to avoid SError (Marek
Vasut)
- Fix inverted PHY initialization check, which sometimes led to
timeouts and failure to start the controller (Marek Vasut)
- Pass the correct IRQ domain to generic_handle_domain_irq() to fix a
regression when converting to msi_create_parent_irq_domain()
(Claudiu Beznea)
- Drop the spinlock protecting the PMSR register - it's no longer
required since pci_lock already serializes accesses (Marek Vasut)
- Convert struct rcar_msi mask_lock to raw spinlock to avoid a lock
nesting error (Marek Vasut)
SOPHGO PCIe controller driver:
- Check for existence of struct cdns_pcie.ops before using it to
allow Cadence drivers that don't need to supply ops (Chen Wang)
- Add DT binding and driver for the SOPHGO SG2042 PCIe controller
(Chen Wang)
STMicroelectronics STM32MP25 PCIe controller driver:
- Update pinctrl documentation of initial states and use in runtime
suspend/resume (Christian Bruel)
- Add pinctrl_pm_select_init_state() for use by stm32 driver, which
needs it during resume (Christian Bruel)
- Add devicetree bindings and drivers for the STMicroelectronics
STM32MP25 in host and endpoint modes (Christian Bruel)
Synopsys DesignWare PCIe controller driver:
- Add support for x16 in devicetree 'num-lanes' property (Konrad
Dybcio)
- Verify that if DT specifies a single IRQ for all eDMA channels, it
is named 'dma' (Niklas Cassel)
TI J721E PCIe driver:
- Add MODULE_DEVICE_TABLE() so driver can be autoloaded (Siddharth
Vadapalli)
- Power controller off before configuring the glue layer so the
controller latches the correct values on power-on (Siddharth
Vadapalli)
TI Keystone PCIe controller driver:
- Use devm_request_irq() so 'ks-pcie-error-irq' is freed when driver
exits with error (Siddharth Vadapalli)
- Add Peripheral Virtualization Unit (PVU), which restricts DMA from
PCIe devices to specific regions of host memory, to the ti,am65
binding (Jan Kiszka)
Xilinx NWL PCIe controller driver:
- Clear bootloader E_ECAM_CONTROL before merging in the new driver
value to avoid writing invalid values (Jani Nurminen)"
* tag 'pci-v6.18-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/pci/pci: (141 commits)
PCI/AER: Avoid NULL pointer dereference in aer_ratelimit()
MAINTAINERS: Add entry for ST STM32MP25 PCIe drivers
PCI: stm32-ep: Add PCIe Endpoint support for STM32MP25
dt-bindings: PCI: Add STM32MP25 PCIe Endpoint bindings
PCI: stm32: Add PCIe host support for STM32MP25
PCI: xilinx-nwl: Fix ECAM programming
PCI: j721e: Fix incorrect error message in probe()
PCI: keystone: Use devm_request_irq() to free "ks-pcie-error-irq" on exit
dt-bindings: PCI: qcom,pcie-x1e80100: Set clocks minItems for the fifth Glymur PCIe Controller
PCI: dwc: Support 16-lane operation
PCI: Add lockdep assertion in pci_stop_and_remove_bus_device()
PCI/IOV: Add PCI rescan-remove locking when enabling/disabling SR-IOV
PCI: rcar-host: Convert struct rcar_msi mask_lock into raw spinlock
PCI: tegra194: Rename 'root_bus' to 'root_port_bus' in tegra_pcie_downstream_dev_to_D0()
PCI: tegra: Convert struct tegra_msi mask_lock into raw spinlock
PCI: rcar-gen4: Fix inverted break condition in PHY initialization
PCI: rcar-gen4: Assure reset occurs before DBI access
PCI: rcar-gen4: Add missing 1ms delay after PWR reset assertion
PCI: Set up bridge resources earlier
PCI: rcar-host: Drop PMSR spinlock
...
|
||
|
Linus Torvalds
|
7c738cb4ca |
Merge tag 'x86_entry_for_6.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 entry updates from Dave Hansen: "A pair of x86/entry updates. The FRED one adjusts the kernel to the latest spec. The spec change prevents attackers from abusing kernel entry points. The second one came about because of the LASS work[1]. It moves the vsyscall emulation code away from depending on X86_PF_INSTR which is not available on some CPUs. Those CPUs are pretty obscure these days, but this still seems like the right thing to do. It also makes this code consistent with some things that the LASS code is going to do. - Use RIP instead of X86_PF_INSTR for vsyscall emulation - Remove ENDBR64 from FRED entry points" Link: https://lore.kernel.org/lkml/20250620135325.3300848-1-kirill.shutemov@linux.intel.com/ [1] * tag 'x86_entry_for_6.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/fred: Remove ENDBR64 from FRED entry points x86/vsyscall: Do not require X86_PF_INSTR to emulate vsyscall |
||
|
Linus Torvalds
|
be786eba12 |
Merge tag 'x86_mm_for_6.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 mm update from Dave Hansen: "A single change to remove an open-coded TLB flush operation by using an existing helper. This came out of Rik van Riel's work to get the INVLPGB instruction working. - Change cpa_flush() to call flush_kernel_range() directly" * tag 'x86_mm_for_6.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/mm: Change cpa_flush() to call flush_kernel_range() directly |
||
|
Linus Torvalds
|
50ac57c3b1 |
Merge tag 'x86_tdx_for_6.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 TDX updates from Dave Hansen:
"The biggest change here is making TDX and kexec play nicely together.
Before this, the memory encryption hardware (which doesn't respect
cache coherency) could write back old cachelines on top of data in the
new kernel, so kexec and TDX were made mutually exclusive. This
removes the limitation.
There is also some work to tighten up a hardware bug workaround and
some MAINTAINERS updates.
- Make TDX and kexec work together
- Skip TDX bug workaround when the bug is not present
- Update maintainers entries"
* tag 'x86_tdx_for_6.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/virt/tdx: Use precalculated TDVPR page physical address
KVM/TDX: Explicitly do WBINVD when no more TDX SEAMCALLs
x86/virt/tdx: Update the kexec section in the TDX documentation
x86/virt/tdx: Remove the !KEXEC_CORE dependency
x86/kexec: Disable kexec/kdump on platforms with TDX partial write erratum
x86/virt/tdx: Mark memory cache state incoherent when making SEAMCALL
x86/sme: Use percpu boolean to control WBINVD during kexec
x86/kexec: Consolidate relocate_kernel() function parameters
x86/tdx: Skip clearing reclaimed pages unless X86_BUG_TDX_PW_MCE is present
x86/tdx: Tidy reset_pamt functions
x86/tdx: Eliminate duplicate code in tdx_clear_page()
MAINTAINERS: Add KVM mail list to the TDX entry
MAINTAINERS: Add Rick Edgecombe as a TDX reviewer
MAINTAINERS: Update the file list in the TDX entry.
|
||
|
Linus Torvalds
|
f3826aa996 |
Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull kvm updates from Paolo Bonzini:
"This excludes the bulk of the x86 changes, which I will send
separately. They have two not complex but relatively unusual conflicts
so I will wait for other dust to settle.
guest_memfd:
- Add support for host userspace mapping of guest_memfd-backed memory
for VM types that do NOT use support KVM_MEMORY_ATTRIBUTE_PRIVATE
(which isn't precisely the same thing as CoCo VMs, since x86's
SEV-MEM and SEV-ES have no way to detect private vs. shared).
This lays the groundwork for removal of guest memory from the
kernel direct map, as well as for limited mmap() for
guest_memfd-backed memory.
For more information see:
- commit
|
||
|
Linus Torvalds
|
e406d57be7 |
Merge tag 'mm-nonmm-stable-2025-10-02-15-29' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull non-MM updates from Andrew Morton: - "ida: Remove the ida_simple_xxx() API" from Christophe Jaillet completes the removal of this legacy IDR API - "panic: introduce panic status function family" from Jinchao Wang provides a number of cleanups to the panic code and its various helpers, which were rather ad-hoc and scattered all over the place - "tools/delaytop: implement real-time keyboard interaction support" from Fan Yu adds a few nice user-facing usability changes to the delaytop monitoring tool - "efi: Fix EFI boot with kexec handover (KHO)" from Evangelos Petrongonas fixes a panic which was happening with the combination of EFI and KHO - "Squashfs: performance improvement and a sanity check" from Phillip Lougher teaches squashfs's lseek() about SEEK_DATA/SEEK_HOLE. A mere 150x speedup was measured for a well-chosen microbenchmark - plus another 50-odd singleton patches all over the place * tag 'mm-nonmm-stable-2025-10-02-15-29' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (75 commits) Squashfs: reject negative file sizes in squashfs_read_inode() kallsyms: use kmalloc_array() instead of kmalloc() MAINTAINERS: update Sibi Sankar's email address Squashfs: add SEEK_DATA/SEEK_HOLE support Squashfs: add additional inode sanity checking lib/genalloc: fix device leak in of_gen_pool_get() panic: remove CONFIG_PANIC_ON_OOPS_VALUE ocfs2: fix double free in user_cluster_connect() checkpatch: suppress strscpy warnings for userspace tools cramfs: fix incorrect physical page address calculation kernel: prevent prctl(PR_SET_PDEATHSIG) from racing with parent process exit Squashfs: fix uninit-value in squashfs_get_parent kho: only fill kimage if KHO is finalized ocfs2: avoid extra calls to strlen() after ocfs2_sprintf_system_inode_name() kernel/sys.c: fix the racy usage of task_lock(tsk->group_leader) in sys_prlimit64() paths sched/task.h: fix the wrong comment on task_lock() nesting with tasklist_lock coccinelle: platform_no_drv_owner: handle also built-in drivers coccinelle: of_table: handle SPI device ID tables lib/decompress: use designated initializers for struct compress_format efi: support booting with kexec handover (KHO) ... |
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Linus Torvalds
|
8804d970fa |
Merge tag 'mm-stable-2025-10-01-19-00' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull MM updates from Andrew Morton:
- "mm, swap: improve cluster scan strategy" from Kairui Song improves
performance and reduces the failure rate of swap cluster allocation
- "support large align and nid in Rust allocators" from Vitaly Wool
permits Rust allocators to set NUMA node and large alignment when
perforning slub and vmalloc reallocs
- "mm/damon/vaddr: support stat-purpose DAMOS" from Yueyang Pan extend
DAMOS_STAT's handling of the DAMON operations sets for virtual
address spaces for ops-level DAMOS filters
- "execute PROCMAP_QUERY ioctl under per-vma lock" from Suren
Baghdasaryan reduces mmap_lock contention during reads of
/proc/pid/maps
- "mm/mincore: minor clean up for swap cache checking" from Kairui Song
performs some cleanup in the swap code
- "mm: vm_normal_page*() improvements" from David Hildenbrand provides
code cleanup in the pagemap code
- "add persistent huge zero folio support" from Pankaj Raghav provides
a block layer speedup by optionalls making the
huge_zero_pagepersistent, instead of releasing it when its refcount
falls to zero
- "kho: fixes and cleanups" from Mike Rapoport adds a few touchups to
the recently added Kexec Handover feature
- "mm: make mm->flags a bitmap and 64-bit on all arches" from Lorenzo
Stoakes turns mm_struct.flags into a bitmap. To end the constant
struggle with space shortage on 32-bit conflicting with 64-bit's
needs
- "mm/swapfile.c and swap.h cleanup" from Chris Li cleans up some swap
code
- "selftests/mm: Fix false positives and skip unsupported tests" from
Donet Tom fixes a few things in our selftests code
- "prctl: extend PR_SET_THP_DISABLE to only provide THPs when advised"
from David Hildenbrand "allows individual processes to opt-out of
THP=always into THP=madvise, without affecting other workloads on the
system".
It's a long story - the [1/N] changelog spells out the considerations
- "Add and use memdesc_flags_t" from Matthew Wilcox gets us started on
the memdesc project. Please see
https://kernelnewbies.org/MatthewWilcox/Memdescs and
https://blogs.oracle.com/linux/post/introducing-memdesc
- "Tiny optimization for large read operations" from Chi Zhiling
improves the efficiency of the pagecache read path
- "Better split_huge_page_test result check" from Zi Yan improves our
folio splitting selftest code
- "test that rmap behaves as expected" from Wei Yang adds some rmap
selftests
- "remove write_cache_pages()" from Christoph Hellwig removes that
function and converts its two remaining callers
- "selftests/mm: uffd-stress fixes" from Dev Jain fixes some UFFD
selftests issues
- "introduce kernel file mapped folios" from Boris Burkov introduces
the concept of "kernel file pages". Using these permits btrfs to
account its metadata pages to the root cgroup, rather than to the
cgroups of random inappropriate tasks
- "mm/pageblock: improve readability of some pageblock handling" from
Wei Yang provides some readability improvements to the page allocator
code
- "mm/damon: support ARM32 with LPAE" from SeongJae Park teaches DAMON
to understand arm32 highmem
- "tools: testing: Use existing atomic.h for vma/maple tests" from
Brendan Jackman performs some code cleanups and deduplication under
tools/testing/
- "maple_tree: Fix testing for 32bit compiles" from Liam Howlett fixes
a couple of 32-bit issues in tools/testing/radix-tree.c
- "kasan: unify kasan_enabled() and remove arch-specific
implementations" from Sabyrzhan Tasbolatov moves KASAN arch-specific
initialization code into a common arch-neutral implementation
- "mm: remove zpool" from Johannes Weiner removes zspool - an
indirection layer which now only redirects to a single thing
(zsmalloc)
- "mm: task_stack: Stack handling cleanups" from Pasha Tatashin makes a
couple of cleanups in the fork code
- "mm: remove nth_page()" from David Hildenbrand makes rather a lot of
adjustments at various nth_page() callsites, eventually permitting
the removal of that undesirable helper function
- "introduce kasan.write_only option in hw-tags" from Yeoreum Yun
creates a KASAN read-only mode for ARM, using that architecture's
memory tagging feature. It is felt that a read-only mode KASAN is
suitable for use in production systems rather than debug-only
- "mm: hugetlb: cleanup hugetlb folio allocation" from Kefeng Wang does
some tidying in the hugetlb folio allocation code
- "mm: establish const-correctness for pointer parameters" from Max
Kellermann makes quite a number of the MM API functions more accurate
about the constness of their arguments. This was getting in the way
of subsystems (in this case CEPH) when they attempt to improving
their own const/non-const accuracy
- "Cleanup free_pages() misuse" from Vishal Moola fixes a number of
code sites which were confused over when to use free_pages() vs
__free_pages()
- "Add Rust abstraction for Maple Trees" from Alice Ryhl makes the
mapletree code accessible to Rust. Required by nouveau and by its
forthcoming successor: the new Rust Nova driver
- "selftests/mm: split_huge_page_test: split_pte_mapped_thp
improvements" from David Hildenbrand adds a fix and some cleanups to
the thp selftesting code
- "mm, swap: introduce swap table as swap cache (phase I)" from Chris
Li and Kairui Song is the first step along the path to implementing
"swap tables" - a new approach to swap allocation and state tracking
which is expected to yield speed and space improvements. This
patchset itself yields a 5-20% performance benefit in some situations
- "Some ptdesc cleanups" from Matthew Wilcox utilizes the new memdesc
layer to clean up the ptdesc code a little
- "Fix va_high_addr_switch.sh test failure" from Chunyu Hu fixes some
issues in our 5-level pagetable selftesting code
- "Minor fixes for memory allocation profiling" from Suren Baghdasaryan
addresses a couple of minor issues in relatively new memory
allocation profiling feature
- "Small cleanups" from Matthew Wilcox has a few cleanups in
preparation for more memdesc work
- "mm/damon: add addr_unit for DAMON_LRU_SORT and DAMON_RECLAIM" from
Quanmin Yan makes some changes to DAMON in furtherance of supporting
arm highmem
- "selftests/mm: Add -Wunreachable-code and fix warnings" from Muhammad
Anjum adds that compiler check to selftests code and fixes the
fallout, by removing dead code
- "Improvements to Victim Process Thawing and OOM Reaper Traversal
Order" from zhongjinji makes a number of improvements in the OOM
killer: mainly thawing a more appropriate group of victim threads so
they can release resources
- "mm/damon: misc fixups and improvements for 6.18" from SeongJae Park
is a bunch of small and unrelated fixups for DAMON
- "mm/damon: define and use DAMON initialization check function" from
SeongJae Park implement reliability and maintainability improvements
to a recently-added bug fix
- "mm/damon/stat: expose auto-tuned intervals and non-idle ages" from
SeongJae Park provides additional transparency to userspace clients
of the DAMON_STAT information
- "Expand scope of khugepaged anonymous collapse" from Dev Jain removes
some constraints on khubepaged's collapsing of anon VMAs. It also
increases the success rate of MADV_COLLAPSE against an anon vma
- "mm: do not assume file == vma->vm_file in compat_vma_mmap_prepare()"
from Lorenzo Stoakes moves us further towards removal of
file_operations.mmap(). This patchset concentrates upon clearing up
the treatment of stacked filesystems
- "mm: Improve mlock tracking for large folios" from Kiryl Shutsemau
provides some fixes and improvements to mlock's tracking of large
folios. /proc/meminfo's "Mlocked" field became more accurate
- "mm/ksm: Fix incorrect accounting of KSM counters during fork" from
Donet Tom fixes several user-visible KSM stats inaccuracies across
forks and adds selftest code to verify these counters
- "mm_slot: fix the usage of mm_slot_entry" from Wei Yang addresses
some potential but presently benign issues in KSM's mm_slot handling
* tag 'mm-stable-2025-10-01-19-00' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (372 commits)
mm: swap: check for stable address space before operating on the VMA
mm: convert folio_page() back to a macro
mm/khugepaged: use start_addr/addr for improved readability
hugetlbfs: skip VMAs without shareable locks in hugetlb_vmdelete_list
alloc_tag: fix boot failure due to NULL pointer dereference
mm: silence data-race in update_hiwater_rss
mm/memory-failure: don't select MEMORY_ISOLATION
mm/khugepaged: remove definition of struct khugepaged_mm_slot
mm/ksm: get mm_slot by mm_slot_entry() when slot is !NULL
hugetlb: increase number of reserving hugepages via cmdline
selftests/mm: add fork inheritance test for ksm_merging_pages counter
mm/ksm: fix incorrect KSM counter handling in mm_struct during fork
drivers/base/node: fix double free in register_one_node()
mm: remove PMD alignment constraint in execmem_vmalloc()
mm/memory_hotplug: fix typo 'esecially' -> 'especially'
mm/rmap: improve mlock tracking for large folios
mm/filemap: map entire large folio faultaround
mm/fault: try to map the entire file folio in finish_fault()
mm/rmap: mlock large folios in try_to_unmap_one()
mm/rmap: fix a mlock race condition in folio_referenced_one()
...
|
||
|
Linus Torvalds
|
58809f614e |
Merge tag 'drm-next-2025-10-01' of https://gitlab.freedesktop.org/drm/kernel
Pull drm updates from Dave Airlie:
"cross-subsystem:
- i2c-hid: Make elan touch controllers power on after panel is
enabled
- dt bindings for STM32MP25 SoC
- pci vgaarb: use screen_info helpers
- rust pin-init updates
- add MEI driver for late binding firmware update/load
uapi:
- add ioctl for reassigning GEM handles
- provide boot_display attribute on boot-up devices
core:
- document DRM_MODE_PAGE_FLIP_EVENT
- add vendor specific recovery method to drm device wedged uevent
gem:
- Simplify gpuvm locking
ttm:
- add interface to populate buffers
sched:
- Fix race condition in trace code
atomic:
- Reallow no-op async page flips
display:
- dp: Fix command length
video:
- Improve pixel-format handling for struct screen_info
rust:
- drop Opaque<> from ioctl args
- Alloc:
- BorrowedPage type and AsPageIter traits
- Implement Vmalloc::to_page() and VmallocPageIter
- DMA/Scatterlist:
- Add dma::DataDirection and type alias for dma_addr_t
- Abstraction for struct scatterlist and sg_table
- DRM:
- simplify use of generics
- add DriverFile type alias
- drop Object::SIZE
- Rust:
- pin-init tree merge
- Various methods for AsBytes and FromBytes traits
gpuvm:
- Support madvice in Xe driver
gpusvm:
- fix hmm_pfn_to_map_order usage in gpusvm
bridge:
- Improve and fix ref counting on bridge management
- cdns-dsi: Various improvements to mode setting
- Support Solomon SSD2825 plus DT bindings
- Support Waveshare DSI2DPI plus DT bindings
- Support Content Protection property
- display-connector: Improve DP display detection
- Add support for Radxa Ra620 plus DT bindings
- adv7511: Provide SPD and HDMI infoframes
- it6505: Replace crypto_shash with sha()
- synopsys: Add support for DW DPTX Controller plus DT bindings
- adv7511: Write full Audio infoframe
- ite6263: Support vendor-specific infoframes
- simple: Add support for Realtek RTD2171 DP-to-HDMI plus DT bindings
panel:
- panel-edp: Support mt8189 Chromebooks; Support BOE NV140WUM-N64;
Support SHP LQ134Z1; Fixes
- panel-simple: Support Olimex LCD-OLinuXino-5CTS plus DT bindings
- Support Samsung AMS561RA01
- Support Hydis HV101HD1 plus DT bindings
- ilitek-ili9881c: Refactor mode setting; Add support for Bestar
BSD1218-A101KL68 LCD plus DT bindings
- lvds: Add support for Ampire AMP19201200B5TZQW-T03 to DT bindings
- edp: Add support for additonal mt8189 Chromebook panels
- lvds: Add DT bindings for EDT ETML0700Z8DHA
amdgpu:
- add CRIU support for gem objects
- RAS updates
- VCN SRAM load fixes
- EDID read fixes
- eDP ALPM support
- Documentation updates
- Rework PTE flag generation
- DCE6 fixes
- VCN devcoredump cleanup
- MMHUB client id fixes
- VCN 5.0.1 RAS support
- SMU 13.0.x updates
- Expanded PCIe DPC support
- Expanded VCN reset support
- VPE per queue reset support
- give kernel jobs unique id for tracing
- pre-populate exported buffers
- cyan skillfish updates
- make vbios build number available in sysfs
- userq updates
- HDCP updates
- support MMIO remap page as ttm pool
- JPEG parser updates
- DCE6 DC updates
- use devm for i2c buses
- GPUVM locking updates
- Drop non-DC DCE11 code
- improve fallback handling for pixel encoding
amdkfd:
- SVM/page migration fixes
- debugfs fixes
- add CRIO support for gem objects
- SVM updates
radeon:
- use dev_warn_once in CS parsers
xe:
- add madvise interface
- add DRM_IOCTL_XE_VM_QUERY_MEMORY_RANGE_ATTRS to query VMA count
and memory attributes
- drop L# bank mask reporting from media GT3 on Xe3+.
- add SLPC power_profile sysfs interface
- add configs attribs to add post/mid context-switch commands
- handle firmware reported hardware errors notifying userspace with
device wedged uevent
- use same dir structure across sysfs/debugfs
- cleanup and future proof vram region init
- add G-states and PCI link states to debugfs
- Add SRIOV support for CCS surfaces on Xe2+
- Enable SRIOV PF mode by default on supported platforms
- move flush to common code
- extended core workarounds for Xe2/3
- use DRM scheduler for delayed GT TLB invalidations
- configs improvements and allow VF device enablement
- prep work to expose mmio regions to userspace
- VF migration support added
- prepare GPU SVM for THP migration
- start fixing XE_PAGE_SIZE vs PAGE_SIZE
- add PSMI support for hw validation
- resize VF bars to max possible size according to number of VFs
- Ensure GT is in C0 during resume
- pre-populate exported buffers
- replace xe_hmm with gpusvm
- add more SVM GT stats to debugfs
- improve fake pci and WA kunnit handle for new platform testing
- Test GuC to GuC comms to add debugging
- use attribute groups to simplify sysfs registration
- add Late Binding firmware code to interact with MEI
i915:
- apply multiple JSL/EHL/Gen7/Gen6 workarounds properly
- protect against overflow in active_engine()
- Use try_cmpxchg64() in __active_lookup()
- include GuC registers in error state
- get rid of dev->struct_mutex
- iopoll: generalize read_poll_timout
- lots more display refactoring
- Reject HBR3 in any eDP Panel
- Prune modes for YUV420
- Display Wa fix, additions, and updates
- DP: Fix 2.7 Gbps link training on g4x
- DP: Adjust the idle pattern handling
- DP: Shuffle the link training code a bit
- Don't set/read the DSI C clock divider on GLK
- Enable_psr kernel parameter changes
- Type-C enabled/disconnected dp-alt sink
- Wildcat Lake enabling
- DP HDR updates
- DRAM detection
- wait PSR idle on dsb commit
- Remove FBC modulo 4 restriction for ADL-P+
- panic: refactor framebuffer allocation
habanalabs:
- debug/visibility improvements
- vmalloc-backed coherent mmap support
- HLDIO infrastructure
nova-core:
- various register!() macro improvements
- minor vbios/firmware fixes/refactoring
- advance firmware boot stages; process Booter and patch signatures
- process GSP and GSP bootloader
- Add r570.144 firmware bindings and update to it
- Move GSP boot code to own module
- Use new pin-init features to store driver's private data in a
single allocation
- Update ARef import from sync::aref
nova-drm:
- Update ARef import from sync::aref
tyr:
- initial driver skeleton for a rust driver for ARM Mali GPUs
- capable of powering up, query metadata and provide it to userspace.
msm:
- GPU and Core:
- in DT bindings describe clocks per GPU type
- GMU bandwidth voting for x1-85
- a623/a663 speedbins
- cleanup some remaining no-iommu leftovers after VM_BIND conversion
- fix GEM obj 32b size truncation
- add missing VM_BIND param validation
- IFPC for x1-85 and a750
- register xml and gen_header.py sync from mesa
- Display:
- add missing bindings for display on SC8180X
- added DisplayPort MST bindings
- conversion from round_rate() to determine_rate()
amdxdna:
- add IOCTL_AMDXDNA_GET_ARRAY
- support user space allocated buffers
- streamline PM interfaces
- Refactoring wrt. hardware contexts
- improve error reporting
nouveau:
- use GSP firmware by default
- improve error reporting
- Pre-populate exported buffers
ast:
- Clean up detection of DRAM config
exynos:
- add DSIM bridge driver support for Exynos7870
- Document Exynos7870 DSIM compatible in dt-binding
panthor:
- Print task/pid on errors
- Add support for Mali G710, G510, G310, Gx15, Gx20, Gx25
- Improve cache flushing
- Fail VM bind if BO has offset
renesas:
- convert to RUNTIME_PM_OPS
rcar-du:
- Make number of lanes configurable
- Use RUNTIME_PM_OPS
- Add support for DSI commands
rocket:
- Add driver for Rockchip NPU plus DT bindings
- Use kfree() and sizeof() correctly
- Test DMA status
rockchip:
- dsi2: Add support for RK3576 plus DT bindings
- Add support for RK3588 DPTX output
tidss:
- Use crtc_ fields for programming display mode
- Remove other drivers from aperture
pixpaper:
- Add support for Mayqueen Pixpaper plus DT bindings
v3d:
- Support querying nubmer of GPU resets for KHR_robustness
stm:
- Clean up logging
- ltdc: Add support support for STM32MP257F-EV1 plus DT bindings
sitronix:
- st7571-i2c: Add support for inverted displays and 2-bit grayscale
tidss:
- Convert to kernel's FIELD_ macros
vesadrm:
- Support 8-bit palette mode
imagination:
- Improve power management
- Add support for TH1520 GPU
- Support Risc-V architectures
v3d:
- Improve job management and locking
vkms:
- Support variants of ARGB8888, ARGB16161616, RGB565, RGB888 and P01x
- Spport YUV with 16-bit components"
* tag 'drm-next-2025-10-01' of https://gitlab.freedesktop.org/drm/kernel: (1455 commits)
drm/amd: Add name to modes from amdgpu_connector_add_common_modes()
drm/amd: Drop some common modes from amdgpu_connector_add_common_modes()
drm/amdgpu: update MODULE_PARM_DESC for freesync_video
drm/amd: Use dynamic array size declaration for amdgpu_connector_add_common_modes()
drm/amd/display: Share dce100_validate_global with DCE6-8
drm/amd/display: Share dce100_validate_bandwidth with DCE6-8
drm/amdgpu: Fix fence signaling race condition in userqueue
amd/amdkfd: enhance kfd process check in switch partition
amd/amdkfd: resolve a race in amdgpu_amdkfd_device_fini_sw
drm/amd/display: Reject modes with too high pixel clock on DCE6-10
drm/amd: Drop unnecessary check in amdgpu_connector_add_common_modes()
drm/amd/display: Only enable common modes for eDP and LVDS
drm/amdgpu: remove the redeclaration of variable i
drm/amdgpu/userq: assign an error code for invalid userq va
drm/amdgpu: revert "rework reserved VMID handling" v2
drm/amdgpu: remove leftover from enforcing isolation by VMID
drm/amdgpu: Add fallback to pipe reset if KCQ ring reset fails
accel/habanalabs: add Infineon version check
accel/habanalabs/gaudi2: read preboot status after recovering from dirty state
accel/habanalabs: add HL_GET_P_STATE passthrough type
...
|
||
|
Linus Torvalds
|
e1b1d03cee |
Merge tag 'for-6.18/block-20250929' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux
Pull block updates from Jens Axboe:
- NVMe pull request via Keith:
- FC target fixes (Daniel)
- Authentication fixes and updates (Martin, Chris)
- Admin controller handling (Kamaljit)
- Target lockdep assertions (Max)
- Keep-alive updates for discovery (Alastair)
- Suspend quirk (Georg)
- MD pull request via Yu:
- Add support for a lockless bitmap.
A key feature for the new bitmap are that the IO fastpath is
lockless. If a user issues lots of write IO to the same bitmap
bit in a short time, only the first write has additional overhead
to update bitmap bit, no additional overhead for the following
writes.
By supporting only resync or recover written data, means in the
case creating new array or replacing with a new disk, there is no
need to do a full disk resync/recovery.
- Switch ->getgeo() and ->bios_param() to using struct gendisk rather
than struct block_device.
- Rust block changes via Andreas. This series adds configuration via
configfs and remote completion to the rnull driver. The series also
includes a set of changes to the rust block device driver API: a few
cleanup patches, and a few features supporting the rnull changes.
The series removes the raw buffer formatting logic from
`kernel::block` and improves the logic available in `kernel::string`
to support the same use as the removed logic.
- floppy arch cleanups
- Reduce the number of dereferencing needed for ublk commands
- Restrict supported sockets for nbd. Mostly done to eliminate a class
of issues perpetually reported by syzbot, by using nonsensical socket
setups.
- A few s390 dasd block fixes
- Fix a few issues around atomic writes
- Improve DMA interation for integrity requests
- Improve how iovecs are treated with regards to O_DIRECT aligment
constraints.
We used to require each segment to adhere to the constraints, now
only the request as a whole needs to.
- Clean up and improve p2p support, enabling use of p2p for metadata
payloads
- Improve locking of request lookup, using SRCU where appropriate
- Use page references properly for brd, avoiding very long RCU sections
- Fix ordering of recursively submitted IOs
- Clean up and improve updating nr_requests for a live device
- Various fixes and cleanups
* tag 'for-6.18/block-20250929' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux: (164 commits)
s390/dasd: enforce dma_alignment to ensure proper buffer validation
s390/dasd: Return BLK_STS_INVAL for EINVAL from do_dasd_request
ublk: remove redundant zone op check in ublk_setup_iod()
nvme: Use non zero KATO for persistent discovery connections
nvmet: add safety check for subsys lock
nvme-core: use nvme_is_io_ctrl() for I/O controller check
nvme-core: do ioccsz/iorcsz validation only for I/O controllers
nvme-core: add method to check for an I/O controller
blk-cgroup: fix possible deadlock while configuring policy
blk-mq: fix null-ptr-deref in blk_mq_free_tags() from error path
blk-mq: Fix more tag iteration function documentation
selftests: ublk: fix behavior when fio is not installed
ublk: don't access ublk_queue in ublk_unmap_io()
ublk: pass ublk_io to __ublk_complete_rq()
ublk: don't access ublk_queue in ublk_need_complete_req()
ublk: don't access ublk_queue in ublk_check_commit_and_fetch()
ublk: don't pass ublk_queue to ublk_fetch()
ublk: don't access ublk_queue in ublk_config_io_buf()
ublk: don't access ublk_queue in ublk_check_fetch_buf()
ublk: pass q_id and tag to __ublk_check_and_get_req()
...
|
||
|
Linus Torvalds
|
ae28ed4578 |
Merge tag 'bpf-next-6.18' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Pull bpf updates from Alexei Starovoitov: - Support pulling non-linear xdp data with bpf_xdp_pull_data() kfunc (Amery Hung) Applied as a stable branch in bpf-next and net-next trees. - Support reading skb metadata via bpf_dynptr (Jakub Sitnicki) Also a stable branch in bpf-next and net-next trees. - Enforce expected_attach_type for tailcall compatibility (Daniel Borkmann) - Replace path-sensitive with path-insensitive live stack analysis in the verifier (Eduard Zingerman) This is a significant change in the verification logic. More details, motivation, long term plans are in the cover letter/merge commit. - Support signed BPF programs (KP Singh) This is another major feature that took years to materialize. Algorithm details are in the cover letter/marge commit - Add support for may_goto instruction to s390 JIT (Ilya Leoshkevich) - Add support for may_goto instruction to arm64 JIT (Puranjay Mohan) - Fix USDT SIB argument handling in libbpf (Jiawei Zhao) - Allow uprobe-bpf program to change context registers (Jiri Olsa) - Support signed loads from BPF arena (Kumar Kartikeya Dwivedi and Puranjay Mohan) - Allow access to union arguments in tracing programs (Leon Hwang) - Optimize rcu_read_lock() + migrate_disable() combination where it's used in BPF subsystem (Menglong Dong) - Introduce bpf_task_work_schedule*() kfuncs to schedule deferred execution of BPF callback in the context of a specific task using the kernel’s task_work infrastructure (Mykyta Yatsenko) - Enforce RCU protection for KF_RCU_PROTECTED kfuncs (Kumar Kartikeya Dwivedi) - Add stress test for rqspinlock in NMI (Kumar Kartikeya Dwivedi) - Improve the precision of tnum multiplier verifier operation (Nandakumar Edamana) - Use tnums to improve is_branch_taken() logic (Paul Chaignon) - Add support for atomic operations in arena in riscv JIT (Pu Lehui) - Report arena faults to BPF error stream (Puranjay Mohan) - Search for tracefs at /sys/kernel/tracing first in bpftool (Quentin Monnet) - Add bpf_strcasecmp() kfunc (Rong Tao) - Support lookup_and_delete_elem command in BPF_MAP_STACK_TRACE (Tao Chen) * tag 'bpf-next-6.18' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (197 commits) libbpf: Replace AF_ALG with open coded SHA-256 selftests/bpf: Add stress test for rqspinlock in NMI selftests/bpf: Add test case for different expected_attach_type bpf: Enforce expected_attach_type for tailcall compatibility bpftool: Remove duplicate string.h header bpf: Remove duplicate crypto/sha2.h header libbpf: Fix error when st-prefix_ops and ops from differ btf selftests/bpf: Test changing packet data from kfunc selftests/bpf: Add stacktrace map lookup_and_delete_elem test case selftests/bpf: Refactor stacktrace_map case with skeleton bpf: Add lookup_and_delete_elem for BPF_MAP_STACK_TRACE selftests/bpf: Fix flaky bpf_cookie selftest selftests/bpf: Test changing packet data from global functions with a kfunc bpf: Emit struct bpf_xdp_sock type in vmlinux BTF selftests/bpf: Task_work selftest cleanup fixes MAINTAINERS: Delete inactive maintainers from AF_XDP bpf: Mark kfuncs as __noclone selftests/bpf: Add kprobe multi write ctx attach test selftests/bpf: Add kprobe write ctx attach test selftests/bpf: Add uprobe context ip register change test ... |
||
|
Linus Torvalds
|
4b81e2eb9e |
Merge tag 'timers-vdso-2025-09-29' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull VDSO updates from Thomas Gleixner: - Further consolidation of the VDSO infrastructure and the common data store - Simplification of the related Kconfig logic - Improve the VDSO selftest suite * tag 'timers-vdso-2025-09-29' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: selftests: vDSO: Drop vdso_test_clock_getres selftests: vDSO: vdso_test_abi: Add tests for clock_gettime64() selftests: vDSO: vdso_test_abi: Test CPUTIME clocks selftests: vDSO: vdso_test_abi: Use explicit indices for name array selftests: vDSO: vdso_test_abi: Drop clock availability tests selftests: vDSO: vdso_test_abi: Use ksft_finished() selftests: vDSO: vdso_test_abi: Correctly skip whole test with missing vDSO selftests: vDSO: Fix -Wunitialized in powerpc VDSO_CALL() wrapper vdso: Add struct __kernel_old_timeval forward declaration to gettime.h vdso: Gate VDSO_GETRANDOM behind HAVE_GENERIC_VDSO vdso: Drop Kconfig GENERIC_VDSO_TIME_NS vdso: Drop Kconfig GENERIC_VDSO_DATA_STORE vdso: Drop kconfig GENERIC_COMPAT_VDSO vdso: Drop kconfig GENERIC_VDSO_32 riscv: vdso: Untangle Kconfig logic time: Build generic update_vsyscall() only with generic time vDSO vdso/gettimeofday: Remove !CONFIG_TIME_NS stubs vdso: Move ENABLE_COMPAT_VDSO from core to arm64 ARM: VDSO: Remove cntvct_ok global variable vdso/datastore: Gate time data behind CONFIG_GENERIC_GETTIMEOFDAY |
||
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Nam Cao
|
4691db0704 |
x86/hyperv: Switch to msi_create_parent_irq_domain()
Move away from the legacy MSI domain setup, switch to use msi_create_parent_irq_domain(). While doing the conversion, I noticed that hv_irq_compose_msi_msg() is doing more than it is supposed to (composing message content). The interrupt allocation bits should be moved into hv_msi_domain_alloc(). However, I have no hardware to test this change, therefore I leave a TODO note. Signed-off-by: Nam Cao <namcao@linutronix.de> Acked-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Nuno Das Neves <nunodasneves@linux.microsoft.com> Reviewed-by: Nuno Das Neves <nunodasneves@linux.microsoft.com> Signed-off-by: Wei Liu <wei.liu@kernel.org> |
||
|
Sean Christopherson
|
9be7e1e320 |
entry: Rename "kvm" entry code assets to "virt" to genericize APIs
Rename the "kvm" entry code files and Kconfigs to use generic "virt" nomenclature so that the code can be reused by other hypervisors (or rather, their root/dom0 partition drivers), without incorrectly suggesting the code somehow relies on and/or involves KVM. No functional change intended. Signed-off-by: Sean Christopherson <seanjc@google.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Joel Fernandes <joelagnelf@nvidia.com> Signed-off-by: Wei Liu <wei.liu@kernel.org> |
||
|
Sean Christopherson
|
6d0386ea99 |
entry/kvm: KVM: Move KVM details related to signal/-EINTR into KVM proper
Move KVM's morphing of pending signals into userspace exits into KVM proper, and drop the @vcpu param from xfer_to_guest_mode_handle_work(). How KVM responds to -EINTR is a detail that really belongs in KVM itself, and invoking kvm_handle_signal_exit() from kernel code creates an inverted module dependency. E.g. attempting to move kvm_handle_signal_exit() into kvm_main.c would generate an linker error when building kvm.ko as a module. Dropping KVM details will also converting the KVM "entry" code into a more generic virtualization framework so that it can be used when running as a Hyper-V root partition. Lastly, eliminating usage of "struct kvm_vcpu" outside of KVM is also nice to have for KVM x86 developers, as keeping the details of kvm_vcpu purely within KVM allows changing the layout of the structure without having to boot into a new kernel, e.g. allows rebuilding and reloading kvm.ko with a modified kvm_vcpu structure as part of debug/development. Signed-off-by: Sean Christopherson <seanjc@google.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Wei Liu <wei.liu@kernel.org> |
||
|
Vitaly Kuznetsov
|
7ad8c34f24 |
x86/hyperv: Add kexec/kdump support on Azure CVMs
Azure CVM instance types featuring a paravisor hang upon kdump. The investigation shows that makedumpfile causes a hang when it steps on a page which was previously share with the host (HVCALL_MODIFY_SPARSE_GPA_PAGE_HOST_VISIBILITY). The new kernel has no knowledge of these 'special' regions (which are Vmbus connection pages, GPADL buffers, ...). There are several ways to approach the issue: - Convey the knowledge about these regions to the new kernel somehow. - Unshare these regions before accessing in the new kernel (it is unclear if there's a way to query the status for a given GPA range). - Unshare these regions before jumping to the new kernel (which this patch implements). To make the procedure as robust as possible, store PFN ranges of shared regions in a linked list instead of storing GVAs and re-using hv_vtom_set_host_visibility(). This also allows to avoid memory allocation on the kdump/kexec path. Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Reviewed-by: Michael Kelley <mhklinux@outlook.com> Reviewed-by: Tianyu Lan <tiala@microsoft.com> Signed-off-by: Wei Liu <wei.liu@kernel.org> |
||
|
Linus Torvalds
|
7601d18be0 |
Merge tag 'core-core-2025-09-29' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull TIF bit unification updates from Thomas Gleixner: "A set of changes to consolidate the generic TIF (thread info flag) bits accross architectures. All architectures define the same set of generic TIF bits. This makes it pointlessly hard to add a new generic TIF bit or to change an existing one. Provide a generic variant and convert the architectures which utilize the generic entry code over to use it. The TIF space is divided into 16 generic bits and 16 architecture specific bits, which turned out to provide enough space on both sides" * tag 'core-core-2025-09-29' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: LoongArch: Fix bitflag conflict for TIF_FIXADE riscv: Use generic TIF bits loongarch: Use generic TIF bits s390/entry: Remove unused TIF flags s390: Use generic TIF bits x86: Use generic TIF bits asm-generic: Provide generic TIF infrastructure |
||
|
Linus Torvalds
|
22bdd6e68b |
Merge tag 'x86_apic_for_v6.18_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 SEV and apic updates from Borislav Petkov: - Add functionality to provide runtime firmware updates for the non-x86 parts of an AMD platform like the security processor (ASP) firmware, modules etc, for example. The intent being that these updates are interim, live fixups before a proper BIOS update can be attempted - Add guest support for AMD's Secure AVIC feature which gives encrypted guests the needed protection against a malicious hypervisor generating unexpected interrupts and injecting them into such guest, thus interfering with its operation in an unexpected and negative manner. The advantage of this scheme is that the guest determines which interrupts and when to accept them vs leaving that to the benevolence (or not) of the hypervisor - Strictly separate the startup code from the rest of the kernel where former is executed from the initial 1:1 mapping of memory. The problem was that the toolchain-generated version of the code was being executed from a different mapping of memory than what was "assumed" during code generation, needing an ever-growing pile of fixups for absolute memory references which are invalid in the early, 1:1 memory mapping during boot. The major advantage of this is that there's no need to check the 1:1 mapping portion of the code for absolute relocations anymore and get rid of the RIP_REL_REF() macro sprinkling all over the place. For more info, see Ard's very detailed writeup on this [1] - The usual cleanups and fixes Link: https://lore.kernel.org/r/CAMj1kXEzKEuePEiHB%2BHxvfQbFz0sTiHdn4B%2B%2BzVBJ2mhkPkQ4Q@mail.gmail.com [1] * tag 'x86_apic_for_v6.18_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (49 commits) x86/boot: Drop erroneous __init annotation from early_set_pages_state() crypto: ccp - Add AMD Seamless Firmware Servicing (SFS) driver crypto: ccp - Add new HV-Fixed page allocation/free API x86/sev: Add new dump_rmp parameter to snp_leak_pages() API x86/startup/sev: Document the CPUID flow in the boot #VC handler objtool: Ignore __pi___cfi_ prefixed symbols x86/sev: Zap snp_abort() x86/apic/savic: Do not use snp_abort() x86/boot: Get rid of the .head.text section x86/boot: Move startup code out of __head section efistub/x86: Remap inittext read-execute when needed x86/boot: Create a confined code area for startup code x86/kbuild: Incorporate boot/startup/ via Kbuild makefile x86/boot: Revert "Reject absolute references in .head.text" x86/boot: Check startup code for absence of absolute relocations objtool: Add action to check for absence of absolute relocations x86/sev: Export startup routines for later use x86/sev: Move __sev_[get|put]_ghcb() into separate noinstr object x86/sev: Provide PIC aliases for SEV related data objects x86/boot: Provide PIC aliases for 5-level paging related constants ... |
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Linus Torvalds
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2cb8eeaf00 |
Merge tag 'x86_cache_for_v6.18_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 resource control updates from Borislav Petkov: "Add support on AMD for assigning QoS bandwidth counters to resources (RMIDs) with the ability for those resources to be tracked by the counters as long as they're assigned to them. Previously, due to hw limitations, bandwidth counts from untracked resources would get lost when those resources are not tracked. Refactor the code and user interfaces to be able to also support other, similar features on ARM, for example" * tag 'x86_cache_for_v6.18_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (35 commits) fs/resctrl: Fix counter auto-assignment on mkdir with mbm_event enabled MAINTAINERS: resctrl: Add myself as reviewer x86/resctrl: Configure mbm_event mode if supported fs/resctrl: Introduce the interface to switch between monitor modes fs/resctrl: Disable BMEC event configuration when mbm_event mode is enabled fs/resctrl: Introduce the interface to modify assignments in a group fs/resctrl: Introduce mbm_L3_assignments to list assignments in a group fs/resctrl: Auto assign counters on mkdir and clean up on group removal fs/resctrl: Introduce mbm_assign_on_mkdir to enable assignments on mkdir fs/resctrl: Provide interface to update the event configurations fs/resctrl: Add event configuration directory under info/L3_MON/ fs/resctrl: Support counter read/reset with mbm_event assignment mode x86/resctrl: Implement resctrl_arch_reset_cntr() and resctrl_arch_cntr_read() x86/resctrl: Refactor resctrl_arch_rmid_read() fs/resctrl: Introduce counter ID read, reset calls in mbm_event mode fs/resctrl: Pass struct rdtgroup instead of individual members fs/resctrl: Add the functionality to unassign MBM events fs/resctrl: Add the functionality to assign MBM events x86,fs/resctrl: Implement resctrl_arch_config_cntr() to assign a counter with ABMC fs/resctrl: Introduce event configuration field in struct mon_evt ... |
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Linus Torvalds
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a65879b458 |
Merge tag 'x86_cpu_for_v6.18_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 cpuid updates from Borislav Petkov: - Make UMIP instruction detection more robust - Correct and cleanup AMD CPU topology detection; document the relevant CPUID leaves topology parsing precedence on AMD - Add support for running the kernel as guest on FreeBSD's Bhyve hypervisor - Cleanups and improvements * tag 'x86_cpu_for_v6.18_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/umip: Fix decoding of register forms of 0F 01 (SGDT and SIDT aliases) x86/umip: Check that the instruction opcode is at least two bytes Documentation/x86/topology: Detail CPUID leaves used for topology enumeration x86/cpu/topology: Define AMD64_CPUID_EXT_FEAT MSR x86/cpu/topology: Check for X86_FEATURE_XTOPOLOGY instead of passing has_xtopology x86/cpu/cacheinfo: Simplify cacheinfo_amd_init_llc_id() using _cpuid4_info x86/cpu: Rename and move CPU model entry for Diamond Rapids x86/cpu: Detect FreeBSD Bhyve hypervisor |
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Linus Torvalds
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d7ec0cf1cd |
Merge tag 'x86_bugs_for_v6.18_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 mitigation updates from Borislav Petkov: - Add VMSCAPE to the attack vector controls infrastructure - A bunch of the usual cleanups and fixlets, some of them resulting from fuzzing the different mitigation options * tag 'x86_bugs_for_v6.18_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/bugs: Report correct retbleed mitigation status x86/bugs: Fix reporting of LFENCE retpoline x86/bugs: Fix spectre_v2 forcing x86/bugs: Remove uses of cpu_mitigations_off() x86/bugs: Simplify SSB cmdline parsing x86/bugs: Use early_param() for spectre_v2 x86/bugs: Use early_param() for spectre_v2_user x86/bugs: Add attack vector controls for VMSCAPE x86/its: Move ITS indirect branch thunks to .text..__x86.indirect_thunk |
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Linus Torvalds
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d9c43b6e43 |
Merge tag 'ras_core_for_v6.18_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 RAS updates from Borislav Petkov:
- Unify and refactor the MCA arch side and better separate code
- Cleanup and simplify the AMD RAS side, unify code, drop unused stuff
* tag 'ras_core_for_v6.18_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/mce: Add a clear_bank() helper
x86/mce: Move machine_check_poll() status checks to helper functions
x86/mce: Separate global and per-CPU quirks
x86/mce: Do 'UNKNOWN' vendor check early
x86/mce: Define BSP-only SMCA init
x86/mce: Define BSP-only init
x86/mce: Set CR4.MCE last during init
x86/mce: Remove __mcheck_cpu_init_early()
x86/mce: Cleanup bank processing on init
x86/mce/amd: Put list_head in threshold_bank
x86/mce/amd: Remove smca_banks_map
x86/mce/amd: Remove return value for mce_threshold_{create,remove}_device()
x86/mce/amd: Rename threshold restart function
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Linus Torvalds
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bd91417a96 |
Merge tag 'x86_microcode_for_v6.18_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 microcode loading updates from Borislav Petkov: - Add infrastructure to be able to debug the microcode loader in a guest - Refresh Intel old microcode revisions * tag 'x86_microcode_for_v6.18_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/microcode: Add microcode loader debugging functionality x86/microcode: Add microcode= cmdline parsing x86/microcode/intel: Refresh the revisions that determine old_microcode |
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Linus Torvalds
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45d96dd2c6 |
Merge tag 'x86_asm_for_v6.18_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 asm update from Borislav Petkov: - Fix RDPID's output operand size in inline asm and use the insn mnemonic because the minimum binutils version supports it * tag 'x86_asm_for_v6.18_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/vdso: Fix output operand size of RDPID |
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Linus Torvalds
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163d9c6b33 |
Merge tag 'x86_build_for_v6.18_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 build updates from Borislav Petkov: - Remove and simplify a bunch of cc-option and compiler version checks in the build machinery now that the minimal version of both compilers supports them * tag 'x86_build_for_v6.18_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/Kconfig: Clean up LLVM version checks in IBT configurations x86/build: Remove cc-option from -mskip-rax-setup x86/build: Remove cc-option from -mno-fp-ret-in-387 x86/build: Clean up stack alignment flags in CC_FLAGS_FPU x86/build: Remove cc-option from stack alignment flags x86/build: Remove cc-option for GCC retpoline flags |
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Linus Torvalds
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98afd4dd3d |
Merge tag 'x86_misc_for_v6.18_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 instruction decoder update from Borislav Petkov: - Add instruction decoding support for the XOP-prefixed instruction set present on the AMD Bulldozer uarch [ These instructions don't normally happen, but a X86_NATIVE_CPU build on a bulldozer host can make the compiler then use these unusual instruction encodings ] * tag 'x86_misc_for_v6.18_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/insn: Add XOP prefix instructions decoder support |
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Linus Torvalds
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e4dcbdff11 |
Merge tag 'perf-core-2025-09-26' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull performance events updates from Ingo Molnar:
"Core perf code updates:
- Convert mmap() related reference counts to refcount_t. This is in
reaction to the recently fixed refcount bugs, which could have been
detected earlier and could have mitigated the bug somewhat (Thomas
Gleixner, Peter Zijlstra)
- Clean up and simplify the callchain code, in preparation for
sframes (Steven Rostedt, Josh Poimboeuf)
Uprobes updates:
- Add support to optimize usdt probes on x86-64, which gives a
substantial speedup (Jiri Olsa)
- Cleanups and fixes on x86 (Peter Zijlstra)
PMU driver updates:
- Various optimizations and fixes to the Intel PMU driver (Dapeng Mi)
Misc cleanups and fixes:
- Remove redundant __GFP_NOWARN (Qianfeng Rong)"
* tag 'perf-core-2025-09-26' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (57 commits)
selftests/bpf: Fix uprobe_sigill test for uprobe syscall error value
uprobes/x86: Return error from uprobe syscall when not called from trampoline
perf: Skip user unwind if the task is a kernel thread
perf: Simplify get_perf_callchain() user logic
perf: Use current->flags & PF_KTHREAD|PF_USER_WORKER instead of current->mm == NULL
perf: Have get_perf_callchain() return NULL if crosstask and user are set
perf: Remove get_perf_callchain() init_nr argument
perf/x86: Print PMU counters bitmap in x86_pmu_show_pmu_cap()
perf/x86/intel: Add ICL_FIXED_0_ADAPTIVE bit into INTEL_FIXED_BITS_MASK
perf/x86/intel: Change macro GLOBAL_CTRL_EN_PERF_METRICS to BIT_ULL(48)
perf/x86: Add PERF_CAP_PEBS_TIMING_INFO flag
perf/x86/intel: Fix IA32_PMC_x_CFG_B MSRs access error
perf/x86/intel: Use early_initcall() to hook bts_init()
uprobes: Remove redundant __GFP_NOWARN
selftests/seccomp: validate uprobe syscall passes through seccomp
seccomp: passthrough uprobe systemcall without filtering
selftests/bpf: Fix uprobe syscall shadow stack test
selftests/bpf: Change test_uretprobe_regs_change for uprobe and uretprobe
selftests/bpf: Add uprobe_regs_equal test
selftests/bpf: Add optimized usdt variant for basic usdt test
...
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Sean Christopherson
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6b36119b94 |
KVM: x86: Export KVM-internal symbols for sub-modules only
Rework almost all of KVM x86's exports to expose symbols only to KVM's
vendor modules, i.e. to kvm-{amd,intel}.ko. Keep the generic exports that
are guarded by CONFIG_KVM_EXTERNAL_WRITE_TRACKING=y, as they're explicitly
designed/intended for external usage.
Link: https://lore.kernel.org/r/20250919003303.1355064-6-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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Sean Christopherson
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6560468305 |
KVM: x86: Drop pointless exports of kvm_arch_xxx() hooks
Drop the exporting of several kvm_arch_xxx() hooks that are only called from arch-neutral code, i.e. that are only called from kvm.ko. Link: https://lore.kernel.org/r/20250919003303.1355064-5-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> |
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Sean Christopherson
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d273b52b6f |
KVM: x86: Move kvm_intr_is_single_vcpu() to lapic.c
Move kvm_intr_is_single_vcpu() to lapic.c, drop its export, and make its
"fast" helper local to lapic.c. kvm_intr_is_single_vcpu() is only usable
if the local APIC is in-kernel, i.e. it most definitely belongs in the
local APIC code.
No functional change intended.
Fixes:
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Sean Christopherson
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20c4892058 |
KVM: Export KVM-internal symbols for sub-modules only
Rework the vast majority of KVM's exports to expose symbols only to KVM
submodules, i.e. to x86's kvm-{amd,intel}.ko and PPC's kvm-{pr,hv}.ko.
With few exceptions, KVM's exported APIs are intended (and safe) for KVM-
internal usage only.
Keep kvm_get_kvm(), kvm_get_kvm_safe(), and kvm_put_kvm() as normal
exports, as they are needed by VFIO, and are generally safe for external
usage (though ideally even the get/put APIs would be KVM-internal, and
VFIO would pin a VM by grabbing a reference to its associated file).
Implement a framework in kvm_types.h in anticipation of providing a macro
to restrict KVM-specific kernel exports, i.e. to provide symbol exports
for KVM if and only if KVM is built as one or more modules.
Link: https://lore.kernel.org/r/20250919003303.1355064-3-seanjc@google.com
Cc: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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Paolo Bonzini
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12abeb81c8 |
Merge tag 'kvm-x86-cet-6.18' of https://github.com/kvm-x86/linux into HEAD
KVM x86 CET virtualization support for 6.18
Add support for virtualizing Control-flow Enforcement Technology (CET) on
Intel (Shadow Stacks and Indirect Branch Tracking) and AMD (Shadow Stacks).
CET is comprised of two distinct features, Shadow Stacks (SHSTK) and Indirect
Branch Tracking (IBT), that can be utilized by software to help provide
Control-flow integrity (CFI). SHSTK defends against backward-edge attacks
(a.k.a. Return-oriented programming (ROP)), while IBT defends against
forward-edge attacks (a.k.a. similarly CALL/JMP-oriented programming (COP/JOP)).
Attackers commonly use ROP and COP/JOP methodologies to redirect the control-
flow to unauthorized targets in order to execute small snippets of code,
a.k.a. gadgets, of the attackers choice. By chaining together several gadgets,
an attacker can perform arbitrary operations and circumvent the system's
defenses.
SHSTK defends against backward-edge attacks, which execute gadgets by modifying
the stack to branch to the attacker's target via RET, by providing a second
stack that is used exclusively to track control transfer operations. The
shadow stack is separate from the data/normal stack, and can be enabled
independently in user and kernel mode.
When SHSTK is is enabled, CALL instructions push the return address on both the
data and shadow stack. RET then pops the return address from both stacks and
compares the addresses. If the return addresses from the two stacks do not
match, the CPU generates a Control Protection (#CP) exception.
IBT defends against backward-edge attacks, which branch to gadgets by executing
indirect CALL and JMP instructions with attacker controlled register or memory
state, by requiring the target of indirect branches to start with a special
marker instruction, ENDBRANCH. If an indirect branch is executed and the next
instruction is not an ENDBRANCH, the CPU generates a #CP. Note, ENDBRANCH
behaves as a NOP if IBT is disabled or unsupported.
From a virtualization perspective, CET presents several problems. While SHSTK
and IBT have two layers of enabling, a global control in the form of a CR4 bit,
and a per-feature control in user and kernel (supervisor) MSRs (U_CET and S_CET
respectively), the {S,U}_CET MSRs can be context switched via XSAVES/XRSTORS.
Practically speaking, intercepting and emulating XSAVES/XRSTORS is not a viable
option due to complexity, and outright disallowing use of XSTATE to context
switch SHSTK/IBT state would render the features unusable to most guests.
To limit the overall complexity without sacrificing performance or usability,
simply ignore the potential virtualization hole, but ensure that all paths in
KVM treat SHSTK/IBT as usable by the guest if the feature is supported in
hardware, and the guest has access to at least one of SHSTK or IBT. I.e. allow
userspace to advertise one of SHSTK or IBT if both are supported in hardware,
even though doing so would allow a misbehaving guest to use the unadvertised
feature.
Fully emulating SHSTK and IBT would also require significant complexity, e.g.
to track and update branch state for IBT, and shadow stack state for SHSTK.
Given that emulating large swaths of the guest code stream isn't necessary on
modern CPUs, punt on emulating instructions that meaningful impact or consume
SHSTK or IBT. However, instead of doing nothing, explicitly reject emulation
of such instructions so that KVM's emulator can't be abused to circumvent CET.
Disable support for SHSTK and IBT if KVM is configured such that emulation of
arbitrary guest instructions may be required, specifically if Unrestricted
Guest (Intel only) is disabled, or if KVM will emulate a guest.MAXPHYADDR that
is smaller than host.MAXPHYADDR.
Lastly disable SHSTK support if shadow paging is enabled, as the protections
for the shadow stack are novel (shadow stacks require Writable=0,Dirty=1, so
that they can't be directly modified by software), i.e. would require
non-trivial support in the Shadow MMU.
Note, AMD CPUs currently only support SHSTK. Explicitly disable IBT support
so that KVM doesn't over-advertise if AMD CPUs add IBT, and virtualizing IBT
in SVM requires KVM modifications.
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