Pull x86 fixes from Borislav Petkov:
- Make sure clearing CPU buffers using VERW happens at the latest
possible point in the return-to-userspace path, otherwise memory
accesses after the VERW execution could cause data to land in CPU
buffers again
* tag 'x86_urgent_for_v6.8_rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
KVM/VMX: Move VERW closer to VMentry for MDS mitigation
KVM/VMX: Use BT+JNC, i.e. EFLAGS.CF to select VMRESUME vs. VMLAUNCH
x86/bugs: Use ALTERNATIVE() instead of mds_user_clear static key
x86/entry_32: Add VERW just before userspace transition
x86/entry_64: Add VERW just before userspace transition
x86/bugs: Add asm helpers for executing VERW
Daniel Borkmann says:
====================
pull-request: bpf 2024-02-22
The following pull-request contains BPF updates for your *net* tree.
We've added 11 non-merge commits during the last 24 day(s) which contain
a total of 15 files changed, 217 insertions(+), 17 deletions(-).
The main changes are:
1) Fix a syzkaller-triggered oops when attempting to read the vsyscall
page through bpf_probe_read_kernel and friends, from Hou Tao.
2) Fix a kernel panic due to uninitialized iter position pointer in
bpf_iter_task, from Yafang Shao.
3) Fix a race between bpf_timer_cancel_and_free and bpf_timer_cancel,
from Martin KaFai Lau.
4) Fix a xsk warning in skb_add_rx_frag() (under CONFIG_DEBUG_NET)
due to incorrect truesize accounting, from Sebastian Andrzej Siewior.
5) Fix a NULL pointer dereference in sk_psock_verdict_data_ready,
from Shigeru Yoshida.
6) Fix a resolve_btfids warning when bpf_cpumask symbol cannot be
resolved, from Hari Bathini.
bpf-for-netdev
* tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf:
bpf, sockmap: Fix NULL pointer dereference in sk_psock_verdict_data_ready()
selftests/bpf: Add negtive test cases for task iter
bpf: Fix an issue due to uninitialized bpf_iter_task
selftests/bpf: Test racing between bpf_timer_cancel_and_free and bpf_timer_cancel
bpf: Fix racing between bpf_timer_cancel_and_free and bpf_timer_cancel
selftest/bpf: Test the read of vsyscall page under x86-64
x86/mm: Disallow vsyscall page read for copy_from_kernel_nofault()
x86/mm: Move is_vsyscall_vaddr() into asm/vsyscall.h
bpf, scripts: Correct GPL license name
xsk: Add truesize to skb_add_rx_frag().
bpf: Fix warning for bpf_cpumask in verifier
====================
Link: https://lore.kernel.org/r/20240221231826.1404-1-daniel@iogearbox.net
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
The VERW mitigation at exit-to-user is enabled via a static branch
mds_user_clear. This static branch is never toggled after boot, and can
be safely replaced with an ALTERNATIVE() which is convenient to use in
asm.
Switch to ALTERNATIVE() to use the VERW mitigation late in exit-to-user
path. Also remove the now redundant VERW in exc_nmi() and
arch_exit_to_user_mode().
Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Link: https://lore.kernel.org/all/20240213-delay-verw-v8-4-a6216d83edb7%40linux.intel.com
MDS mitigation requires clearing the CPU buffers before returning to
user. This needs to be done late in the exit-to-user path. Current
location of VERW leaves a possibility of kernel data ending up in CPU
buffers for memory accesses done after VERW such as:
1. Kernel data accessed by an NMI between VERW and return-to-user can
remain in CPU buffers since NMI returning to kernel does not
execute VERW to clear CPU buffers.
2. Alyssa reported that after VERW is executed,
CONFIG_GCC_PLUGIN_STACKLEAK=y scrubs the stack used by a system
call. Memory accesses during stack scrubbing can move kernel stack
contents into CPU buffers.
3. When caller saved registers are restored after a return from
function executing VERW, the kernel stack accesses can remain in
CPU buffers(since they occur after VERW).
To fix this VERW needs to be moved very late in exit-to-user path.
In preparation for moving VERW to entry/exit asm code, create macros
that can be used in asm. Also make VERW patching depend on a new feature
flag X86_FEATURE_CLEAR_CPU_BUF.
Reported-by: Alyssa Milburn <alyssa.milburn@intel.com>
Suggested-by: Andrew Cooper <andrew.cooper3@citrix.com>
Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Link: https://lore.kernel.org/all/20240213-delay-verw-v8-1-a6216d83edb7%40linux.intel.com
We've had issues with gcc and 'asm goto' before, and we created a
'asm_volatile_goto()' macro for that in the past: see commits
3f0116c323 ("compiler/gcc4: Add quirk for 'asm goto' miscompilation
bug") and a9f180345f ("compiler/gcc4: Make quirk for
asm_volatile_goto() unconditional").
Then, much later, we ended up removing the workaround in commit
43c249ea0b ("compiler-gcc.h: remove ancient workaround for gcc PR
58670") because we no longer supported building the kernel with the
affected gcc versions, but we left the macro uses around.
Now, Sean Christopherson reports a new version of a very similar
problem, which is fixed by re-applying that ancient workaround. But the
problem in question is limited to only the 'asm goto with outputs'
cases, so instead of re-introducing the old workaround as-is, let's
rename and limit the workaround to just that much less common case.
It looks like there are at least two separate issues that all hit in
this area:
(a) some versions of gcc don't mark the asm goto as 'volatile' when it
has outputs:
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98619https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110420
which is easy to work around by just adding the 'volatile' by hand.
(b) Internal compiler errors:
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110422
which are worked around by adding the extra empty 'asm' as a
barrier, as in the original workaround.
but the problem Sean sees may be a third thing since it involves bad
code generation (not an ICE) even with the manually added 'volatile'.
but the same old workaround works for this case, even if this feels a
bit like voodoo programming and may only be hiding the issue.
Reported-and-tested-by: Sean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/all/20240208220604.140859-1-seanjc@google.com/
Cc: Nick Desaulniers <ndesaulniers@google.com>
Cc: Uros Bizjak <ubizjak@gmail.com>
Cc: Jakub Jelinek <jakub@redhat.com>
Cc: Andrew Pinski <quic_apinski@quicinc.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull kvm fixes from Paolo Bonzini:
"x86 guest:
- Avoid false positive for check that only matters on AMD processors
x86:
- Give a hint when Win2016 might fail to boot due to XSAVES &&
!XSAVEC configuration
- Do not allow creating an in-kernel PIT unless an IOAPIC already
exists
RISC-V:
- Allow ISA extensions that were enabled for bare metal in 6.8 (Zbc,
scalar and vector crypto, Zfh[min], Zihintntl, Zvfh[min], Zfa)
S390:
- fix CC for successful PQAP instruction
- fix a race when creating a shadow page"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
x86/coco: Define cc_vendor without CONFIG_ARCH_HAS_CC_PLATFORM
x86/kvm: Fix SEV check in sev_map_percpu_data()
KVM: x86: Give a hint when Win2016 might fail to boot due to XSAVES erratum
KVM: x86: Check irqchip mode before create PIT
KVM: riscv: selftests: Add Zfa extension to get-reg-list test
RISC-V: KVM: Allow Zfa extension for Guest/VM
KVM: riscv: selftests: Add Zvfh[min] extensions to get-reg-list test
RISC-V: KVM: Allow Zvfh[min] extensions for Guest/VM
KVM: riscv: selftests: Add Zihintntl extension to get-reg-list test
RISC-V: KVM: Allow Zihintntl extension for Guest/VM
KVM: riscv: selftests: Add Zfh[min] extensions to get-reg-list test
RISC-V: KVM: Allow Zfh[min] extensions for Guest/VM
KVM: riscv: selftests: Add vector crypto extensions to get-reg-list test
RISC-V: KVM: Allow vector crypto extensions for Guest/VM
KVM: riscv: selftests: Add scaler crypto extensions to get-reg-list test
RISC-V: KVM: Allow scalar crypto extensions for Guest/VM
KVM: riscv: selftests: Add Zbc extension to get-reg-list test
RISC-V: KVM: Allow Zbc extension for Guest/VM
KVM: s390: fix cc for successful PQAP
KVM: s390: vsie: fix race during shadow creation
After commit a9ef277488 ("x86/kvm: Fix SEV check in
sev_map_percpu_data()"), there is a build error when building
x86_64_defconfig with GCOV using LLVM:
ld.lld: error: undefined symbol: cc_vendor
>>> referenced by kvm.c
>>> arch/x86/kernel/kvm.o:(kvm_smp_prepare_boot_cpu) in archive vmlinux.a
which corresponds to
if (cc_vendor != CC_VENDOR_AMD ||
!cc_platform_has(CC_ATTR_GUEST_MEM_ENCRYPT))
return;
Without GCOV, clang is able to eliminate the use of cc_vendor because
cc_platform_has() evaluates to false when CONFIG_ARCH_HAS_CC_PLATFORM is
not set, meaning that if statement will be true no matter what value
cc_vendor has.
With GCOV, the instrumentation keeps the use of cc_vendor around for
code coverage purposes but cc_vendor is only declared, not defined,
without CONFIG_ARCH_HAS_CC_PLATFORM, leading to the build error above.
Provide a macro definition of cc_vendor when CONFIG_ARCH_HAS_CC_PLATFORM
is not set with a value of CC_VENDOR_NONE, so that the first condition
can always be evaluated/eliminated at compile time, avoiding the build
error altogether. This is very similar to the situation prior to
commit da86eb9611 ("x86/coco: Get rid of accessor functions").
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Acked-by: Borislav Petkov (AMD) <bp@alien8.de>
Message-Id: <20240202-provide-cc_vendor-without-arch_has_cc_platform-v1-1-09ad5f2a3099@kernel.org>
Fixes: a9ef277488 ("x86/kvm: Fix SEV check in sev_map_percpu_data()", 2024-01-31)
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Since commit b0563468ee ("x86/CPU/AMD: Disable XSAVES on AMD family 0x17")
kernel unconditionally clears the XSAVES CPU feature bit on Zen1/2 CPUs.
Because KVM CPU caps are initialized from the kernel boot CPU features this
makes the XSAVES feature also unavailable for KVM guests in this case.
At the same time the XSAVEC feature is left enabled.
Unfortunately, having XSAVEC but no XSAVES in CPUID breaks Hyper-V enabled
Windows Server 2016 VMs that have more than one vCPU.
Let's at least give users hint in the kernel log what could be wrong since
these VMs currently simply hang at boot with a black screen - giving no
clue what suddenly broke them and how to make them work again.
Trigger the kernel message hint based on the particular guest ID written to
the Guest OS Identity Hyper-V MSR implemented by KVM.
Defer this check to when the L1 Hyper-V hypervisor enables SVM in EFER
since we want to limit this message to Hyper-V enabled Windows guests only
(Windows session running nested as L2) but the actual Guest OS Identity MSR
write is done by L1 and happens before it enables SVM.
Fixes: b0563468ee ("x86/CPU/AMD: Disable XSAVES on AMD family 0x17")
Signed-off-by: Maciej S. Szmigiero <maciej.szmigiero@oracle.com>
Message-Id: <b83ab45c5e239e5d148b0ae7750133a67ac9575c.1706127425.git.maciej.szmigiero@oracle.com>
[Move some checks before mutex_lock(), rename function. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Pull misc fixes from Andrew Morton:
"22 hotfixes. 11 are cc:stable and the remainder address post-6.7
issues or aren't considered appropriate for backporting"
* tag 'mm-hotfixes-stable-2024-01-28-23-21' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (22 commits)
mm: thp_get_unmapped_area must honour topdown preference
mm: huge_memory: don't force huge page alignment on 32 bit
userfaultfd: fix mmap_changing checking in mfill_atomic_hugetlb
selftests/mm: ksm_tests should only MADV_HUGEPAGE valid memory
scs: add CONFIG_MMU dependency for vfree_atomic()
mm/memory: fix folio_set_dirty() vs. folio_mark_dirty() in zap_pte_range()
mm/huge_memory: fix folio_set_dirty() vs. folio_mark_dirty()
selftests/mm: Update va_high_addr_switch.sh to check CPU for la57 flag
selftests: mm: fix map_hugetlb failure on 64K page size systems
MAINTAINERS: supplement of zswap maintainers update
stackdepot: make fast paths lock-less again
stackdepot: add stats counters exported via debugfs
mm, kmsan: fix infinite recursion due to RCU critical section
mm/writeback: fix possible divide-by-zero in wb_dirty_limits(), again
selftests/mm: switch to bash from sh
MAINTAINERS: add man-pages git trees
mm: memcontrol: don't throttle dying tasks on memory.high
mm: mmap: map MAP_STACK to VM_NOHUGEPAGE
uprobes: use pagesize-aligned virtual address when replacing pages
selftests/mm: mremap_test: fix build warning
...
Alexander Potapenko writes in [1]: "For every memory access in the code
instrumented by KMSAN we call kmsan_get_metadata() to obtain the metadata
for the memory being accessed. For virtual memory the metadata pointers
are stored in the corresponding `struct page`, therefore we need to call
virt_to_page() to get them.
According to the comment in arch/x86/include/asm/page.h,
virt_to_page(kaddr) returns a valid pointer iff virt_addr_valid(kaddr) is
true, so KMSAN needs to call virt_addr_valid() as well.
To avoid recursion, kmsan_get_metadata() must not call instrumented code,
therefore ./arch/x86/include/asm/kmsan.h forks parts of
arch/x86/mm/physaddr.c to check whether a virtual address is valid or not.
But the introduction of rcu_read_lock() to pfn_valid() added instrumented
RCU API calls to virt_to_page_or_null(), which is called by
kmsan_get_metadata(), so there is an infinite recursion now. I do not
think it is correct to stop that recursion by doing
kmsan_enter_runtime()/kmsan_exit_runtime() in kmsan_get_metadata(): that
would prevent instrumented functions called from within the runtime from
tracking the shadow values, which might introduce false positives."
Fix the issue by switching pfn_valid() to the _sched() variant of
rcu_read_lock/unlock(), which does not require calling into RCU. Given
the critical section in pfn_valid() is very small, this is a reasonable
trade-off (with preemptible RCU).
KMSAN further needs to be careful to suppress calls into the scheduler,
which would be another source of recursion. This can be done by wrapping
the call to pfn_valid() into preempt_disable/enable_no_resched(). The
downside is that this sacrifices breaking scheduling guarantees; however,
a kernel compiled with KMSAN has already given up any performance
guarantees due to being heavily instrumented.
Note, KMSAN code already disables tracing via Makefile, and since mmzone.h
is included, it is not necessary to use the notrace variant, which is
generally preferred in all other cases.
Link: https://lkml.kernel.org/r/20240115184430.2710652-1-glider@google.com [1]
Link: https://lkml.kernel.org/r/20240118110022.2538350-1-elver@google.com
Fixes: 5ec8e8ea8b ("mm/sparsemem: fix race in accessing memory_section->usage")
Signed-off-by: Marco Elver <elver@google.com>
Reported-by: Alexander Potapenko <glider@google.com>
Reported-by: syzbot+93a9e8a3dea8d6085e12@syzkaller.appspotmail.com
Reviewed-by: Alexander Potapenko <glider@google.com>
Tested-by: Alexander Potapenko <glider@google.com>
Cc: Charan Teja Kalla <quic_charante@quicinc.com>
Cc: Borislav Petkov (AMD) <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Presently ia32 registers stored in ptregs are unconditionally cast to
unsigned int by the ia32 stub. They are then cast to long when passed to
__se_sys*, but will not be sign extended.
This takes the sign of the syscall argument into account in the ia32
stub. It still casts to unsigned int to avoid implementation specific
behavior. However then casts to int or unsigned int as necessary. So that
the following cast to long sign extends the value.
This fixes the io_pgetevents02 LTP test when compiled with -m32. Presently
the systemcall io_pgetevents_time64() unexpectedly accepts -1 for the
maximum number of events.
It doesn't appear other systemcalls with signed arguments are effected
because they all have compat variants defined and wired up.
Fixes: ebeb8c82ff ("syscalls/x86: Use 'struct pt_regs' based syscall calling for IA32_EMULATION and x32")
Suggested-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Richard Palethorpe <rpalethorpe@suse.com>
Signed-off-by: Nikolay Borisov <nik.borisov@suse.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20240110130122.3836513-1-nik.borisov@suse.com
Link: https://lore.kernel.org/ltp/20210921130127.24131-1-rpalethorpe@suse.com/
Pull x86 TDX updates from Dave Hansen:
"This contains the initial support for host-side TDX support so that
KVM can run TDX-protected guests. This does not include the actual
KVM-side support which will come from the KVM folks. The TDX host
interactions with kexec also needs to be ironed out before this is
ready for prime time, so this code is currently Kconfig'd off when
kexec is on.
The majority of the code here is the kernel telling the TDX module
which memory to protect and handing some additional memory over to it
to use to store TDX module metadata. That sounds pretty simple, but
the TDX architecture is rather flexible and it takes quite a bit of
back-and-forth to say, "just protect all memory, please."
There is also some code tacked on near the end of the series to handle
a hardware erratum. The erratum can make software bugs such as a
kernel write to TDX-protected memory cause a machine check and
masquerade as a real hardware failure. The erratum handling watches
out for these and tries to provide nicer user errors"
* tag 'x86_tdx_for_6.8' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (21 commits)
x86/virt/tdx: Make TDX host depend on X86_MCE
x86/virt/tdx: Disable TDX host support when kexec is enabled
Documentation/x86: Add documentation for TDX host support
x86/mce: Differentiate real hardware #MCs from TDX erratum ones
x86/cpu: Detect TDX partial write machine check erratum
x86/virt/tdx: Handle TDX interaction with sleep and hibernation
x86/virt/tdx: Initialize all TDMRs
x86/virt/tdx: Configure global KeyID on all packages
x86/virt/tdx: Configure TDX module with the TDMRs and global KeyID
x86/virt/tdx: Designate reserved areas for all TDMRs
x86/virt/tdx: Allocate and set up PAMTs for TDMRs
x86/virt/tdx: Fill out TDMRs to cover all TDX memory regions
x86/virt/tdx: Add placeholder to construct TDMRs to cover all TDX memory regions
x86/virt/tdx: Get module global metadata for module initialization
x86/virt/tdx: Use all system memory when initializing TDX module as TDX memory
x86/virt/tdx: Add skeleton to enable TDX on demand
x86/virt/tdx: Add SEAMCALL error printing for module initialization
x86/virt/tdx: Handle SEAMCALL no entropy error in common code
x86/virt/tdx: Make INTEL_TDX_HOST depend on X86_X2APIC
x86/virt/tdx: Define TDX supported page sizes as macros
...
Pull driver core updates from Greg KH:
"Here are the set of driver core and kernfs changes for 6.8-rc1.
Nothing major in here this release cycle, just lots of small cleanups
and some tweaks on kernfs that in the very end, got reverted and will
come back in a safer way next release cycle.
Included in here are:
- more driver core 'const' cleanups and fixes
- fw_devlink=rpm is now the default behavior
- kernfs tiny changes to remove some string functions
- cpu handling in the driver core is updated to work better on many
systems that add topologies and cpus after booting
- other minor changes and cleanups
All of the cpu handling patches have been acked by the respective
maintainers and are coming in here in one series. Everything has been
in linux-next for a while with no reported issues"
* tag 'driver-core-6.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (51 commits)
Revert "kernfs: convert kernfs_idr_lock to an irq safe raw spinlock"
kernfs: convert kernfs_idr_lock to an irq safe raw spinlock
class: fix use-after-free in class_register()
PM: clk: make pm_clk_add_notifier() take a const pointer
EDAC: constantify the struct bus_type usage
kernfs: fix reference to renamed function
driver core: device.h: fix Excess kernel-doc description warning
driver core: class: fix Excess kernel-doc description warning
driver core: mark remaining local bus_type variables as const
driver core: container: make container_subsys const
driver core: bus: constantify subsys_register() calls
driver core: bus: make bus_sort_breadthfirst() take a const pointer
kernfs: d_obtain_alias(NULL) will do the right thing...
driver core: Better advertise dev_err_probe()
kernfs: Convert kernfs_path_from_node_locked() from strlcpy() to strscpy()
kernfs: Convert kernfs_name_locked() from strlcpy() to strscpy()
kernfs: Convert kernfs_walk_ns() from strlcpy() to strscpy()
initramfs: Expose retained initrd as sysfs file
fs/kernfs/dir: obey S_ISGID
kernel/cgroup: use kernfs_create_dir_ns()
...
Pull kvm updates from Paolo Bonzini:
"Generic:
- Use memdup_array_user() to harden against overflow.
- Unconditionally advertise KVM_CAP_DEVICE_CTRL for all
architectures.
- Clean up Kconfigs that all KVM architectures were selecting
- New functionality around "guest_memfd", a new userspace API that
creates an anonymous file and returns a file descriptor that refers
to it. guest_memfd files are bound to their owning virtual machine,
cannot be mapped, read, or written by userspace, and cannot be
resized. guest_memfd files do however support PUNCH_HOLE, which can
be used to switch a memory area between guest_memfd and regular
anonymous memory.
- New ioctl KVM_SET_MEMORY_ATTRIBUTES allowing userspace to specify
per-page attributes for a given page of guest memory; right now the
only attribute is whether the guest expects to access memory via
guest_memfd or not, which in Confidential SVMs backed by SEV-SNP,
TDX or ARM64 pKVM is checked by firmware or hypervisor that
guarantees confidentiality (AMD PSP, Intel TDX module, or EL2 in
the case of pKVM).
x86:
- Support for "software-protected VMs" that can use the new
guest_memfd and page attributes infrastructure. This is mostly
useful for testing, since there is no pKVM-like infrastructure to
provide a meaningfully reduced TCB.
- Fix a relatively benign off-by-one error when splitting huge pages
during CLEAR_DIRTY_LOG.
- Fix a bug where KVM could incorrectly test-and-clear dirty bits in
non-leaf TDP MMU SPTEs if a racing thread replaces a huge SPTE with
a non-huge SPTE.
- Use more generic lockdep assertions in paths that don't actually
care about whether the caller is a reader or a writer.
- let Xen guests opt out of having PV clock reported as "based on a
stable TSC", because some of them don't expect the "TSC stable" bit
(added to the pvclock ABI by KVM, but never set by Xen) to be set.
- Revert a bogus, made-up nested SVM consistency check for
TLB_CONTROL.
- Advertise flush-by-ASID support for nSVM unconditionally, as KVM
always flushes on nested transitions, i.e. always satisfies flush
requests. This allows running bleeding edge versions of VMware
Workstation on top of KVM.
- Sanity check that the CPU supports flush-by-ASID when enabling SEV
support.
- On AMD machines with vNMI, always rely on hardware instead of
intercepting IRET in some cases to detect unmasking of NMIs
- Support for virtualizing Linear Address Masking (LAM)
- Fix a variety of vPMU bugs where KVM fail to stop/reset counters
and other state prior to refreshing the vPMU model.
- Fix a double-overflow PMU bug by tracking emulated counter events
using a dedicated field instead of snapshotting the "previous"
counter. If the hardware PMC count triggers overflow that is
recognized in the same VM-Exit that KVM manually bumps an event
count, KVM would pend PMIs for both the hardware-triggered overflow
and for KVM-triggered overflow.
- Turn off KVM_WERROR by default for all configs so that it's not
inadvertantly enabled by non-KVM developers, which can be
problematic for subsystems that require no regressions for W=1
builds.
- Advertise all of the host-supported CPUID bits that enumerate
IA32_SPEC_CTRL "features".
- Don't force a masterclock update when a vCPU synchronizes to the
current TSC generation, as updating the masterclock can cause
kvmclock's time to "jump" unexpectedly, e.g. when userspace
hotplugs a pre-created vCPU.
- Use RIP-relative address to read kvm_rebooting in the VM-Enter
fault paths, partly as a super minor optimization, but mostly to
make KVM play nice with position independent executable builds.
- Guard KVM-on-HyperV's range-based TLB flush hooks with an #ifdef on
CONFIG_HYPERV as a minor optimization, and to self-document the
code.
- Add CONFIG_KVM_HYPERV to allow disabling KVM support for HyperV
"emulation" at build time.
ARM64:
- LPA2 support, adding 52bit IPA/PA capability for 4kB and 16kB base
granule sizes. Branch shared with the arm64 tree.
- Large Fine-Grained Trap rework, bringing some sanity to the
feature, although there is more to come. This comes with a prefix
branch shared with the arm64 tree.
- Some additional Nested Virtualization groundwork, mostly
introducing the NV2 VNCR support and retargetting the NV support to
that version of the architecture.
- A small set of vgic fixes and associated cleanups.
Loongarch:
- Optimization for memslot hugepage checking
- Cleanup and fix some HW/SW timer issues
- Add LSX/LASX (128bit/256bit SIMD) support
RISC-V:
- KVM_GET_REG_LIST improvement for vector registers
- Generate ISA extension reg_list using macros in get-reg-list
selftest
- Support for reporting steal time along with selftest
s390:
- Bugfixes
Selftests:
- Fix an annoying goof where the NX hugepage test prints out garbage
instead of the magic token needed to run the test.
- Fix build errors when a header is delete/moved due to a missing
flag in the Makefile.
- Detect if KVM bugged/killed a selftest's VM and print out a helpful
message instead of complaining that a random ioctl() failed.
- Annotate the guest printf/assert helpers with __printf(), and fix
the various bugs that were lurking due to lack of said annotation"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (185 commits)
x86/kvm: Do not try to disable kvmclock if it was not enabled
KVM: x86: add missing "depends on KVM"
KVM: fix direction of dependency on MMU notifiers
KVM: introduce CONFIG_KVM_COMMON
KVM: arm64: Add missing memory barriers when switching to pKVM's hyp pgd
KVM: arm64: vgic-its: Avoid potential UAF in LPI translation cache
RISC-V: KVM: selftests: Add get-reg-list test for STA registers
RISC-V: KVM: selftests: Add steal_time test support
RISC-V: KVM: selftests: Add guest_sbi_probe_extension
RISC-V: KVM: selftests: Move sbi_ecall to processor.c
RISC-V: KVM: Implement SBI STA extension
RISC-V: KVM: Add support for SBI STA registers
RISC-V: KVM: Add support for SBI extension registers
RISC-V: KVM: Add SBI STA info to vcpu_arch
RISC-V: KVM: Add steal-update vcpu request
RISC-V: KVM: Add SBI STA extension skeleton
RISC-V: paravirt: Implement steal-time support
RISC-V: Add SBI STA extension definitions
RISC-V: paravirt: Add skeleton for pv-time support
RISC-V: KVM: Fix indentation in kvm_riscv_vcpu_set_reg_csr()
...
Pull networking updates from Paolo Abeni:
"The most interesting thing is probably the networking structs
reorganization and a significant amount of changes is around
self-tests.
Core & protocols:
- Analyze and reorganize core networking structs (socks, netdev,
netns, mibs) to optimize cacheline consumption and set up build
time warnings to safeguard against future header changes
This improves TCP performances with many concurrent connections up
to 40%
- Add page-pool netlink-based introspection, exposing the memory
usage and recycling stats. This helps indentify bad PP users and
possible leaks
- Refine TCP/DCCP source port selection to no longer favor even
source port at connect() time when IP_LOCAL_PORT_RANGE is set. This
lowers the time taken by connect() for hosts having many active
connections to the same destination
- Refactor the TCP bind conflict code, shrinking related socket
structs
- Refactor TCP SYN-Cookie handling, as a preparation step to allow
arbitrary SYN-Cookie processing via eBPF
- Tune optmem_max for 0-copy usage, increasing the default value to
128KB and namespecifying it
- Allow coalescing for cloned skbs coming from page pools, improving
RX performances with some common configurations
- Reduce extension header parsing overhead at GRO time
- Add bridge MDB bulk deletion support, allowing user-space to
request the deletion of matching entries
- Reorder nftables struct members, to keep data accessed by the
datapath first
- Introduce TC block ports tracking and use. This allows supporting
multicast-like behavior at the TC layer
- Remove UAPI support for retired TC qdiscs (dsmark, CBQ and ATM) and
classifiers (RSVP and tcindex)
- More data-race annotations
- Extend the diag interface to dump TCP bound-only sockets
- Conditional notification of events for TC qdisc class and actions
- Support for WPAN dynamic associations with nearby devices, to form
a sub-network using a specific PAN ID
- Implement SMCv2.1 virtual ISM device support
- Add support for Batman-avd mulicast packet type
BPF:
- Tons of verifier improvements:
- BPF register bounds logic and range support along with a large
test suite
- log improvements
- complete precision tracking support for register spills
- track aligned STACK_ZERO cases as imprecise spilled registers.
This improves the verifier "instructions processed" metric from
single digit to 50-60% for some programs
- support for user's global BPF subprogram arguments with few
commonly requested annotations for a better developer
experience
- support tracking of BPF_JNE which helps cases when the compiler
transforms (unsigned) "a > 0" into "if a == 0 goto xxx" and the
like
- several fixes
- Add initial TX metadata implementation for AF_XDP with support in
mlx5 and stmmac drivers. Two types of offloads are supported right
now, that is, TX timestamp and TX checksum offload
- Fix kCFI bugs in BPF all forms of indirect calls from BPF into
kernel and from kernel into BPF work with CFI enabled. This allows
BPF to work with CONFIG_FINEIBT=y
- Change BPF verifier logic to validate global subprograms lazily
instead of unconditionally before the main program, so they can be
guarded using BPF CO-RE techniques
- Support uid/gid options when mounting bpffs
- Add a new kfunc which acquires the associated cgroup of a task
within a specific cgroup v1 hierarchy where the latter is
identified by its id
- Extend verifier to allow bpf_refcount_acquire() of a map value
field obtained via direct load which is a use-case needed in
sched_ext
- Add BPF link_info support for uprobe multi link along with bpftool
integration for the latter
- Support for VLAN tag in XDP hints
- Remove deprecated bpfilter kernel leftovers given the project is
developed in user-space (https://github.com/facebook/bpfilter)
Misc:
- Support for parellel TC self-tests execution
- Increase MPTCP self-tests coverage
- Updated the bridge documentation, including several so-far
undocumented features
- Convert all the net self-tests to run in unique netns, to avoid
random failures due to conflict and allow concurrent runs
- Add TCP-AO self-tests
- Add kunit tests for both cfg80211 and mac80211
- Autogenerate Netlink families documentation from YAML spec
- Add yml-gen support for fixed headers and recursive nests, the tool
can now generate user-space code for all genetlink families for
which we have specs
- A bunch of additional module descriptions fixes
- Catch incorrect freeing of pages belonging to a page pool
Driver API:
- Rust abstractions for network PHY drivers; do not cover yet the
full C API, but already allow implementing functional PHY drivers
in rust
- Introduce queue and NAPI support in the netdev Netlink interface,
allowing complete access to the device <> NAPIs <> queues
relationship
- Introduce notifications filtering for devlink to allow control
application scale to thousands of instances
- Improve PHY validation, requesting rate matching information for
each ethtool link mode supported by both the PHY and host
- Add support for ethtool symmetric-xor RSS hash
- ACPI based Wifi band RFI (WBRF) mitigation feature for the AMD
platform
- Expose pin fractional frequency offset value over new DPLL generic
netlink attribute
- Convert older drivers to platform remove callback returning void
- Add support for PHY package MMD read/write
New hardware / drivers:
- Ethernet:
- Octeon CN10K devices
- Broadcom 5760X P7
- Qualcomm SM8550 SoC
- Texas Instrument DP83TG720S PHY
- Bluetooth:
- IMC Networks Bluetooth radio
Removed:
- WiFi:
- libertas 16-bit PCMCIA support
- Atmel at76c50x drivers
- HostAP ISA/PCMCIA style 802.11b driver
- zd1201 802.11b USB dongles
- Orinoco ISA/PCMCIA 802.11b driver
- Aviator/Raytheon driver
- Planet WL3501 driver
- RNDIS USB 802.11b driver
Driver updates:
- Ethernet high-speed NICs:
- Intel (100G, ice, idpf):
- allow one by one port representors creation and removal
- add temperature and clock information reporting
- add get/set for ethtool's header split ringparam
- add again FW logging
- adds support switchdev hardware packet mirroring
- iavf: implement symmetric-xor RSS hash
- igc: add support for concurrent physical and free-running
timers
- i40e: increase the allowable descriptors
- nVidia/Mellanox:
- Preparation for Socket-Direct multi-dev netdev. That will
allow in future releases combining multiple PFs devices
attached to different NUMA nodes under the same netdev
- Broadcom (bnxt):
- TX completion handling improvements
- add basic ntuple filter support
- reduce MSIX vectors usage for MQPRIO offload
- add VXLAN support, USO offload and TX coalesce completion
for P7
- Marvell Octeon EP:
- xmit-more support
- add PF-VF mailbox support and use it for FW notifications
for VFs
- Wangxun (ngbe/txgbe):
- implement ethtool functions to operate pause param, ring
param, coalesce channel number and msglevel
- Netronome/Corigine (nfp):
- add flow-steering support
- support UDP segmentation offload
- Ethernet NICs embedded, slower, virtual:
- Xilinx AXI: remove duplicate DMA code adopting the dma engine
driver
- stmmac: add support for HW-accelerated VLAN stripping
- TI AM654x sw: add mqprio, frame preemption & coalescing
- gve: add support for non-4k page sizes.
- virtio-net: support dynamic coalescing moderation
- nVidia/Mellanox Ethernet datacenter switches:
- allow firmware upgrade without a reboot
- more flexible support for bridge flooding via the compressed
FID flooding mode
- Ethernet embedded switches:
- Microchip:
- fine-tune flow control and speed configurations in KSZ8xxx
- KSZ88X3: enable setting rmii reference
- Renesas:
- add jumbo frames support
- Marvell:
- 88E6xxx: add "eth-mac" and "rmon" stats support
- Ethernet PHYs:
- aquantia: add firmware load support
- at803x: refactor the driver to simplify adding support for more
chip variants
- NXP C45 TJA11xx: Add MACsec offload support
- Wifi:
- MediaTek (mt76):
- NVMEM EEPROM improvements
- mt7996 Extremely High Throughput (EHT) improvements
- mt7996 Wireless Ethernet Dispatcher (WED) support
- mt7996 36-bit DMA support
- Qualcomm (ath12k):
- support for a single MSI vector
- WCN7850: support AP mode
- Intel (iwlwifi):
- new debugfs file fw_dbg_clear
- allow concurrent P2P operation on DFS channels
- Bluetooth:
- QCA2066: support HFP offload
- ISO: more broadcast-related improvements
- NXP: better recovery in case receiver/transmitter get out of sync"
* tag 'net-next-6.8' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1714 commits)
lan78xx: remove redundant statement in lan78xx_get_eee
lan743x: remove redundant statement in lan743x_ethtool_get_eee
bnxt_en: Fix RCU locking for ntuple filters in bnxt_rx_flow_steer()
bnxt_en: Fix RCU locking for ntuple filters in bnxt_srxclsrldel()
bnxt_en: Remove unneeded variable in bnxt_hwrm_clear_vnic_filter()
tcp: Revert no longer abort SYN_SENT when receiving some ICMP
Revert "mlx5 updates 2023-12-20"
Revert "net: stmmac: Enable Per DMA Channel interrupt"
ipvlan: Remove usage of the deprecated ida_simple_xx() API
ipvlan: Fix a typo in a comment
net/sched: Remove ipt action tests
net: stmmac: Use interrupt mode INTM=1 for per channel irq
net: stmmac: Add support for TX/RX channel interrupt
net: stmmac: Make MSI interrupt routine generic
dt-bindings: net: snps,dwmac: per channel irq
net: phy: at803x: make read_status more generic
net: phy: at803x: add support for cdt cross short test for qca808x
net: phy: at803x: refactor qca808x cable test get status function
net: phy: at803x: generalize cdt fault length function
net: ethernet: cortina: Drop TSO support
...
Pull asm-generic cleanups from Arnd Bergmann:
"A series from Baoquan He cleans up the asm-generic/io.h to remove the
ioremap_uc() definition from everything except x86, which still needs
it for pre-PAT systems. This series notably contains a patch from
Jiaxun Yang that converts MIPS to use asm-generic/io.h like every
other architecture does, enabling future cleanups.
Some of my own patches fix -Wmissing-prototype warnings in
architecture specific code across several architectures. This is now
needed as the warning is enabled by default. There are still some
remaining warnings in minor platforms, but the series should catch
most of the widely used ones make them more consistent with one
another.
David McKay fixes a bug in __generic_cmpxchg_local() when this is used
on 64-bit architectures. This could currently only affect parisc64 and
sparc64.
Additional cleanups address from Linus Walleij, Uwe Kleine-König,
Thomas Huth, and Kefeng Wang help reduce unnecessary inconsistencies
between architectures"
* tag 'asm-generic-6.8' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic:
asm-generic: Fix 32 bit __generic_cmpxchg_local
Hexagon: Make pfn accessors statics inlines
ARC: mm: Make virt_to_pfn() a static inline
mips: remove extraneous asm-generic/iomap.h include
sparc: Use $(kecho) to announce kernel images being ready
arm64: vdso32: Define BUILD_VDSO32_64 to correct prototypes
csky: fix arch_jump_label_transform_static override
arch: add do_page_fault prototypes
arch: add missing prepare_ftrace_return() prototypes
arch: vdso: consolidate gettime prototypes
arch: include linux/cpu.h for trap_init() prototype
arch: fix asm-offsets.c building with -Wmissing-prototypes
arch: consolidate arch_irq_work_raise prototypes
hexagon: Remove CONFIG_HEXAGON_ARCH_VERSION from uapi header
asm/io: remove unnecessary xlate_dev_mem_ptr() and unxlate_dev_mem_ptr()
mips: io: remove duplicated codes
arch/*/io.h: remove ioremap_uc in some architectures
mips: add <asm-generic/io.h> including
Pull header cleanups from Kent Overstreet:
"The goal is to get sched.h down to a type only header, so the main
thing happening in this patchset is splitting out various _types.h
headers and dependency fixups, as well as moving some things out of
sched.h to better locations.
This is prep work for the memory allocation profiling patchset which
adds new sched.h interdepencencies"
* tag 'header_cleanup-2024-01-10' of https://evilpiepirate.org/git/bcachefs: (51 commits)
Kill sched.h dependency on rcupdate.h
kill unnecessary thread_info.h include
Kill unnecessary kernel.h include
preempt.h: Kill dependency on list.h
rseq: Split out rseq.h from sched.h
LoongArch: signal.c: add header file to fix build error
restart_block: Trim includes
lockdep: move held_lock to lockdep_types.h
sem: Split out sem_types.h
uidgid: Split out uidgid_types.h
seccomp: Split out seccomp_types.h
refcount: Split out refcount_types.h
uapi/linux/resource.h: fix include
x86/signal: kill dependency on time.h
syscall_user_dispatch.h: split out *_types.h
mm_types_task.h: Trim dependencies
Split out irqflags_types.h
ipc: Kill bogus dependency on spinlock.h
shm: Slim down dependencies
workqueue: Split out workqueue_types.h
...
Pull MM updates from Andrew Morton:
"Many singleton patches against the MM code. The patch series which are
included in this merge do the following:
- Peng Zhang has done some mapletree maintainance work in the series
'maple_tree: add mt_free_one() and mt_attr() helpers'
'Some cleanups of maple tree'
- In the series 'mm: use memmap_on_memory semantics for dax/kmem'
Vishal Verma has altered the interworking between memory-hotplug
and dax/kmem so that newly added 'device memory' can more easily
have its memmap placed within that newly added memory.
- Matthew Wilcox continues folio-related work (including a few fixes)
in the patch series
'Add folio_zero_tail() and folio_fill_tail()'
'Make folio_start_writeback return void'
'Fix fault handler's handling of poisoned tail pages'
'Convert aops->error_remove_page to ->error_remove_folio'
'Finish two folio conversions'
'More swap folio conversions'
- Kefeng Wang has also contributed folio-related work in the series
'mm: cleanup and use more folio in page fault'
- Jim Cromie has improved the kmemleak reporting output in the series
'tweak kmemleak report format'.
- In the series 'stackdepot: allow evicting stack traces' Andrey
Konovalov to permits clients (in this case KASAN) to cause eviction
of no longer needed stack traces.
- Charan Teja Kalla has fixed some accounting issues in the page
allocator's atomic reserve calculations in the series 'mm:
page_alloc: fixes for high atomic reserve caluculations'.
- Dmitry Rokosov has added to the samples/ dorectory some sample code
for a userspace memcg event listener application. See the series
'samples: introduce cgroup events listeners'.
- Some mapletree maintanance work from Liam Howlett in the series
'maple_tree: iterator state changes'.
- Nhat Pham has improved zswap's approach to writeback in the series
'workload-specific and memory pressure-driven zswap writeback'.
- DAMON/DAMOS feature and maintenance work from SeongJae Park in the
series
'mm/damon: let users feed and tame/auto-tune DAMOS'
'selftests/damon: add Python-written DAMON functionality tests'
'mm/damon: misc updates for 6.8'
- Yosry Ahmed has improved memcg's stats flushing in the series 'mm:
memcg: subtree stats flushing and thresholds'.
- In the series 'Multi-size THP for anonymous memory' Ryan Roberts
has added a runtime opt-in feature to transparent hugepages which
improves performance by allocating larger chunks of memory during
anonymous page faults.
- Matthew Wilcox has also contributed some cleanup and maintenance
work against eh buffer_head code int he series 'More buffer_head
cleanups'.
- Suren Baghdasaryan has done work on Andrea Arcangeli's series
'userfaultfd move option'. UFFDIO_MOVE permits userspace heap
compaction algorithms to move userspace's pages around rather than
UFFDIO_COPY'a alloc/copy/free.
- Stefan Roesch has developed a 'KSM Advisor', in the series 'mm/ksm:
Add ksm advisor'. This is a governor which tunes KSM's scanning
aggressiveness in response to userspace's current needs.
- Chengming Zhou has optimized zswap's temporary working memory use
in the series 'mm/zswap: dstmem reuse optimizations and cleanups'.
- Matthew Wilcox has performed some maintenance work on the writeback
code, both code and within filesystems. The series is 'Clean up the
writeback paths'.
- Andrey Konovalov has optimized KASAN's handling of alloc and free
stack traces for secondary-level allocators, in the series 'kasan:
save mempool stack traces'.
- Andrey also performed some KASAN maintenance work in the series
'kasan: assorted clean-ups'.
- David Hildenbrand has gone to town on the rmap code. Cleanups, more
pte batching, folio conversions and more. See the series 'mm/rmap:
interface overhaul'.
- Kinsey Ho has contributed some maintenance work on the MGLRU code
in the series 'mm/mglru: Kconfig cleanup'.
- Matthew Wilcox has contributed lruvec page accounting code cleanups
in the series 'Remove some lruvec page accounting functions'"
* tag 'mm-stable-2024-01-08-15-31' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (361 commits)
mm, treewide: rename MAX_ORDER to MAX_PAGE_ORDER
mm, treewide: introduce NR_PAGE_ORDERS
selftests/mm: add separate UFFDIO_MOVE test for PMD splitting
selftests/mm: skip test if application doesn't has root privileges
selftests/mm: conform test to TAP format output
selftests: mm: hugepage-mmap: conform to TAP format output
selftests/mm: gup_test: conform test to TAP format output
mm/selftests: hugepage-mremap: conform test to TAP format output
mm/vmstat: move pgdemote_* out of CONFIG_NUMA_BALANCING
mm: zsmalloc: return -ENOSPC rather than -EINVAL in zs_malloc while size is too large
mm/memcontrol: remove __mod_lruvec_page_state()
mm/khugepaged: use a folio more in collapse_file()
slub: use a folio in __kmalloc_large_node
slub: use folio APIs in free_large_kmalloc()
slub: use alloc_pages_node() in alloc_slab_page()
mm: remove inc/dec lruvec page state functions
mm: ratelimit stat flush from workingset shrinker
kasan: stop leaking stack trace handles
mm/mglru: remove CONFIG_TRANSPARENT_HUGEPAGE
mm/mglru: add dummy pmd_dirty()
...
Pull performance events updates from Ingo Molnar:
- Add branch stack counters ABI extension to better capture the growing
amount of information the PMU exposes via branch stack sampling.
There's matching tooling support.
- Fix race when creating the nr_addr_filters sysfs file
- Add Intel Sierra Forest and Grand Ridge intel/cstate PMU support
- Add Intel Granite Rapids, Sierra Forest and Grand Ridge uncore PMU
support
- Misc cleanups & fixes
* tag 'perf-core-2024-01-08' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/x86/intel/uncore: Factor out topology_gidnid_map()
perf/x86/intel/uncore: Fix NULL pointer dereference issue in upi_fill_topology()
perf/x86/amd: Reject branch stack for IBS events
perf/x86/intel/uncore: Support Sierra Forest and Grand Ridge
perf/x86/intel/uncore: Support IIO free-running counters on GNR
perf/x86/intel/uncore: Support Granite Rapids
perf/x86/uncore: Use u64 to replace unsigned for the uncore offsets array
perf/x86/intel/uncore: Generic uncore_get_uncores and MMIO format of SPR
perf: Fix the nr_addr_filters fix
perf/x86/intel/cstate: Add Grand Ridge support
perf/x86/intel/cstate: Add Sierra Forest support
x86/smp: Export symbol cpu_clustergroup_mask()
perf/x86/intel/cstate: Cleanup duplicate attr_groups
perf/core: Fix narrow startup race when creating the perf nr_addr_filters sysfs file
perf/x86/intel: Support branch counters logging
perf/x86/intel: Reorganize attrs and is_visible
perf: Add branch_sample_call_stack
perf/x86: Add PERF_X86_EVENT_NEEDS_BRANCH_STACK flag
perf: Add branch stack counters
Pull x86 core updates from Ingo Molnar:
- Add comments about the magic behind the shadow STI
before MWAIT in __sti_mwait().
- Fix possible unintended timer delays caused by a race
in mwait_idle_with_hints().
* tag 'x86-core-2024-01-08' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86: Fix CPUIDLE_FLAG_IRQ_ENABLE leaking timer reprogram
x86: Add a comment about the "magic" behind shadow sti before mwait
Pull x86 cleanups from Ingo Molnar:
- Change global variables to local
- Add missing kernel-doc function parameter descriptions
- Remove unused parameter from a macro
- Remove obsolete Kconfig entry
- Fix comments
- Fix typos, mostly scripted, manually reviewed
and a micro-optimization got misplaced as a cleanup:
- Micro-optimize the asm code in secondary_startup_64_no_verify()
* tag 'x86-cleanups-2024-01-08' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
arch/x86: Fix typos
x86/head_64: Use TESTB instead of TESTL in secondary_startup_64_no_verify()
x86/docs: Remove reference to syscall trampoline in PTI
x86/Kconfig: Remove obsolete config X86_32_SMP
x86/io: Remove the unused 'bw' parameter from the BUILDIO() macro
x86/mtrr: Document missing function parameters in kernel-doc
x86/setup: Make relocated_ramdisk a local variable of relocate_initrd()
Pull x86 asm updates from Ingo Molnar:
"Replace magic numbers in GDT descriptor definitions & handling:
- Introduce symbolic names via macros for descriptor
types/fields/flags, and then use these symbolic names.
- Clean up definitions a bit, such as GDT_ENTRY_INIT()
- Fix/clean up details that became visibly inconsistent after the
symbol-based code was introduced:
- Unify accessed flag handling
- Set the D/B size flag consistently & according to the HW
specification"
* tag 'x86-asm-2024-01-08' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/asm: Add DB flag to 32-bit percpu GDT entry
x86/asm: Always set A (accessed) flag in GDT descriptors
x86/asm: Replace magic numbers in GDT descriptors, script-generated change
x86/asm: Replace magic numbers in GDT descriptors, preparations
x86/asm: Provide new infrastructure for GDT descriptors
Pull x86 apic updates from Ingo Molnar:
- Clean up 'struct apic':
- Drop ::delivery_mode
- Drop 'enum apic_delivery_modes'
- Drop 'struct local_apic'
- Fix comments
* tag 'x86-apic-2024-01-08' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/ioapic: Remove unfinished sentence from comment
x86/apic: Drop struct local_apic
x86/apic: Drop enum apic_delivery_modes
x86/apic: Drop apic::delivery_mode
Pull x86 RAS updates from Borislav Petkov:
- Convert the hw error storm handling into a finer-grained, per-bank
solution which allows for more timely detection and reporting of
errors
- Start a documentation section which will hold down relevant RAS
features description and how they should be used
- Add new AMD error bank types
- Slim down and remove error type descriptions from the kernel side of
error decoding to rasdaemon which can be used from now on to decode
hw errors on AMD
- Mark pages containing uncorrectable errors as poison so that kdump
can avoid them and thus not cause another panic
- The usual cleanups and fixlets
* tag 'ras_core_for_v6.8' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/mce: Handle Intel threshold interrupt storms
x86/mce: Add per-bank CMCI storm mitigation
x86/mce: Remove old CMCI storm mitigation code
Documentation: Begin a RAS section
x86/MCE/AMD: Add new MA_LLC, USR_DP, and USR_CP bank types
EDAC/mce_amd: Remove SMCA Extended Error code descriptions
x86/mce/amd, EDAC/mce_amd: Move long names to decoder module
x86/mce/inject: Clear test status value
x86/mce: Remove redundant check from mce_device_create()
x86/mce: Mark fatal MCE's page as poison to avoid panic in the kdump kernel
Pull x86 cpu feature updates from Borislav Petkov:
- Add synthetic X86_FEATURE flags for the different AMD Zen generations
and use them everywhere instead of ad-hoc family/model checks. Drop
an ancient AMD errata checking facility as a result
- Fix a fragile initcall ordering in intel_epb
- Do not issue the MFENCE+LFENCE barrier for the TSC deadline and
X2APIC MSRs on AMD as it is not needed there
* tag 'x86_cpu_for_v6.8' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/CPU/AMD: Add X86_FEATURE_ZEN1
x86/CPU/AMD: Drop now unused CPU erratum checking function
x86/CPU/AMD: Get rid of amd_erratum_1485[]
x86/CPU/AMD: Get rid of amd_erratum_400[]
x86/CPU/AMD: Get rid of amd_erratum_383[]
x86/CPU/AMD: Get rid of amd_erratum_1054[]
x86/CPU/AMD: Move the DIV0 bug detection to the Zen1 init function
x86/CPU/AMD: Move Zenbleed check to the Zen2 init function
x86/CPU/AMD: Rename init_amd_zn() to init_amd_zen_common()
x86/CPU/AMD: Call the spectral chicken in the Zen2 init function
x86/CPU/AMD: Move erratum 1076 fix into the Zen1 init function
x86/CPU/AMD: Move the Zen3 BTC_NO detection to the Zen3 init function
x86/CPU/AMD: Carve out the erratum 1386 fix
x86/CPU/AMD: Add ZenX generations flags
x86/cpu/intel_epb: Don't rely on link order
x86/barrier: Do not serialize MSR accesses on AMD
Pull x86 paravirt updates from Borislav Petkov:
- Replace the paravirt patching functionality using the alternatives
infrastructure and remove the former
- Misc other improvements
* tag 'x86_paravirt_for_v6.8' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/alternative: Correct feature bit debug output
x86/paravirt: Remove no longer needed paravirt patching code
x86/paravirt: Switch mixed paravirt/alternative calls to alternatives
x86/alternative: Add indirect call patching
x86/paravirt: Move some functions and defines to alternative.c
x86/paravirt: Introduce ALT_NOT_XEN
x86/paravirt: Make the struct paravirt_patch_site packed
x86/paravirt: Use relative reference for the original instruction offset
Pull misc x86 updates from Borislav Petkov:
- Add an informational message which gets issued when IA32 emulation
has been disabled on the cmdline
- Clarify in detail how /proc/cpuinfo is used on x86
- Fix a theoretical overflow in num_digits()
* tag 'x86_misc_for_v6.8' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/ia32: State that IA32 emulation is disabled
Documentation/x86: Document what /proc/cpuinfo is for
x86/lib: Fix overflow when counting digits
KVM x86 MMU changes for 6.8:
- Fix a relatively benign off-by-one error when splitting huge pages during
CLEAR_DIRTY_LOG.
- Fix a bug where KVM could incorrectly test-and-clear dirty bits in non-leaf
TDP MMU SPTEs if a racing thread replaces a huge SPTE with a non-huge SPTE.
- Relax the TDP MMU's lockdep assertions related to holding mmu_lock for read
versus write so that KVM doesn't pass "bool shared" all over the place just
to have precise assertions in paths that don't actually care about whether
the caller is a reader or a writer.
KVM x86 support for virtualizing Linear Address Masking (LAM)
Add KVM support for Linear Address Masking (LAM). LAM tweaks the canonicality
checks for most virtual address usage in 64-bit mode, such that only the most
significant bit of the untranslated address bits must match the polarity of the
last translated address bit. This allows software to use ignored, untranslated
address bits for metadata, e.g. to efficiently tag pointers for address
sanitization.
LAM can be enabled separately for user pointers and supervisor pointers, and
for userspace LAM can be select between 48-bit and 57-bit masking
- 48-bit LAM: metadata bits 62:48, i.e. LAM width of 15.
- 57-bit LAM: metadata bits 62:57, i.e. LAM width of 6.
For user pointers, LAM enabling utilizes two previously-reserved high bits from
CR3 (similar to how PCID_NOFLUSH uses bit 63): LAM_U48 and LAM_U57, bits 62 and
61 respectively. Note, if LAM_57 is set, LAM_U48 is ignored, i.e.:
- CR3.LAM_U48=0 && CR3.LAM_U57=0 == LAM disabled for user pointers
- CR3.LAM_U48=1 && CR3.LAM_U57=0 == LAM-48 enabled for user pointers
- CR3.LAM_U48=x && CR3.LAM_U57=1 == LAM-57 enabled for user pointers
For supervisor pointers, LAM is controlled by a single bit, CR4.LAM_SUP, with
the 48-bit versus 57-bit LAM behavior following the current paging mode, i.e.:
- CR4.LAM_SUP=0 && CR4.LA57=x == LAM disabled for supervisor pointers
- CR4.LAM_SUP=1 && CR4.LA57=0 == LAM-48 enabled for supervisor pointers
- CR4.LAM_SUP=1 && CR4.LA57=1 == LAM-57 enabled for supervisor pointers
The modified LAM canonicality checks:
- LAM_S48 : [ 1 ][ metadata ][ 1 ]
63 47
- LAM_U48 : [ 0 ][ metadata ][ 0 ]
63 47
- LAM_S57 : [ 1 ][ metadata ][ 1 ]
63 56
- LAM_U57 + 5-lvl paging : [ 0 ][ metadata ][ 0 ]
63 56
- LAM_U57 + 4-lvl paging : [ 0 ][ metadata ][ 0...0 ]
63 56..47
The bulk of KVM support for LAM is to emulate LAM's modified canonicality
checks. The approach taken by KVM is to "fill" the metadata bits using the
highest bit of the translated address, e.g. for LAM-48, bit 47 is sign-extended
to bits 62:48. The most significant bit, 63, is *not* modified, i.e. its value
from the raw, untagged virtual address is kept for the canonicality check. This
untagging allows
Aside from emulating LAM's canonical checks behavior, LAM has the usual KVM
touchpoints for selectable features: enumeration (CPUID.7.1:EAX.LAM[bit 26],
enabling via CR3 and CR4 bits, etc.
KVM x86 PMU changes for 6.8:
- Fix a variety of bugs where KVM fail to stop/reset counters and other state
prior to refreshing the vPMU model.
- Fix a double-overflow PMU bug by tracking emulated counter events using a
dedicated field instead of snapshotting the "previous" counter. If the
hardware PMC count triggers overflow that is recognized in the same VM-Exit
that KVM manually bumps an event count, KVM would pend PMIs for both the
hardware-triggered overflow and for KVM-triggered overflow.
KVM x86 Hyper-V changes for 6.8:
- Guard KVM-on-HyperV's range-based TLB flush hooks with an #ifdef on
CONFIG_HYPERV as a minor optimization, and to self-document the code.
- Add CONFIG_KVM_HYPERV to allow disabling KVM support for HyperV "emulation"
at build time.
KVM/riscv changes for 6.8 part #1
- KVM_GET_REG_LIST improvement for vector registers
- Generate ISA extension reg_list using macros in get-reg-list selftest
- Steal time account support along with selftest
Only the posix timer system calls use this (when the posix timer support
is disabled, which does not actually happen in any normal case), because
they had debug code to print out a warning about missing system calls.
Get rid of that special case, and just use the standard COND_SYSCALL
interface that creates weak system call stubs that return -ENOSYS for
when the system call does not exist.
This fixes a kCFI issue with the SYS_NI() hackery:
CFI failure at int80_emulation+0x67/0xb0 (target: sys_ni_posix_timers+0x0/0x70; expected type: 0xb02b34d9)
WARNING: CPU: 0 PID: 48 at int80_emulation+0x67/0xb0
Reported-by: kernel test robot <oliver.sang@intel.com>
Reviewed-by: Sami Tolvanen <samitolvanen@google.com>
Tested-by: Sami Tolvanen <samitolvanen@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Borislav Petkov <bp@alien8.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We'd like to replace all the magic numbers in various GDT descriptors
with new, semantically meaningful, symbolic values.
In order to be able to verify that the change doesn't cause any actual
changes to the compiled binary code, I've split the change into two
patches:
- Part 1 (this commit): everything _but_ actually replacing the numbers
- Part 2 (the following commit): _only_ replacing the numbers
The reason we need this split for verification is that including new
headers causes some spurious changes to the object files, mostly line
number changes in the debug info but occasionally other subtle codegen
changes.
Signed-off-by: Vegard Nossum <vegard.nossum@oracle.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Link: https://lore.kernel.org/r/20231219151200.2878271-3-vegard.nossum@oracle.com
Linus suggested replacing the magic numbers in the GDT descriptors
using preprocessor macros. Designing the interface properly is actually
pretty hard -- there are several constraints:
- you want the final expressions to be readable at a glance; something
like GDT_ENTRY_FLAGS(5, 1, 0, 1, 0, 1, 1, 0) isn't because you need
to visit the definition to understand what each parameter represents
and then match up parameters in the user and the definition (which is
hard when there are so many of them)
- you want the final expressions to be fairly short/information-dense;
something like GDT_ENTRY_PRESENT | GDT_ENTRY_DATA_WRITABLE |
GDT_ENTRY_SYSTEM | GDT_ENTRY_DB | GDT_ENTRY_GRANULARITY_4K is a bit
too verbose to write out every time and is actually hard to read as
well because of all the repetition
- you may want to assume defaults for some things (e.g. entries are
DPL-0 a.k.a. kernel segments by default) and allow the user to
override the default -- but this works best if you can OR in the
override; if you want DPL-3 by default and override with DPL-0 you
would need to start masking off bits instead of OR-ing them in and
that just becomes harder to read
- you may want to parameterize some things (e.g. CODE vs. DATA or
KERNEL vs. USER) since both values are used and you don't really
want prefer either one by default -- or DPL, which is always some
value that is always specified
This patch tries to balance these requirements and has two layers of
definitions -- low-level and high-level:
- the low-level defines are the mapping between human-readable names
and the actual bit numbers
- the high-level defines are the mapping from high-level intent to
combinations of low-level flags, representing roughly a tuple
(data/code/tss, 64/32/16-bits) plus an override for DPL-3 (= USER),
since that's relatively rare but still very important to mark
properly for those segments.
- we have *_BIOS variants for 32-bit code and data segments that don't
have the G flag set and give the limit in terms of bytes instead of
pages
[ mingo: Improved readability bit more. ]
Signed-off-by: Vegard Nossum <vegard.nossum@oracle.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Link: https://lore.kernel.org/r/20231219151200.2878271-2-vegard.nossum@oracle.com
Alexei Starovoitov says:
====================
pull-request: bpf-next 2023-12-18
This PR is larger than usual and contains changes in various parts
of the kernel.
The main changes are:
1) Fix kCFI bugs in BPF, from Peter Zijlstra.
End result: all forms of indirect calls from BPF into kernel
and from kernel into BPF work with CFI enabled. This allows BPF
to work with CONFIG_FINEIBT=y.
2) Introduce BPF token object, from Andrii Nakryiko.
It adds an ability to delegate a subset of BPF features from privileged
daemon (e.g., systemd) through special mount options for userns-bound
BPF FS to a trusted unprivileged application. The design accommodates
suggestions from Christian Brauner and Paul Moore.
Example:
$ sudo mkdir -p /sys/fs/bpf/token
$ sudo mount -t bpf bpffs /sys/fs/bpf/token \
-o delegate_cmds=prog_load:MAP_CREATE \
-o delegate_progs=kprobe \
-o delegate_attachs=xdp
3) Various verifier improvements and fixes, from Andrii Nakryiko, Andrei Matei.
- Complete precision tracking support for register spills
- Fix verification of possibly-zero-sized stack accesses
- Fix access to uninit stack slots
- Track aligned STACK_ZERO cases as imprecise spilled registers.
It improves the verifier "instructions processed" metric from single
digit to 50-60% for some programs.
- Fix verifier retval logic
4) Support for VLAN tag in XDP hints, from Larysa Zaremba.
5) Allocate BPF trampoline via bpf_prog_pack mechanism, from Song Liu.
End result: better memory utilization and lower I$ miss for calls to BPF
via BPF trampoline.
6) Fix race between BPF prog accessing inner map and parallel delete,
from Hou Tao.
7) Add bpf_xdp_get_xfrm_state() kfunc, from Daniel Xu.
It allows BPF interact with IPSEC infra. The intent is to support
software RSS (via XDP) for the upcoming ipsec pcpu work.
Experiments on AWS demonstrate single tunnel pcpu ipsec reaching
line rate on 100G ENA nics.
8) Expand bpf_cgrp_storage to support cgroup1 non-attach, from Yafang Shao.
9) BPF file verification via fsverity, from Song Liu.
It allows BPF progs get fsverity digest.
* tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (164 commits)
bpf: Ensure precise is reset to false in __mark_reg_const_zero()
selftests/bpf: Add more uprobe multi fail tests
bpf: Fail uprobe multi link with negative offset
selftests/bpf: Test the release of map btf
s390/bpf: Fix indirect trampoline generation
selftests/bpf: Temporarily disable dummy_struct_ops test on s390
x86/cfi,bpf: Fix bpf_exception_cb() signature
bpf: Fix dtor CFI
cfi: Add CFI_NOSEAL()
x86/cfi,bpf: Fix bpf_struct_ops CFI
x86/cfi,bpf: Fix bpf_callback_t CFI
x86/cfi,bpf: Fix BPF JIT call
cfi: Flip headers
selftests/bpf: Add test for abnormal cnt during multi-kprobe attachment
selftests/bpf: Don't use libbpf_get_error() in kprobe_multi_test
selftests/bpf: Add test for abnormal cnt during multi-uprobe attachment
bpf: Limit the number of kprobes when attaching program to multiple kprobes
bpf: Limit the number of uprobes when attaching program to multiple uprobes
bpf: xdp: Register generic_kfunc_set with XDP programs
selftests/bpf: utilize string values for delegate_xxx mount options
...
====================
Link: https://lore.kernel.org/r/20231219000520.34178-1-alexei.starovoitov@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
