Pull x86 fix from Borislav Petkov:
- Add a proper kernel cmdline option to control the TLB invalidation
method on x86 prompted mainly by a recent finding on AMD related to
INVLPGB/TYLBSYNC invalidations.
Having the command line option is simply another way to alleviate
the situation short-term
* tag 'x86_urgent_for_v7.2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/CPU: Add a tlbi= cmdline switch
Pull SoC fixes from Arnd Bergmann:
"These are three last-minute fixes for the 7.2 release, though nothing
alarming:
- one error handling fix for optee firmware
- incorrect i2c data for the apple M3 that was added in 7.2
- a boot time warning fix for nvidia tegra"
* tag 'soc-fixes-7.2-3' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc:
arm64: tegra: Add EL2 virtual timer interrupt for Tegra194
arm64: dts: apple: t8122: Fix I2C resources
optee: ffa: Add NULL check in optee_ffa_lend_protmem
Pull OpenRISC fix from Stafford Horne:
"A bug fix found by researchers:
- mask all privileged bits when restoring the supervisor register
from sigreturn"
* tag 'for-linus' of https://github.com/openrisc/linux:
openrisc: signal: do not restore privileged SR bits on sigreturn
restore_sigcontext() copies the whole supervision register (SR) from the
signal frame and only clears SPR_SR_SM before the value is reloaded into
the hardware SR (through ESR and l.rfe) on the return to user space. All
other SR bits are left under user control.
An unprivileged task can thus return from a signal handler through a
crafted sigframe that clears SPR_SR_DME. With the data MMU disabled the
CPU performs no translation or protection on data accesses, so the task
gains read and write access to arbitrary physical memory, a local
privilege escalation. SPR_SR_IME, SPR_SR_SUMRA, SPR_SR_LEE, SPR_SR_EPH
and the cache-enable bits are exposed the same way. The ptrace GPR regset
already refuses any change to SR for exactly this reason.
Restore only the arithmetic flag bits (F, CY, OV) from the signal frame
and take every privileged control bit from the SR the kernel saved on
signal entry.
Verified with qemu-system-or1k -M or1k-sim: before this change an
unprivileged PoC clears SPR_SR_DME in rt_sigreturn and writes a marker to
physical address 0x03000000 (beyond the kernel's mem=32M); afterwards the
same PoC receives SIGSEGV and physical memory is unchanged.
Fixes: ac689eb7f9 ("OpenRISC: Signal handling")
Cc: stable@vger.kernel.org
Signed-off-by: Ali Ahmet Memis <ali@iusegentoo.com>
Signed-off-by: Stafford Horne <shorne@gmail.com>
Pull RISC-V fixes from Paul Walmsley:
- Fix a fault caused when the RISC-V Zbb-enabled strlen() is executed
on a string that ends right before a page boundary, when the next
page is unmapped
- Fix a race with the misaligned vector performance testing code that
can prevent the outcome of the test from being stored into the vDSO
cache
- Fix a kernel warning generated by the ftrace code when
ftrace_modify_call_code() runs against a ftrace-traced function where
a kprobe has already been attached. This shows up in the bpf
kselftests
* tag 'riscv-for-linus-v7.2-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux:
riscv: lib: Fix ZBB strnlen reading past count boundary
riscv: hwprobe: Register unaligned probes before usermode
riscv: ftrace: Fix ftrace_modify_call failure on kprobed functions
Pull m68k fix from Geert Uytterhoeven:
"Define NR_CPUS to 1.
This fixes a long-standing but never critical before oddity on m68k,
that turned into a serious configuration issue after a recent erofs
change"
* tag 'm68k-for-v7.2-tag2' of git://git.kernel.org/pub/scm/linux/kernel/git/geert/linux-m68k:
m68k: Define NR_CPUS to 1
This fixes a Kconfig warning
fs/erofs/Kconfig:137:warning: range is invalid
which originates from EROFS_FS_ZIP_LZMA_DEFAULT_MAX_STREAMS using
NR_CPUS which up to now didn't exist for ARCH=m68k. All other
architectures define this symbol, so fix the outlier.
[geert] This also fixes:
- CONFIG_EROFS_FS_ZIP_LZMA_DEFAULT_MAX_STREAMS being set to the
literal NR_CPUS instead of a number by automatic configs like
"make allmodconfig" or "make olddefconfig",
- An infinite loop in manual configs like "make oldconfig" when
CONFIG_EROFS_FS_ZIP_LZMA_DEFAULT_MAX_STREAMS is not present or
has an invalid value in your existing .config.
Fixes: c9b47e6b23 ("erofs: cap LZMA stream pool size")
Signed-off-by: Uwe Kleine-König <ukleinek@kernel.org>
Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Link: https://patch.msgid.link/20260731094950.1988084-2-ukleinek@kernel.org
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
With the recently found INVLPGB / TLBSYNC issue, there has been some
interest in disabling INVLPGB-based TLB flushing, in order to rule out
that CPU issue as a cause of userspace crashes.
Add a kernel command line option to control the TLB flushing behavior.
If the need arises, we will add a "tlbi=broadcast" for the case when TLB
invalidation broadcasts need to be explicitly selected, but this is not
needed now yet.
[ bp: Rewrite commit message, move to cpu/common.c, add documentation. ]
Fixes: 767ae437a3 ("x86/mm: Add INVLPGB feature and Kconfig entry")
Suggested-by: Borislav Petkov <bp@alien8.de>
Signed-off-by: Rik van Riel <riel@surriel.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Cc: <stable@kernel.org>
Link: https://patch.msgid.link/20260729204341.3eb0b5ea@fangorn
arm64: tegra: Device tree fixes for v7.2
This contains a single fix adding an interrupt to the architected
timer's device tree node for the EL2 virtual timer. This prevents
a warning from the driver at boot time.
* tag 'tegra-for-7.2-arm64-dt-fixes-v2' of git://git.kernel.org/pub/scm/linux/kernel/git/tegra/linux:
arm64: tegra: Add EL2 virtual timer interrupt for Tegra194
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Pull x86 fix from Ingo Molnar:
- Fix MCE CMCI discovery initialization ordering bug (Breno Leitao)
* tag 'x86-urgent-2026-08-08' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/mce: Set up the polling timer before CMCI discovery
The ZBB-optimized strnlen loop loads one word ahead before checking the
aligned boundary:
REG_L t1, SZREG(t0) // load next word
addi t0, t0, SZREG // advance
orc.b t1, t1
bgeu t0, t4, 4f // boundary check AFTER load
where t4 = (s + count) & -SZREG. When s is aligned and count is a
multiple of SZREG, t4 equals s + count and the loop loads a full word
starting at exactly s + count. If s + count falls on a page boundary
with the next page unmapped, this faults.
Fix by computing the aligned boundary from the last valid byte
(s + count - 1) instead of s + count. This makes the loop stop at the
word containing the last valid byte rather than potentially loading the
word after it. The count == 0 case is already handled by the beqz
early exit.
Also add a pre-loop guard (bgeu t0, t4) for the case where all valid
bytes fit within the first word. With the adjusted boundary, t4 can
equal t0, and entering the loop with stale register state from the
first-word processing would produce incorrect results.
The final minu clamp ensures the result is still correct when the last
loaded word extends past s + count - 1 within the same aligned word.
Fixes: 5ba15d419f ("riscv: lib: add strnlen() implementation")
Signed-off-by: Michael Neuling <mikey@neuling.org>
Assisted-by: Claude Opus4.6 High Thinking
Link: https://patch.msgid.link/20260413010738.1622423-1-mikey@neuling.org
Signed-off-by: Paul Walmsley <pjw@kernel.org>
Pull powerpc fixes from Madhavan Srinivasan:
- A couple of fixes for a memory leak and a underflow case
Thanks to George Wilson and R Nageswara Sastry
* tag 'powerpc-7.2-4' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
powerpc/pseries: lparcfg - fix kbuf[] underflow
powerpc/pseries: pci - logic bug
powerpc/pseries: papr-phy-attest - validate cmd.length, plug mem leak
In lparcfg_write(), a count of 0 results in kbuf[] being indexed at -1.
Check for count == 0 in the existing check for count > sizeof(kbuf) and
return -EINVAL if true.
Fixes: 74422e2b19 ("powerpc/pseries: Remove VLA from lparcfg_write()")
Acked-by: Nayna Jain <nayna@linux.ibm.com>
Tested-by: R Nageswara Sastry <rnsastry@linux.ibm.com>
Cc: stable@vger.kernel.org # 4.20
Signed-off-by: George Wilson <gcwilson@linux.ibm.com>
Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com>
In papr_phy_attest_create_handle(), the params->cmd.length is not
validated before use, which can result in a buffer overlow. Check it and
return -EINVAL if it is either 0 or exceeds sizeof(params->cmd).
Also, params is freed on the success path but not error. Free it on
errors after memory allocation. And free it on negative fd.
Fixes: 86900ab620 ("powerpc/pseries: Add a char driver for physical-attestation RTAS")
Acked-by: Haren Myneni <haren@linux.ibm.com>
Acked-by: Nayna Jain <nayna@linux.ibm.com>
Tested-by: R Nageswara Sastry <rnsastry@linux.ibm.com>
Cc: stable@vger.kernel.org # 6.16
Signed-off-by: George Wilson <gcwilson@linux.ibm.com>
Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com>
The hwprobe vDSO data is populated by the first riscv_hwprobe syscall.
Some values, such as MISALIGNED_VECTOR_PERF, may depend on the async
vector unaligned access speed probe registered by
check_unaligned_access_all_cpus().
That initcall currently runs at late_initcall level. However,
rootfs_initcall enables usermode helpers before late initcalls run, so an
early helper can execute userspace and call riscv_hwprobe first.
In that case complete_hwprobe_vdso_data() consumes the initial
pending_boot_probes reference, populates the vDSO cache, and marks it
ready before the later async probe is registered. The eventual probe
result then cannot update the already-ready cache.
Move check_unaligned_access_all_cpus() to fs_initcall_sync. This still
runs after clocksource_done_booting(), so the ktime_get_mono_fast_ns()
benchmark uses a stable clocksource, but it runs before rootfs_initcall
enables usermode helpers.
Any async hwprobe probe is therefore registered before userspace can
trigger the one-time vDSO cache population.
Cc: stable@vger.kernel.org
Fixes: 6455c6c118 ("riscv: Clean up & optimize unaligned scalar access probe")
Signed-off-by: Rui Qi <qirui.001@bytedance.com>
Reviewed-by: Nam Cao <namcao@linutronix.de>
Link: https://patch.msgid.link/20260721150511.1607105-1-qirui.001@bytedance.com
Signed-off-by: Paul Walmsley <pjw@kernel.org>
Pull vkm fixes from Paolo Bonzini:
"s390:
- fix a lot of small bugs and races
x86:
- fix missing locking related to KVM_CAP_MOVE_ENC_CONTEXT_FROM
- warn on creating a new page table that is the child of an invalid
one, and limit damage before it's too late
- disable use of INVLPGA when NPT is enabled, because it doesn't seem
to flush TLBs correctly"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (26 commits)
KVM: x86/mmu: WARN and clear role.invalid when creating a child shadow page
KVM: SVM: Serialize accesses to the owner and mirror list with separate lock
KVM: SVM: make svm_flush_tlb_gva do a full asid flush if NPT enabled
KVM: s390: Fix cleanup in kvm_s390_pv_create_cpu()
KVM: s390: Fix ordering when adding to SCA
KVM: s390: Return -EINTR if a signal is pending while faulting-in
KVM: s390: Free the mmu cache when kvm_arch_vcpu_create() fails
KVM: s390: ucontrol: Add missing locking around gmap_remove_child()
KVM: s390: cmma: Fix dirty tracking when removing memslot
KVM: s390: Fix race in __do_essa()
KVM: s390: Fix leaking of PGM_ADDRESSING to userspace
KVM: s390: ucontrol: Fix sca_clear_ext_call()
KVM: s390: Fix overclearing ESCA in case of error
KVM: s390: Fix kvm_s390_vcpu_unsetup_cmma()
KVM: s390: Do not free SCA if it was not allocated
KVM: s390: Fix unlikely NULL gmap dereference
s390/vfio_ccw: Implement a crw lock
s390/vfio_ccw: Selectively expand io_mutex
s390/vfio_ccw: Move cp cleanup out of not operational
s390/vfio_ccw: Cancel existing workqueues
...
Explicitly clear role.invalid when deriving a child shadow page's role from
its parent to harden against bugs elsewhere in KVM, as violating KVM's
invariant that invalid pages are NOT on the list of active MMU pages leads
to use-after-free due to __kvm_mmu_prepare_zap_page() using list_add()
instead of list_move() when processing an invalid shadow page, i.e. makes a
bad situation far worse.
Yell loudly if the parent is invalid, as it means KVM has missed a validity
check, i.e. KVM is attempting to map memory using an invalid/obsolete root,
but continue on as the child is otherwise still a valid shadow page.
==================================================================
BUG: KASAN: slab-use-after-free in __kvm_mmu_get_shadow_page+0x1817/0x1860 [kvm]
Write of size 8 at addr ff11000153dd1368 by task repro/853
CPU: 1 UID: 1000 PID: 853 Comm: repro Not tainted 7.2.0-rc2-3aec122bdcaf-next-vm #5 PREEMPT
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015
Call Trace:
<TASK>
dump_stack_lvl+0x4b/0x70
print_report+0x153/0x49c
kasan_report+0xbc/0xf0
__kvm_mmu_get_shadow_page+0x1817/0x1860 [kvm]
mmu_alloc_root+0x141/0x320 [kvm]
kvm_mmu_load+0x612/0x20f0 [kvm]
kvm_arch_vcpu_ioctl_run+0x3dd5/0x6150 [kvm]
kvm_vcpu_ioctl+0x5e4/0x10d0 [kvm]
__x64_sys_ioctl+0x131/0x1b0
do_syscall_64+0x67/0x5f0
entry_SYSCALL_64_after_hwframe+0x4b/0x53
</TASK>
Allocated by task 853:
kasan_save_stack+0x20/0x40
kasan_save_track+0x14/0x30
__kasan_slab_alloc+0x5f/0x70
kmem_cache_alloc_noprof+0xfe/0x2e0
__kvm_mmu_topup_memory_cache+0x135/0x530 [kvm]
paging64_page_fault+0x318/0x1e30 [kvm]
kvm_mmu_do_page_fault+0x21d/0x630 [kvm]
kvm_mmu_page_fault+0x18c/0x17b0 [kvm]
kvm_arch_vcpu_ioctl_run+0x1f35/0x6150 [kvm]
kvm_vcpu_ioctl+0x5e4/0x10d0 [kvm]
__x64_sys_ioctl+0x131/0x1b0
do_syscall_64+0x67/0x5f0
entry_SYSCALL_64_after_hwframe+0x4b/0x53
Freed by task 853:
kasan_save_stack+0x20/0x40
kasan_save_track+0x14/0x30
kasan_save_free_info+0x3b/0x60
__kasan_slab_free+0x43/0x70
kmem_cache_free+0xe2/0x400
kvm_mmu_commit_zap_page.part.0+0x1e2/0x310 [kvm]
kvm_mmu_free_roots+0x283/0x560 [kvm]
kvm_arch_vcpu_ioctl_run+0x33c8/0x6150 [kvm]
kvm_vcpu_ioctl+0x5e4/0x10d0 [kvm]
__x64_sys_ioctl+0x131/0x1b0
do_syscall_64+0x67/0x5f0
entry_SYSCALL_64_after_hwframe+0x4b/0x53
Reported-by: Hyunwoo Kim <imv4bel@gmail.com>
Fixes: a770f6f28b ("KVM: MMU: Inherit a shadow page's guest level count from vcpu setup")
Cc: stable@vger.kernel.org
Signed-off-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Pull MM fixes from Andrew Morton:
"17 hotfixes. 15 are cc:stable. 16 are for MM.
There's a patch series from Lorenzo "mm: fix UAF caused by race
between ptdump and vmap pgtable freeing" which addresses a quite old
bug in the ptdump code.
And another series also from Lorenzo which fixes a four year old bug
in the huge_zero_folio handling.
A series from SJ fixes a few possible divide-by-zero issues which
Sashiko sniffed out. And a series which fixes handling of the
commit_inputs parameters.
The remainder are singletons, please see their changelogs for details"
* tag 'mm-hotfixes-stable-2026-08-06-18-44' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm:
mm/damon: adjust isolated pages stat for DAMOS_MIGRATE_{HOT,COLD}
mm/damon/ops-common: putback folios on invalid migrate nid
mm/huge_memory: initialise workingset state before folio split
mm/page_table_check: skip special zero mappings
mm/damon/lru_sort: skip damon_call() if ctx has not started
mm/damon/reclaim: skip damon_call() if ctx has not started
mm/damon/lru_sort: error out for >10000 active_mem_bp
samples/damon/mtier: error out for zero quota goal target values
mailmap: map old addresses to Danila Tikhonov
mm/huge_memory: separate out CONFIG_PERSISTENT_HUGE_ZERO_FOLIO logic
mm/huge_memory: fix huge_zero_pfn race
MAINTAINERS: update address for Brendan Jackman
mm/filemap: __filemap_add_folio() restore index before retrying
microblaze: restore the page alignment of swapper_pg_dir
arm64: remove redundant concurrent ptdump UAF mitigation
mm/ptdump: always stabilise against page table freeing using init_mm
mm/vmalloc: acquire init_mm lock on huge vmap to avoid ptdump UAF
We are frequently hitting the following splat during the riscv bpf
selftests:
00000000026dc75a: expected (7c3ff297) but got (00100073)
------------[ ftrace bug ]------------
ftrace failed to modify
[<ffffffff03c44c1c>] bpf_kfunc_common_test+0x4/0x20 [bpf_testmod]
actual: e7:82:c2:ce
Updating ftrace call site to call a different ftrace function
ftrace record flags: 80100002
(2)
expected tramp: ffffffff80043904
------------[ cut here ]------------
WARNING: kernel/trace/ftrace.c:2278 at ftrace_bug+0x46e/0x4b0, CPU#1: test_progs/98
...
[<ffffffff80008f4e>] ftrace_bug+0x46e/0x4b0
[<ffffffff803d3e86>] ftrace_replace_code+0x16e/0x170
[<ffffffff803d42b6>] ftrace_modify_all_code+0x12e/0x1b8
[<ffffffff800430f4>] arch_ftrace_update_code+0x14/0x28
[<ffffffff803e0324>] ftrace_startup+0x14c/0x2a0
[<ffffffff803e133c>] ftrace_startup_subops+0x584/0x1050
[<ffffffff804500e6>] register_ftrace_graph+0x4e6/0x1018
[<ffffffff804cf9f6>] register_fprobe_ips+0xc66/0x12f8
[<ffffffff8049abe8>] bpf_kprobe_multi_link_attach+0x5d8/0xe68
[<ffffffff8050fcaa>] __sys_bpf+0x3d5a/0x47f0
[<ffffffff805107ee>] __riscv_sys_bpf+0xae/0x168
[<ffffffff80034d78>] syscall_handler+0x60/0x100
[<ffffffff8228b4f4>] do_trap_ecall_u+0x174/0x208
[<ffffffff822b69c4>] handle_exception+0x16c/0x178
After debugging, it can be triggered by similar commands below:
```
echo do_nanosleep > set_ftrace_filter
echo function > current_tracer
echo 'p do_nanosleep' > kprobe_events
echo 1 > events/kprobes/enable
echo 'f do_nanosleep' > dynamic_events
echo 1 > events/fprobes/enable
```
The reason is that attaching a kprobe to an ftrace-traced function entry
replaces its initial auipc insn with ebreak. When ftrace_modify_call
later runs, it expects auipc insn, so verification fails and triggers
ftrace_bug.
The expected auipc logic remains conceptually unchanged, and kprobe
single-stepping ensures normal execution. Therefore, if the first insn
is ebreak, bypassing the check to continue patching the jalr insn is
safe and avoids ftrace failures.
Fixes: b2137c3b6d ("riscv: ftrace: prepare ftrace for atomic code patching")
Signed-off-by: Pu Lehui <pulehui@huawei.com>
Link: https://patch.msgid.link/20260802094929.3978390-1-pulehui@huaweicloud.com
[pjw@kernel.org: fixed reproducer in commit message]
Signed-off-by: Paul Walmsley <pjw@kernel.org>
Interaction between KVM_CAP_VM_MOVE_ENC_CONTEXT_FROM and
KVM_CAP_VM_COPY_ENC_CONTEXT_FROM can cause two separate issues:
- in sev_migrate_from(), when the destination KVM is a mirror, the mirror
entry is moved from the source's list to the owner's mirror_vms list,
without holding the owner's lock unlike other writers of the owner's
mirror list (sev_vm_copy_enc_context_from(), sev_vm_destroy()).
A concurrent COPY or destroy can race with sev_migrate_from() and
corrupt the list.
- In sev_vm_destroy(), the *owner* is still active and could receive
concurrently a KVM_CAP_VM_MOVE_ENC_CONTEXT_FROM that causes
sev->enc_context_owner to change. In this case the incorrect VM
receives kvm_put_kvm().
The second issue needs particular care because the owner could disappear
altogether (even though the race window is impossibly small) between
reading it and locking it. There is thus no way to perform the checks
under the owner lock without putting struct kvm under SLAB_TYPESAFE_BY_RCU
(which would allow kvm_get_kvm_safe() under RCU critical section).
It is much simpler to just use a global lock, since the critical
sections are so small and the new lock is always a leaf lock.
Fixes: b2125513df ("KVM: SEV: Allow SEV intra-host migration of VM with mirrors")
Cc: stable@vger.kernel.org
Reported-by: Shen Yongchao <grayhat@foxmail.com>
Link: https://lore.kernel.org/kvm/tencent_625C0F42824E542C72B34733392AF2C49709@qq.com/
Link: https://lore.kernel.org/kvm/tencent_DDC4E4352EC91CAC05A9A8F4E55E8C96730A@qq.com/
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
KVM: s390: Misc fixes for 7.2
Fix a bunch of small issues that came up during the previous round of
fixes.
They are mostly extremely unlikely races, but they should be fixed
nonetheless.
Red Hat is seeing multiple reports of Windows memory corruptions
(and consequent BSODs) with hv-tlbflush=on, on AMD processors only.
The crashes, while extremely rare, happen even with a stock configuration,
but with Driver Verifier enabled they can be detected after approximately
200 VM hours. In particular, Alexander Lougovski measured the following:
- on AMD Turin, 15 crashes in 3300 VM hours
- on AMD Milan, 2 crashes in 500 VM hours (there are fewer hours
here due to the host being smaller)
- on Intel Sapphire Rapids, 0 crashes in 8000 VM hours
- on AMD Turin with full TLB flush (not exactly this patch but
similar), no crashes in ~2 weeks of run time which should also
be ~7000 VM hours
For Turin, the microcode version was 0x0b002162, which (assuming
this is the same issue) should not be affected by the problem listed in
https://knowledge.broadcom.com/external/article/419026/bsod-on-virtual-machines-running-on-amd.html;
on the other hand that problem should not apply to earlier processors.
AMD has not provided any information or analysis yet, and when we asked
we didn't know yet that it reproduced on Milan as well.
As to the workload, Alexander threw more or less everything at the same
time at the VM:
- a full Windows Defender scan every 30 minutes
- a disk I/O job
- a loop doing repeated mmap of system files (mostly to hope that
it triggers some consistency check in the Windows memory manager)
- SQL Express 2022 + StressDB (1.6M rows), with the host doing queries
(75% write/25% read) via sqlcmd
Driver Verifier is able to detect BSODs more or less at the same time as
the pages are freed. They mostly happen in the Windows Defender filter
driver, but occasionally also in the networking stack (e.g., afd.sys)
or elsewhere in the filesystem stack (e.g., fltmgr.sys).
The flush is issued from kvm_hv_vcpu_flush_tlb(), which receives the
cross-CPU requests from the Hyper-V TLB flush hypercalls via a kfifo
and is invoked by the KVM_REQ_HV_TLB_FLUSH request. The mechanism is
the same for both Intel and AMD, and the handler for both vendors is
a simple INVVPID(ADDR)/INVLPGA instruction.
Because the request is handled on the destination CPU, there is a question
of what happens if the VM is migrated across physical CPUs. In that case,
the INVLPGA instruction would use a stale svm->vmcb->control.asid; but
if anything that might do an *unnecessary* flush (on an asid that's being
used for another VM) and then pre_svm_run() would force a full TLB rebuild.
So, for lack of better ideas, this patch forces a full ASID bump in
svm_flush_tlb_gva(). To avoid paying the price on Intel and also to
avoid unnecessary loops on AMD, the flush_tlb_gva op now returns whether
it did a full flush or not; kvm_hv_vcpu_flush_tlb() takes note and exits
its loops immediately. While there is an obvious performance impact,
about half of the benefit from Hyper-V tlbflush is preserved (10% vs. 20%
on the SQL Server workload).
kvm_mmu_invalidate_addr() is the only other caller of the flush_tlb_gva op.
The change would have a performance impact on every intercepted INVLPG and,
for nested SVM, on every L1 INVLPGA. For INVLPGA specifically, this covers
the same suspected issue but for nested hypervisors, so it is correct to
apply the workaround; for INVLPG on shadow paging, instead, the impact
would be stronger and, due to lack of data, for now the use of INVLPGA is
left in place in svm_flush_tlb_gva().
Analyzed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Analyzed-by: Alexander Lougovski <alougovs@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
- Add a mitigation for the attack vector of interrupting the saferet
sequence used in the SRSO mitigation and still poisoning the RSB.
Do that by emulating the saferet sequence and thus avoiding executing
a RET instruction.
* tag 'x86_bugs_saferet' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/bugs: Make Safe-RET robust against interrupt injection
Pull SoC fixes from Arnd Bergmann:
"The majority of the fixes this time is for Qualcomm devicetree files,
addressing various incorrect settings in chip specific dtsi files that
prevent some feature from working correctly.
Another three such issues are addressed on the Broadcom bcm5301x and
bcm2712 SoC platforms.
Two minor issues are addressed in nuvoton and aspeed specific SoC
drivers, and the MAINTAINERS file is updated to add Billy Tsai and
Ryan Chen as aspeed reviewers as well as clarify the NXP/Freescale
entries"
* tag 'soc-fixes-7.2-2' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc:
MAINTAINERS: add Ryan Chen and Billy Tsai as reviewer for ARM/ASPEED
ARM: dts: BCM5301X: EA9200: fix NVRAM size
ARM: dts: BCM5301X: fix PCIe controller 2 second interrupt
arm64: dts: qcom: eliza: Fix DSI1 phy reference clock rate
MAINTAINERS: ARM/FREESCALE: merge Layerscape entry into i.MX entry
ARM: npcm: Fix OF node refcount leaks in SMP setup
soc: aspeed: lpc-snoop: Fix usercopy overflow in snoop_file_read
arm64: dts: broadcom: bcm2712: Remove non-functional EL2 virtual timer
arm64: dts: qcom: sdm850-lenovo-yoga-c630: lower PSCI cluster idle
arm64: dts: qcom: sc8280xp: gaokun3: correct EC interrupt pin
arm64: dts: qcom: sc8280xp: add several missing pdc map entries
arm64: dts: qcom: sm8650: Fix IPA IMEM slice
arm64: dts: qcom: monaco: Add default GIC address cells
arm64: dts: qcom: purwa: Fix GPU IOMMU property
arm64: dts: qcom: glymur: fix QUP serial engine IRQs
arm64: dts: qcom: glymur: fix PCIe SMMU interrupts
microblaze handles TLB misses in software, and the handler builds the
address of the L1 entry by ORing the index into the page directory base
instead of adding it (hw_exception_handler.S):
bsrli r5, r3, PGDIR_SHIFT - 2
andi r5, r5, PAGE_SIZE - 4
/* Assume pgdir aligned on 4K boundary, no need for
"andi r4,r4,0xfffff003" */
or r4, r4, r5
lwi r4, r4, 0 /* Get L1 entry */
The index is masked to the low 12 bits, so the OR only works if those bits
of the base are zero -- which is exactly the assumption the comment states
and the reason the masking of the base can be skipped.
swapper_pg_dir had no alignment directive of its own. It was aligned
because it followed empty_zero_page in head.S, and that one carried the
.align 12:
.section .data
.global empty_zero_page
.align 12
empty_zero_page:
.space PAGE_SIZE
.global swapper_pg_dir
swapper_pg_dir:
.space PAGE_SIZE
Commit 6215d9f447 ("arch, mm: consolidate empty_zero_page") removed
empty_zero_page from head.S, and with it the .align 12 that -- despite
sitting next to empty_zero_page -- was what page aligned swapper_pg_dir.
Since then swapper_pg_dir lands wherever .data happens to put it, its low
bits are no longer zero, and every kernel TLB miss ORs the index into a
base with a nonzero offset. The resulting L1 lookups read the wrong
words, no valid translation is ever installed, and the kernel spins in
exceptions long before it can print anything. On qemu-system-microblazeel
(petalogix-s3adsp1800) the console stays completely silent at 100% CPU;
there is no oops and no guest error reported by qemu, which makes this
awkward to diagnose.
Give swapper_pg_dir the alignment it requires, rather than relying on a
neighbour to provide it.
microblaze has no noMMU variant left in mainline -- CONFIG_MMU is def_bool
y and mmu_defconfig is the only defconfig -- so this is not a corner case:
every mainline microblaze kernel since v7.1-rc1 fails to boot, including
the v7.1 release.
v7.0: swapper_pg_dir = 0xc05fd000 (aligned)
v7.1-rc1: swapper_pg_dir = 0xc0603140 (offset 320)
v7.1-rc1 + this fix: swapper_pg_dir = 0xc0604000 (aligned)
next-20260726: swapper_pg_dir = 0xc0615140 (offset 320)
next-20260726 + this fix: swapper_pg_dir = 0xc0616000 (aligned)
Verified on qemu-system-microblazeel (petalogix-s3adsp1800) with
mmu_defconfig and microblazeel gcc 12.5.0: v7.1-rc1 and next-20260726 both
print nothing at all without the fix, and both boot to userspace with it.
Link: https://lore.kernel.org/20260727215823.1422701-1-ramin.moussavi@yacoub.de
Fixes: 6215d9f447 ("arch, mm: consolidate empty_zero_page")
Signed-off-by: Ramin Moussavi <ramin.moussavi@yacoub.de>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
I hit the following on one of my machines:
mce: CPU0 BANK15 CMCI inherited storm
------------[ cut here ]------------
ODEBUG: assert_init not available (active state 0) object: (____ptrval____) object type: timer_list hint: 0x0
WARNING: lib/debugobjects.c:632 at debug_object_assert_init+0x178/0x230, CPU#0: swapper/0/0
CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted 7.2.0-rc5 #3 PREEMPTLAZY
RIP: 0010:debug_object_assert_init+0x18f/0x230
Call Trace:
<TASK>
__mod_timer
mce_timer_kick
cmci_discover
intel_init_cmci
mce_intel_feature_init
mcheck_cpu_init
identify_cpu
identify_boot_cpu
arch_cpu_finalize_init
start_kernel
A second splat follows right after, from timer_setup() finding that same
timer already queued:
ODEBUG: init active (active state 0) object: (____ptrval____) object type: timer_list hint: stub_timer+0x0/0x10
This is happening because CMCI storm detection is trying to modify the timer
before latter was properly set up.
Set up the timer first. __mcheck_cpu_setup_timer() only calls timer_setup(),
and depends on neither the generic nor the vendor init.
[ bp: Massage commit message. ]
Fixes: 1f68ce2a02 ("x86/mce: Handle Intel threshold interrupt storms")
Signed-off-by: Breno Leitao <leitao@debian.org>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Cc: stable@vger.kernel.org
Link: https://patch.msgid.link/20260803-mce_timer_init-v1-1-9539db424330@debian.org
nuvoton: First batch of ARM arch fixes for 7.2
Again a one-off change, fixing OF resource leaks in the SMP-bringup code for the
NPCM7xx SoCs.
* tag 'nuvoton-7.2-arm-fixes-0' of https://git.kernel.org/pub/scm/linux/kernel/git/bmc/linux:
ARM: npcm: Fix OF node refcount leaks in SMP setup
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
If creating a protected vCPU in kvm_s390_pv_create_cpu() fails,
kvm_s390_pv_destroy_cpu() was called, which checks whether the vCPU has
a PV handle and exits doing nothing otherwise. At that point, due to
not having created the protected vCPU, the PV handle will not be set,
and kvm_s390_pv_destroy_cpu() will do nothing, thus leaking the
allocated memory.
Fix by factoring out the code to free and reset a PV vCPU; call it from
kvm_s390_pv_destroy_cpu() and kvm_s390_pv_create_cpu().
Opportunistically fix the return value of kvm_s390_pv_destroy_cpu() in
case of errors: return -EIO instead if EIO.
Fixes: d4074324b0 ("KVM: s390: pv: avoid double free of sida page")
Reviewed-by: Steffen Eiden <seiden@linux.ibm.com>
Reviewed-by: Janosch Frank <frankja@linux.ibm.com>
Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Message-ID: <20260803124040.126471-14-imbrenda@linux.ibm.com>
If a fatal signal is pending while trying to fault-in a page, return
-EINTR instead of -EAGAIN.
Also fix unpack_one() to handle -EINTR properly.
Fixes: e907ae5301 ("KVM: s390: Add helper functions for fault handling")
Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Message-ID: <20260803124040.126471-12-imbrenda@linux.ibm.com>
The mmu cache is the first thing that is allocated in
kvm_arch_vcpu_create(), but in case of failure it was not freed.
Fix by freeing the mmu cache in case of failure.
Refactor kvm_arch_vcpu_create() to use scope-based cleanup instead of
gotos.
Fixes: e38c884df9 ("KVM: s390: Switch to new gmap")
Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Message-ID: <20260803124040.126471-11-imbrenda@linux.ibm.com>
gmap_remove_child() needs to be called while holding the children_lock
of the parent gmap. This was not the case in the error handling path of
kvm_arch_vcpu_create() for UCONTROL guests.
Fix by adding the missing lock.
Fixes: e38c884df9 ("KVM: s390: Switch to new gmap")
Reviewed-by: Steffen Eiden <seiden@linux.ibm.com>
Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Message-ID: <20260803124040.126471-10-imbrenda@linux.ibm.com>
When a memslot is removed, all ptes that mapped the slot are cleared or
even deallocated. If this happens while the system is in migration
mode, and if cmma-dirty pages are removed, the cmma-dirty counter will
not reflect reality.
Fix by appropriately decrementing the cmma-dirty counter when removing
a memslot.
Opportunistically improve kvm_arch_commit_memory_region() to use
__free() for the struct kvm_s390_mmu_cache.
Fixes: e38c884df9 ("KVM: s390: Switch to new gmap")
Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Message-ID: <20260803124040.126471-9-imbrenda@linux.ibm.com>
An unlikely race between __do_essa() and kvm_s390_vm_start_migration(),
kvm_s390_vm_stop_migration(), or dat_get_cmma() was possible.
Fix by locking kvm->slots_arch_lock. Since this is not a hot path, the
overhead of an additional mutex is negligible.
Fixes: e38c884df9 ("KVM: s390: Switch to new gmap")
Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Message-ID: <20260803124040.126471-8-imbrenda@linux.ibm.com>
If kvm_s390_set_cmma_bits() is asked to set CMMA values outside of a
memslot, PGM_ADDRESSING (5) is returned, instead of a negative error
value.
Same issue with kvm_s390_{g,s}et_skeys(), kvm_s390_keyop(), and
dat_reset_reference_bit().
Fix by returning -EFAULT whenever the return value would be > 0, which
is consistent with the behaviour before the gmap rewrite.
Fixes: e38c884df9 ("KVM: s390: Switch to new gmap")
Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Message-ID: <20260803124040.126471-7-imbrenda@linux.ibm.com>
When cleaning up a UCONTROL VM, sca_clear_ext_call() will touch memory
outside of the allocated ESCA block, and UCONTROL VMs don't even use
ESCA.
Fix by not touching ESCA for UCONTROL VMs, and fence the
KVM_S390_INTERRUPT ioctl altogether. Add extra checks in
sca_ext_call_pending() and sca_inject_ext_call() to make sure UCONTROL
VMs won't touch ESCA.
Fencing does not cause regressions with userspace, since UCONTROL VMs
never used KVM_S390_INTERRUPT ioctls.
Fixes: 7d43bafcff ("KVM: s390: Make provisions for ESCA utilization")
Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Message-ID: <20260803124040.126471-6-imbrenda@linux.ibm.com>
If an attempt is made to create a vCPU with an already existing ID,
the duplicated vCPU will be destroyed. When destroying a vCPU, its
ESCA entry will be cleared. In the above scenario, the spurious
duplicate vCPU is destroyed, but the ESCA entry corresponding to the
original vCPU is cleared.
Fix by skipping clearing the ESCA entry if the vCPU creation was not
successful, i.e. if the vcpu->arch.initialized is still zero.
Reviewed-by: Janosch Frank <frankja@linux.ibm.com>
Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Fixes: abf4a71ed9 ("KVM: s390: Unlink vcpu on destroy - v2")
[ Added Fixes tag while picking -- Claudio ]
Message-ID: <20260803124040.126471-5-imbrenda@linux.ibm.com>
In some cases kvm_s390_vcpu_unsetup_cmma() can be called with a 0
cbrlo; in such cases, if running with V != R, free_page() will attempt
to free physical page 0.
Fix by freeing cbrlo only if it's non-zero.
Fixes: b31605c12f ("KVM: s390: make cmma usage conditionally")
Fixes: 29b40f105e ("KVM: s390: protvirt: Add initial vm and cpu lifecycle handling")
Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Message-ID: <20260803124040.126471-4-imbrenda@linux.ibm.com>
If VM creation fails early in kvm_arch_init_vm(), the cleanup code
tries to free up the SCA, even though the address is 0. Due to using
free_pages_exact(), only the first page is skipped, accidentally
freeing pages 1, 2, and 3.
Fix by checking whether the pointer is NULL before attempting to free
the SCA in sca_dispose().
Fixes: e72753ed12 ("KVM: s390: Use ESCA instead of BSCA at VM init")
Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Message-ID: <20260803124040.126471-3-imbrenda@linux.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@linux.ibm.com>
Reviewed-by: Janosch Frank <frankja@linux.ibm.com>
When creating a new vCPU, kvm_vm_ioctl_create_vcpu() will call
kvm_arch_vcpu_postcreate() after the file descriptor for the new vCPU
has been created. The new file descriptor has not been returned yet,
but a malicious userspace program could try to guess it.
If a malicious userspace program manages to start the newly created vCPU
before kvm_arch_vcpu_postcreate() is called, __vcpu_run() will try to
dereference vcpu->arch.gmap and trigger a NULL pointer dereference.
Fix this by adding a new field to struct kvm_vcpu_arch to keep track of
the initialization status of the vCPU. Refuse to run a vCPU that is not
fully initialized.
Fixes: dafd032a15 ("KVM: s390: move vcpu specific initalization to a later point")
Fixes: e38c884df9 ("KVM: s390: Switch to new gmap")
Reviewed-by: Steffen Eiden <seiden@linux.ibm.com>
Reviewed-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@linux.ibm.com>
Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Message-ID: <20260803124040.126471-2-imbrenda@linux.ibm.com>
Pull RISC-V fixes from Paul Walmsley:
- Fix swiotlb initialization on systems where DRAM is located above
4GiB (such as the Tenstorrent Blackhole cards)
- Fix an out-of-bounds access in the memory hot-remove code that can
occur on Sv39 and Sv48 systems
- Avoid oopsing during boot if the SBI component of the unaligned
access performance checking code loses a race against __init function
freeing
- Avoid attempting to install the debug-enabled vDSO when it shouldn't
be built due to !CONFIG_MMU
- Avoid some sparse warnings by adding missing __iomem notations in
get_cycles{,_hi}()
- Drop an unnecessary runtime warning in the SiFive errata handler
* tag 'riscv-for-linus-7.2-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux:
riscv: vdso: Only try to install vDSO when present
riscv: mm: Fix out-of-bounds page-table walk during memory hot-remove
riscv: drop __init from vec_check_unaligned_access_speed_all_cpus
riscv: mm: fix SWIOTLB initialization for systems with DRAM above 4GB
riscv/sifive: remove warning in errata
riscv: time: Add missing __iomem in get_cycles() and get_cycles_hi()
Pull s390 updates from Vasily Gorbik:
- Fix PCI MMIO write syscall falsely reporting success for mappings not
valid for MMIO when MIO is unavailable by returning -EFAULT
- Fix CPRB parameter buffer overflows in zcrypt CCA AES cipher and ECC
private key conversion by rejecting oversized key tokens
- Fix buffer overreads and length underflow in pkey and zcrypt CCA
token validation by checking length fields against actual buffer
sizes
- Fix out of bounds permission bitmap access in zcrypt EP11 admin CPRB
filtering on custom device nodes by using AP_DOMAINS as the limit
- Fix speculative permission bitmap reads in zcrypt CCA and EP11 admin
CPRB handling by sanitizing user controlled domain indexes
- Fix sensitive key material left in zcrypt CCA clear key import
buffers by scrubbing CPRB and temporary buffers after use
* tag 's390-7.2-6' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
s390/zcrypt: Fix missing mem scrub at clear key import in cca_clr2cipherkey()
s390/zcrypt: Close speculative mem read possibility
s390/zcrypt: Fix wrong domain value verification with EP11 CPRBs
s390/zcrypt: Fix buffer over-read in cca_cipher2protkey
s390/zcrypt: Validate length for CCA ECC private key requests
s390/zcrypt: Validate length for CCA AES cipher key requests
s390/pci: Fix s390_pci_mmio_write syscall error return without MIO
Pull misc x86 fixes from Ingo Molnar:
- Fix the boot-time memcmp() asm implementation's constraints
and optimization properties (Mauricio Faria de Oliveira)
- Move the 0xd0...0xd7 AMD Zen5 model range from the Zen6
range where it mistakenly ended up (Pratik Vishwakarma)
* tag 'x86-urgent-2026-08-02' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/CPU/AMD: Carve out a Zen5 models range
x86/boot: Add volatile, clobbers and zero-length test in memcmp()
Pull UML fix from Richard Weinberger:
- Fix use-after-free in UML's vector networking driver
* tag 'uml-for-linus-7.2-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/uml/linux:
um: vector: fix use-after-free in vector_mmsg_rx()
Pull misc fixes from Andrew Morton:
"12 hotfixes. 6 are cc:stable. 9 are for MM.
There's a two-patch series from Nico which fixes a couple of PMD level
mTHP accounting bugs and a two-patch series from Chris Gellermann
which addresses mishandling of getline() in selftests. All the
remainder are singletons - please see the changelogs for details"
* tag 'mm-hotfixes-stable-2026-07-30-19-30' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm:
selftests/mm: fix potential wild pointer access of getline due to missing init
selftests/clone3: fix wild pointer access of getline due to missing init
mm/page_reporting: use system_freezable_wq to fix UAF during suspend
mm: vmscan: abort proactive reclaim early when freezing for suspend
MAINTAINERS: update Nico Pache's email address
arm64, mailmap: update email address for Peter Collingbourne
MAINTAINERS: update address for Burak Emir
mm/huge_memory: unlock i_mmap_rwsem before releasing after-split folios
riscv/mm: use physical alignment for vmemmap_start_pfn
mm/migrate: exclude hugetlb folios from MTHP_STAT_NR_ANON accounting
mm: decrement MTHP_STAT_NR_ANON in free_zone_device_folio()
mm: memcg: initialize *locked in memcg1_oom_prepare() stub
On a machine without PCI memory-I/O (MIO) support or when running with
pci=nomio the s390 specific PCI MMIO write syscall checks if the MMIO
cookie is above ZPCI_IOMAP_ADDR_BASE as a sanity check before even
trying to perform the MMIO. If this check fails the return value was
left unchanged and thus 0 from prior operations falsely indicating
success. This could potentially confuse user-space into falsely
believing the MMIO, on a mapping not valid for MMIO was successful.
Fix this by setting the return value to -EFAULT prior to the check
following the same pattern as elsewhere in the same function.
Cc: stable@vger.kernel.org
Reviewed-by: Julian Ruess <julianr@linux.ibm.com>
Reviewed-by: Farhan Ali <alifm@linux.ibm.com>
Fixes: a67a88b0b8 ("s390/pci: remove races against pte updates")
Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
