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Linux kernel
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Pull perf tools fixes from Arnaldo Carvalho de Melo:
- Fix writing bpf_prog (infos|btfs)_cnt to data file, to not generate
invalid perf.data files in some corner cases.
- Fix 'perf top' segfault by ensuring libbfd is initialized. This is an
opt-in feature due to license incompatibilities.
- Fix segfault in 'perf lock' due to missing kernel map.
- Fix 'perf lock contention' test.
- Don't fail fast path detection if binutils-devel isn't available.
- Sync KVM's vmx.h with the kernel to pick SEAMCALL exit reason.
* tag 'perf-tools-fixes-for-v6.18-2-2025-11-16' of git://git.kernel.org/pub/scm/linux/kernel/git/perf/perf-tools:
perf libbfd: Ensure libbfd is initialized prior to use
perf test: Fix lock contention test
perf lock: Fix segfault due to missing kernel map
tools headers UAPI: Sync KVM's vmx.h with the kernel to pick SEAMCALL exit reason
perf build: Don't fail fast path feature detection when binutils-devel is not available
perf header: Write bpf_prog (infos|btfs)_cnt to data file
Pull misc fixes from Andrew Morton:
"7 hotfixes. 5 are cc:stable, 4 are against mm/
All are singletons - please see the respective changelogs for details"
* tag 'mm-hotfixes-stable-2025-11-16-10-40' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm:
mm, swap: fix potential UAF issue for VMA readahead
selftests/user_events: fix type cast for write_index packed member in perf_test
lib/test_kho: check if KHO is enabled
mm/huge_memory: fix folio split check for anon folios in swapcache
MAINTAINERS: update David Hildenbrand's email address
crash: fix crashkernel resource shrink
mm: fix MAX_FOLIO_ORDER on powerpc configs with hugetlb
Multiple threads may be creating and destroying BFD objects in
situations like `perf top`.
Without appropriate initialization crashes may occur during libbfd's
cache management.
BFD's locks require recursive mutexes, add support for these.
Committer testing:
This happens only when building with 'make BUILD_NONDISTRO=1' and having
the binutils-devel package (or equivalent) installed, i.e. linking with
binutils devel files, an opt-in perf build.
Before:
root@x1:~# perf top
perf: Segmentation fault
-------- backtrace --------
<SNIP multiple failed attempts at printing a backtrace>
root@x1:~#
After this patch it works as before.
Closes: https://lore.kernel.org/lkml/aQt66zhfxSA80xwt@gentoo.org/
Fixes: 95931d9a594dd0b5 ("perf libbfd: Move libbfd functionality to its own file")
Reported-by: Guilherme Amadio <amadio@gentoo.org>
Signed-off-by: Ian Rogers <irogers@google.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Pull firewire fixes from Takashi Sakamoto:
"This includes some fixes for the topology map, newly introduced in
v6.18 kernel"
* tag 'firewire-fixes-6.18-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394:
firewire: core: fix to update generation field in topology map
firewire: core: Initialize topology_map.lock
Since commit 78524b05f1a3 ("mm, swap: avoid redundant swap device
pinning"), the common helper for allocating and preparing a folio in the
swap cache layer no longer tries to get a swap device reference
internally, because all callers of __read_swap_cache_async are already
holding a swap entry reference. The repeated swap device pinning isn't
needed on the same swap device.
Caller of VMA readahead is also holding a reference to the target entry's
swap device, but VMA readahead walks the page table, so it might encounter
swap entries from other devices, and call __read_swap_cache_async on
another device without holding a reference to it.
So it is possible to cause a UAF when swapoff of device A raced with
swapin on device B, and VMA readahead tries to read swap entries from
device A. It's not easy to trigger, but in theory, it could cause real
issues.
Make VMA readahead try to get the device reference first if the swap
device is a different one from the target entry.
Link: https://lkml.kernel.org/r/20251111-swap-fix-vma-uaf-v1-1-41c660e58562@tencent.com
Fixes: 78524b05f1a3 ("mm, swap: avoid redundant swap device pinning")
Suggested-by: Huang Ying <ying.huang@linux.alibaba.com>
Signed-off-by: Kairui Song <kasong@tencent.com>
Acked-by: Chris Li <chrisl@kernel.org>
Cc: Baoquan He <bhe@redhat.com>
Cc: Barry Song <baohua@kernel.org>
Cc: Kemeng Shi <shikemeng@huaweicloud.com>
Cc: Nhat Pham <nphamcs@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Couple of independent fixes:
1. Wire in SIGSEGV handler that terminates the test with a failure code.
2. Use "--lock-cgroup" instead of "-g"; "-g" was proposed but never
merged. See commit 4d1792d0a2564caf ("perf lock contention: Add
--lock-cgroup option")
3. Call cleanup() on every normal exit so trap_cleanup() doesn't mistake
it for an unexpected signal and emit a false-negative "Unexpected
signal in main" message.
Before patch:
# ./perf test -vv "lock contention"
85: kernel lock contention analysis test:
--- start ---
test child forked, pid 610711
Testing perf lock record and perf lock contention
Testing perf lock contention --use-bpf
Testing perf lock record and perf lock contention at the same time
Testing perf lock contention --threads
Testing perf lock contention --lock-addr
Testing perf lock contention --lock-cgroup
Unexpected signal in test_aggr_cgroup
---- end(0) ----
85: kernel lock contention analysis test : Ok
After patch:
# ./perf test -vv "lock contention"
85: kernel lock contention analysis test:
--- start ---
test child forked, pid 602637
Testing perf lock record and perf lock contention
Testing perf lock contention --use-bpf
Testing perf lock record and perf lock contention at the same time
Testing perf lock contention --threads
Testing perf lock contention --lock-addr
Testing perf lock contention --lock-cgroup
Testing perf lock contention --type-filter (w/ spinlock)
Testing perf lock contention --lock-filter (w/ tasklist_lock)
Testing perf lock contention --callstack-filter (w/ unix_stream)
[Skip] Could not find 'unix_stream'
Testing perf lock contention --callstack-filter with task aggregation
[Skip] Could not find 'unix_stream'
Testing perf lock contention --cgroup-filter
Testing perf lock contention CSV output
---- end(0) ----
85: kernel lock contention analysis test : Ok
Reviewed-by: Ian Rogers <irogers@google.com>
Signed-off-by: Ravi Bangoria <ravi.bangoria@amd.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ananth Narayan <ananth.narayan@amd.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@linaro.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sandipan Das <sandipan.das@amd.com>
Cc: Santosh Shukla <santosh.shukla@amd.com>
Cc: Tycho Andersen <tycho@kernel.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Pull EDAC fixes from Borislav Petkov:
- In Versalnet, handle the reporting of non-standard hw errors whose
information can come in more than one remote processor message.
- Explicitly reenable ECC checking after a warm reset in Altera OCRAM
as those registers are reset to default otherwise
- Fix single-bit error injection in Altera EDAC to not inject errors
directly in ECC RAM and thus lead to false double-bit errors due to
same ECC RAM being in concurrent use
* tag 'edac_urgent_for_v6.18_rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/ras/ras:
EDAC/altera: Use INTTEST register for Ethernet and USB SBE injection
EDAC/altera: Handle OCRAM ECC enable after warm reset
EDAC/versalnet: Handle split messages for non-standard errors
The generation field of topology map is updated after initialized by zero.
The updated value of generation field is always zero, and is against
specification.
This commit fixes the bug.
Fixes: 7d138cb269db ("firewire: core: use spin lock specific to topology map")
Link: https://lore.kernel.org/r/20251114144421.415278-1-o-takashi@sakamocchi.jp
Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Accessing 'reg.write_index' directly triggers a -Waddress-of-packed-member
warning due to potential unaligned pointer access:
perf_test.c:239:38: warning: taking address of packed member 'write_index'
of class or structure 'user_reg' may result in an unaligned pointer value
[-Waddress-of-packed-member]
239 | ASSERT_NE(-1, write(self->data_fd, ®.write_index,
| ^~~~~~~~~~~~~~~
Since write(2) works with any alignment. Casting '®.write_index'
explicitly to 'void *' to suppress this warning.
Link: https://lkml.kernel.org/r/20251106095532.15185-1-ankitkhushwaha.linux@gmail.com
Fixes: 42187bdc3ca4 ("selftests/user_events: Add perf self-test for empty arguments events")
Signed-off-by: Ankit Khushwaha <ankitkhushwaha.linux@gmail.com>
Cc: Beau Belgrave <beaub@linux.microsoft.com>
Cc: "Masami Hiramatsu (Google)" <mhiramat@kernel.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: sunliming <sunliming@kylinos.cn>
Cc: Wei Yang <richard.weiyang@gmail.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Kernel maps are encoded in PERF_RECORD_MMAP2 samples but "perf lock
report" and "perf lock contention" do not process MMAP2 samples.
Because of that, machine->vmlinux_map stays NULL and any later access
triggers a segmentation fault.
Fix it by adding ->mmap2() callbacks.
Fixes: 53b00ff358dc75b1 ("perf record: Make --buildid-mmap the default")
Reported-by: Tycho Andersen (AMD) <tycho@kernel.org>
Reviewed-by: Ian Rogers <irogers@google.com>
Signed-off-by: Ravi Bangoria <ravi.bangoria@amd.com>
Tested-by: Tycho Andersen (AMD) <tycho@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ananth Narayan <ananth.narayan@amd.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@linaro.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sandipan Das <sandipan.das@amd.com>
Cc: Santosh Shukla <santosh.shukla@amd.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Pull s390 fix from Heiko Carstens:
- Fix a bug in the __ptep_rdp() inline assembly which may lead to
missing TLB flushes
* tag 's390-6.18-4' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
s390/mm: Fix __ptep_rdp() inline assembly
The current single-bit error injection mechanism flips bits directly in ECC RAM
by performing write and read operations. When the ECC RAM is actively used by
the Ethernet or USB controller, this approach sometimes trigger a false
double-bit error.
Switch both Ethernet and USB EDAC devices to use the INTTEST register
(altr_edac_a10_device_inject_fops) for single-bit error injection, similar to
the existing double-bit error injection method.
Fixes: 064acbd4f4ab ("EDAC, altera: Add Stratix10 peripheral support")
Signed-off-by: Niravkumar L Rabara <niravkumarlaxmidas.rabara@altera.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Acked-by: Dinh Nguyen <dinguyen@kernel.org>
Cc: stable@vger.kernel.org
Link: https://patch.msgid.link/20251111081333.1279635-1-niravkumarlaxmidas.rabara@altera.com
Lockdep barfs on the new uninitialized spinlock.
Initialize it.
protip: enable lockdep (CONFIG_PROVE_LOCKING=y) when
doing locking changes
firewire_ohci 0000:02:01.1: added OHCI v1.10 device as card 0, 4 IR + 4 IT contexts, quirks 0x11
INFO: trying to register non-static key.
The code is fine but needs lockdep annotation, or maybe
you didn't initialize this object before use?
turning off the locking correctness validator.
CPU: 0 UID: 0 PID: 1042 Comm: irq/17-firewire Not tainted 6.17.0-rc2-cl-bisect2-00026-g7d138cb269db #136 PREEMPT
Hardware name: Dell Inc. Latitude E5400 /0D695C, BIOS A19 06/13/2013
Call Trace:
<TASK>
dump_stack_lvl+0x6d/0xa0
register_lock_class+0x783/0x790
? find_held_lock+0x2b/0x80
? __mod_timer+0x110/0x320
? __mod_timer+0x110/0x320
__lock_acquire+0x405/0x2600
lock_acquire+0xca/0x2e0
? fw_core_handle_bus_reset+0x888/0xca0 [firewire_core]
? fw_core_handle_bus_reset+0x878/0xca0 [firewire_core]
? fw_core_handle_bus_reset+0x878/0xca0 [firewire_core]
_raw_spin_lock+0x2e/0x40
? fw_core_handle_bus_reset+0x888/0xca0 [firewire_core]
fw_core_handle_bus_reset+0x888/0xca0 [firewire_core]
handle_selfid_complete_event+0x35c/0x7a0 [firewire_ohci]
? irq_thread+0x8d/0x280
irq_thread_fn+0x18/0x50
irq_thread+0x15a/0x280
? irq_check_status_bit+0x100/0x100
? lockdep_hardirqs_on+0x78/0x100
? irq_finalize_oneshot.part.0+0xc0/0xc0
? irq_forced_thread_fn+0x60/0x60
kthread+0x114/0x200
? kthreads_online_cpu+0x110/0x110
ret_from_fork+0x158/0x1e0
? kthreads_online_cpu+0x110/0x110
ret_from_fork_asm+0x11/0x20
</TASK>
Reported-by: Erhard Furtner <erhard_f@mailbox.org>
Fixes: 7d138cb269db ("firewire: core: use spin lock specific to topology map")
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
We must check whether KHO is enabled prior to issuing KHO commands,
otherwise KHO internal data structures are not initialized.
Link: https://lkml.kernel.org/r/20251106220635.2608494-1-pasha.tatashin@soleen.com
Fixes: b753522bed0b ("kho: add test for kexec handover")
Signed-off-by: Pasha Tatashin <pasha.tatashin@soleen.com>
Reported-by: kernel test robot <oliver.sang@intel.com>
Closes: https://lore.kernel.org/oe-lkp/202511061629.e242724-lkp@intel.com
Reviewed-by: Pratyush Yadav <pratyush@kernel.org>
Reviewed-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Cc: Alexander Graf <graf@amazon.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
To pick the changes in:
9d7dfb95da2cb5c1 ("KVM: VMX: Inject #UD if guest tries to execute SEAMCALL or TDCALL")
The 'perf kvm-stat' tool uses the exit reasons that are included in the
VMX_EXIT_REASONS define, this new SEAMCALL isn't included there (TDCALL
is), so shouldn't be causing any change in behaviour, this patch ends up
being just addressess the following perf build warning:
Warning: Kernel ABI header differences:
diff -u tools/arch/x86/include/uapi/asm/vmx.h arch/x86/include/uapi/asm/vmx.h
Please see tools/include/uapi/README for further details.
Cc: Sean Christopherson <seanjc@google.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Pull x86 fixes from Ingo Molnar:
- Update the list of AMD microcode minimum Entrysign revisions
- Add additional fixed AMD RDSEED microcode revisions
- Update the language transliteration for Kiryl Shutsemau's name
in the MAINTAINERS entry
* tag 'x86-urgent-2025-11-15' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/microcode/AMD: Add Zen5 model 0x44, stepping 0x1 minrev
x86/CPU/AMD: Add additional fixed RDSEED microcode revisions
MAINTAINERS: Update name spelling
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