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Pull x86 fixes from Borislav Petkov:
- Remove a transitional asm/cpuid.h header which was added only as a
fallback during cpuid helpers reorg
- Initialize reserved fields in the SVSM page validation calls
structure to zero in order to allow for future structure extensions
- Have the sev-guest driver's buffers used in encryption operations be
in linear mapping space as the encryption operation can be offloaded
to an accelerator
- Have a read-only MSR write when in an AMD SNP guest trap to the
hypervisor as it is usually done. This makes the guest user
experience better by simply raising a #GP instead of terminating said
guest
- Do not output AVX512 elapsed time for kernel threads because the data
is wrong and fix a NULL pointer dereferencing in the process
- Adjust the SRSO mitigation selection to the new attack vectors
* tag 'x86_urgent_for_v6.17_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/cpuid: Remove transitional <asm/cpuid.h> header
x86/sev: Ensure SVSM reserved fields in a page validation entry are initialized to zero
virt: sev-guest: Satisfy linear mapping requirement in get_derived_key()
x86/sev: Improve handling of writes to intercepted TSC MSRs
x86/fpu: Fix NULL dereference in avx512_status()
x86/bugs: Select best SRSO mitigation
Pull locking fixes from Borislav Petkov:
- Make sure sanity checks down in the mutex lock path happen on the
correct type of task so that they don't trigger falsely
- Use the write unsafe user access pairs when writing a futex value to
prevent an error on PowerPC which does user read and write accesses
differently
* tag 'locking_urgent_for_v6.17_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
locking: Fix __clear_task_blocked_on() warning from __ww_mutex_wound() path
futex: Use user_write_access_begin/_end() in futex_put_value()
All CPUID call sites were updated at commit:
968e30006807 ("x86/cpuid: Set <asm/cpuid/api.h> as the main CPUID header")
to include <asm/cpuid/api.h> instead of <asm/cpuid.h>.
The <asm/cpuid.h> header was still retained as a wrapper, just in case
some new code in -next started using it. Now that everything is merged
to Linus' tree, remove the header.
Signed-off-by: Ahmed S. Darwish <darwi@linutronix.de>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/20250815070227.19981-2-darwi@linutronix.de
Pull rust fixes from Miguel Ojeda:
- Workaround 'rustdoc' target modifiers bug in Rust >= 1.88.0. It will
be fixed in Rust 1.90.0 (expected 2025-09-18).
- Clean 'rustdoc' output before running it to avoid confusing the tool
when files from previous versions remain.
* tag 'rust-fixes-6.17' of git://git.kernel.org/pub/scm/linux/kernel/git/ojeda/linux:
rust: kbuild: clean output before running `rustdoc`
rust: workaround `rustdoc` target modifiers bug
The __clear_task_blocked_on() helper added a number of sanity
checks ensuring we hold the mutex wait lock and that the task
we are clearing blocked_on pointer (if set) matches the mutex.
However, there is an edge case in the _ww_mutex_wound() logic
where we need to clear the blocked_on pointer for the task that
owns the mutex, not the task that is waiting on the mutex.
For this case the sanity checks aren't valid, so handle this
by allowing a NULL lock to skip the additional checks.
K Prateek Nayak and Maarten Lankhorst also pointed out that in
this case where we don't hold the owner's mutex wait_lock, we
need to be a bit more careful using READ_ONCE/WRITE_ONCE in both
the __clear_task_blocked_on() and __set_task_blocked_on()
implementations to avoid accidentally tripping WARN_ONs if two
instances race. So do that here as well.
This issue was easier to miss, I realized, as the test-ww_mutex
driver only exercises the wait-die class of ww_mutexes. I've
sent a patch[1] to address this so the logic will be easier to
test.
[1]: https://lore.kernel.org/lkml/20250801023358.562525-2-jstultz@google.com/
Fixes: a4f0b6fef4b0 ("locking/mutex: Add p->blocked_on wrappers for correctness checks")
Closes: https://lore.kernel.org/lkml/68894443.a00a0220.26d0e1.0015.GAE@google.com/
Reported-by: syzbot+602c4720aed62576cd79@syzkaller.appspotmail.com
Reported-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: John Stultz <jstultz@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: K Prateek Nayak <kprateek.nayak@amd.com>
Acked-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Tested-by: K Prateek Nayak <kprateek.nayak@amd.com>
Link: https://lore.kernel.org/r/20250805001026.2247040-1-jstultz@google.com
In order to support future versions of the SVSM_CORE_PVALIDATE call, all
reserved fields within a PVALIDATE entry must be set to zero as an SVSM should
be ensuring all reserved fields are zero in order to support future usage of
reserved areas based on the protocol version.
Fixes: fcd042e86422 ("x86/sev: Perform PVALIDATE using the SVSM when not at VMPL0")
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Joerg Roedel <joerg.roedel@amd.com>
Cc: <stable@kernel.org>
Link: https://lore.kernel.org/7cde412f8b057ea13a646fb166b1ca023f6a5031.1755098819.git.thomas.lendacky@amd.com
Pull ata fixes from Damien Le Moal:
- Fix a regression affecting old IDE/PATA device scan and introduced by
the recent link power management cleanups & fixes. The regression
prevented devices from being properly detected (me)
- Fix command duration limits (CDL) feature control: attempting to
enable the feature while NCQ commands are being executed resulted in
a silent failure to enable CDL when needed (Igor)
* tag 'ata-ata-6.17-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/libata/linux:
ata: libata-scsi: Fix CDL control
ata: libata-eh: Fix link state check for IDE/PATA ports
`rustdoc` can get confused when generating documentation into a folder
that contains generated files from other `rustdoc` versions.
For instance, running something like:
rustup default 1.78.0
make LLVM=1 rustdoc
rustup default 1.88.0
make LLVM=1 rustdoc
may generate errors like:
error: couldn't generate documentation: invalid template: last line expected to start with a comment
|
= note: failed to create or modify "./Documentation/output/rust/rustdoc/src-files.js"
Thus just always clean the output folder before generating the
documentation -- we are anyway regenerating it every time the `rustdoc`
target gets called, at least for the time being.
Cc: stable@vger.kernel.org # Needed in 6.12.y and later (Rust is pinned in older LTSs).
Reported-by: Daniel Almeida <daniel.almeida@collabora.com>
Closes: https://rust-for-linux.zulipchat.com/#narrow/channel/288089/topic/x/near/527201113
Reviewed-by: Tamir Duberstein <tamird@kernel.org>
Link: https://lore.kernel.org/r/20250726133435.2460085-1-ojeda@kernel.org
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Commit cec199c5e39b ("futex: Implement FUTEX2_NUMA") introduced the
futex_put_value() helper to write a value to the given user
address.
However, it uses user_read_access_begin() before the write. For
architectures that differentiate between read and write accesses, like
PowerPC, futex_put_value() fails with -EFAULT.
Fix that by using the user_write_access_begin/user_write_access_end() pair
instead.
Fixes: cec199c5e39b ("futex: Implement FUTEX2_NUMA")
Signed-off-by: Waiman Long <longman@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/all/20250811141147.322261-1-longman@redhat.com
Commit
7ffeb2fc2670 ("x86/sev: Document requirement for linear mapping of guest request buffers")
added a check that requires the guest request buffers to be in the linear
mapping. The get_derived_key() function was passing a buffer that was
allocated on the stack, resulting in the call to snp_send_guest_request()
returning an error.
Update the get_derived_key() function to use an allocated buffer instead
of a stack buffer.
Fixes: 7ffeb2fc2670 ("x86/sev: Document requirement for linear mapping of guest request buffers")
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Cc: <stable@kernel.org>
Link: https://lore.kernel.org/9b764ca9fc79199a091aac684c4926e2080ca7a8.1752698495.git.thomas.lendacky@amd.com
Pull SCSI fixes from James Bottomley:
"One core change removing the 'w' access flag of attributes that don't
have a set routine (and therefore can't be written to) which should
have no practical impact. The big scsi_debug update is caused by
reformatting lots of arrays and the rest of the bug fixes in drivers
are trivial"
* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
scsi: ufs: core: Remove error print for devm_add_action_or_reset()
scsi: ufs: mediatek: Fix out-of-bounds access in MCQ IRQ mapping
scsi: lpfc: Remove redundant assignment to avoid memory leak
scsi: lpfc: Fix wrong function reference in a comment
scsi: ufs: core: Fix interrupt handling for MCQ Mode
scsi: scsi_debug: Make read-only arrays static const
scsi: core: sysfs: Correct sysfs attributes access rights
Delete extra checks for the ATA_DFLAG_CDL_ENABLED flag that prevent
SET FEATURES command from being issued to a drive when NCQ commands
are active.
ata_mselect_control_ata_feature() sets / clears the ATA_DFLAG_CDL_ENABLED
flag during the translation of MODE SELECT to SET FEATURES. If SET FEATURES
gets deferred due to outstanding NCQ commands, the original MODE SELECT
command will be re-queued. When the re-queued MODE SELECT goes through
the ata_mselect_control_ata_feature() translation again, SET FEATURES
will not be issued because ATA_DFLAG_CDL_ENABLED has been already set or
cleared by the initial translation of MODE SELECT.
The ATA_DFLAG_CDL_ENABLED checks in ata_mselect_control_ata_feature()
are safe to remove because scsi_cdl_enable() implements a similar logic
that avoids enabling CDL if it has been enabled already.
Fixes: 17e897a45675 ("ata: libata-scsi: Improve CDL control")
Cc: stable@vger.kernel.org
Signed-off-by: Igor Pylypiv <ipylypiv@google.com>
Reviewed-by: Niklas Cassel <cassel@kernel.org>
Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
Starting with Rust 1.88.0 (released 2025-06-26), `rustdoc` complains
about a target modifier mismatch in configurations where `-Zfixed-x18`
is passed:
error: mixing `-Zfixed-x18` will cause an ABI mismatch in crate `rust_out`
|
= help: the `-Zfixed-x18` flag modifies the ABI so Rust crates compiled with different values of this flag cannot be used together safely
= note: unset `-Zfixed-x18` in this crate is incompatible with `-Zfixed-x18=` in dependency `core`
= help: set `-Zfixed-x18=` in this crate or unset `-Zfixed-x18` in `core`
= help: if you are sure this will not cause problems, you may use `-Cunsafe-allow-abi-mismatch=fixed-x18` to silence this error
The reason is that `rustdoc` was not passing the target modifiers when
configuring the session options, and thus it would report a mismatch
that did not exist as soon as a target modifier is used in a dependency.
We did not notice it in the kernel until now because `-Zfixed-x18` has
been a target modifier only since 1.88.0 (and it is the only one we use
so far).
The issue has been reported upstream [1] and a fix has been submitted
[2], including a test similar to the kernel case.
[ This is now fixed upstream (thanks Guillaume for the quick review),
so it will be fixed in Rust 1.90.0 (expected 2025-09-18).
- Miguel ]
Meanwhile, conditionally pass `-Cunsafe-allow-abi-mismatch=fixed-x18`
to workaround the issue on our side.
Cc: stable@vger.kernel.org # Needed in 6.12.y and later (Rust is pinned in older LTSs).
Reported-by: Konrad Dybcio <konrad.dybcio@oss.qualcomm.com>
Closes: https://lore.kernel.org/rust-for-linux/36cdc798-524f-4910-8b77-d7b9fac08d77@oss.qualcomm.com/
Link: https://github.com/rust-lang/rust/issues/144521 [1]
Link: https://github.com/rust-lang/rust/pull/144523 [2]
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/r/20250727092317.2930617-1-ojeda@kernel.org
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Futex hash allocations are done in mm_init() and the cleanup happens in
__mmput(). That works most of the time, but there are mm instances which
are instantiated via mm_alloc() and freed via mmdrop(), which causes the
futex hash to be leaked.
Move the cleanup to __mmdrop().
Fixes: 56180dd20c19 ("futex: Use RCU-based per-CPU reference counting instead of rcuref_t")
Reported-by: André Draszik <andre.draszik@linaro.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: André Draszik <andre.draszik@linaro.org>
Link: https://lore.kernel.org/all/87ldo5ihu0.ffs@tglx
Closes: https://lore.kernel.org/all/0c8cc83bb73abf080faf584f319008b67d0931db.camel@linaro.org
Currently, when a Secure TSC enabled SNP guest attempts to write to the
intercepted GUEST_TSC_FREQ MSR (a read-only MSR), the guest kernel response
incorrectly implies a VMM configuration error, when in fact it is the usual
VMM configuration to intercept writes to read-only MSRs, unless explicitly
documented.
Modify the intercepted TSC MSR #VC handling:
* Write to GUEST_TSC_FREQ will generate a #GP instead of terminating the
guest
* Write to MSR_IA32_TSC will generate a #GP instead of silently ignoring it
However, continue to terminate the guest when reading from intercepted
GUEST_TSC_FREQ MSR with Secure TSC enabled, as intercepted reads indicate an
improper VMM configuration for Secure TSC enabled SNP guests.
[ bp: simplify comment. ]
Fixes: 38cc6495cdec ("x86/sev: Prevent GUEST_TSC_FREQ MSR interception for Secure TSC enabled guests")
Suggested-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Nikunj A Dadhania <nikunj@amd.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com>
Link: https://lore.kernel.org/20250722074853.22253-1-nikunj@amd.com
Pull drm fixes from Dave Airlie:
"Relatively quiet week, usual amdgpu/i915/xe fixes along with a set of
fixes for fbdev format info, which fix some regressions seen in with
rc1.
bridge:
- fix OF-node leak
- fix documentation
fbdev-emulation:
- pass correct format info to drm_helper_mode_fill_fb_struct()
panfrost:
- print correct RSS size
amdgpu:
- PSP fix
- VRAM reservation fix
- CSA fix
- Process kill fix
i915:
- Fix the implementation of wa_18038517565 [fbc]
- Do not trigger Frame Change events from frontbuffer flush [psr]
xe:
- Some more xe_migrate_access_memory fixes (Auld)
- Defer buffer object shrinker write-backs and GPU waits (Thomas)
- HWMON fix for clamping limits (Karthik)
- SRIOV-PF: Set VF LMEM BAR size (Michal)"
* tag 'drm-fixes-2025-08-16' of https://gitlab.freedesktop.org/drm/kernel:
drm/xe/pf: Set VF LMEM BAR size
drm/amdgpu: fix task hang from failed job submission during process kill
drm/amdgpu: fix incorrect vm flags to map bo
drm/amdgpu: fix vram reservation issue
drm/amdgpu: Add PSP fw version check for fw reserve GFX command
drm/xe/hwmon: Add SW clamp for power limits writes
drm/xe: Defer buffer object shrinker write-backs and GPU waits
drm/xe/migrate: prevent potential UAF
drm/xe/migrate: don't overflow max copy size
drm/xe/migrate: prevent infinite recursion
drm/i915/psr: Do not trigger Frame Change events from frontbuffer flush
drm/i915/fbc: fix the implementation of wa_18038517565
drm/panfrost: Print RSS for tiler heap BO's in debugfs GEMS file
drm/radeon: Pass along the format info from .fb_create() to drm_helper_mode_fill_fb_struct()
drm/nouveau: Pass along the format info from .fb_create() to drm_helper_mode_fill_fb_struct()
drm/omap: Pass along the format info from .fb_create() to drm_helper_mode_fill_fb_struct()
drm/bridge: document HDMI CEC callbacks
drm/bridge: Describe the newly introduced drm_connector parameter for drm_bridge_detect
drm/bridge: fix OF node leak
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