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1,482,976 commits

Author SHA1 Message Date
Myeonghun Pak
762137ff74 ptp: fc3: register PTP clock after initialization
ptp_clock_register() exposes the clock to userspace. If either following
initialization operation fails, probe returns and devres frees idtfc3 while
the registered clock still refers to the clock information embedded in it.

Complete the fallible initialization before registering the clock. Schedule
the worker after registration because it requires the registered clock.
This removes post-registration failures and avoids exposing a partially
initialized clock.

Cc: stable+noautosel@kernel.org # untested fix to a driver init path race
Co-developed-by: Ijae Kim <ae878000@gmail.com>
Signed-off-by: Ijae Kim <ae878000@gmail.com>
Signed-off-by: Myeonghun Pak <mhun512@gmail.com>
Link: https://patch.msgid.link/20260803135942.48383-1-mhun512@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-06 08:15:43 -07:00
Meghana Malladi
197df050a1 arm64: dts: ti: k3-am64: Fix MDIO clock reference for ICSSG0 node
MDIO clock index changed from 62:3 to 81:0 to match proper clock
definition in the SoC device tree. Clock Id 81:0 belongs to ICSSG0
core clock, where as 62 belongs to EQEP2 device.

See: https://software-dl.ti.com/tisci/esd/latest/5_soc_doc/am64x/clocks.html

Fixes: c9087e3898 ("arm64: dts: ti: k3-am64-main: Add ICSSG nodes")
Signed-off-by: Meghana Malladi <m-malladi@ti.com>
Link: https://patch.msgid.link/20260706092229.82674-1-m-malladi@ti.com
Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>
2026-08-06 20:42:25 +05:30
Łukasz Patron
7fc1c937b6 net: qrtr: ns: Raise lookup limit to 128
Current limit of 64 is not enough for Sony Xperia 10 VII (SM6475).

After merging v6.6.142 into a downstream AOSP device, it's stuck on
boot animation and following log spam can be observed in dmesg:

E qrtr    : ctrl_cmd_new_lookup(): QRTR client node exceeds max lookup limit!
E qrtr    : qrtr_ns_worker(): failed while handling packet from 1:16600

No idea why it needs more than 64 client lookups, but it appears to
work fine with 128 as it did when there were no limits.

I don't really have a good way to investigate what it needs all
these lookups for as most of the userspace is closed source.

Fixes: 5640227d9a ("net: qrtr: ns: Limit the maximum number of lookups")
Signed-off-by: Łukasz Patron <priv.luk@gmail.com>
Link: https://patch.msgid.link/20260804201919.1148015-1-priv.luk@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-06 08:10:44 -07:00
Takashi Iwai
2a611c4a1c ALSA: hda: cix-ipbloq: Avoid build with 32bit archs
The cix-ipbloq driver has an assumption of 64bit DMA address, and
building it for 32bit dma_addr_t leads to a sparse / compile warning.
Simply disable the builds for 32bit archs for avoiding such reports.

Fixes: d91e9bd101 ("ALSA: hda: add CIX IPBLOQ HDA controller support")
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202608061559.Kxqvi5LZ-lkp@intel.com/
Link: https://patch.msgid.link/20260806104431.1300304-1-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2026-08-06 17:02:38 +02:00
Takashi Iwai
9c04742e73 ALSA: rawmidi: Work around false-positive mutex lockdep warning
When opening a legacy rawmidi device for a UMP, it may re-open an
existing rawmidi device for appending to a substream, leading to a
lockdep warning due to rmidi->open_mutex taken twice -- but the
rawmidi devices are completely individual, hence it's a
false-positive.

For avoiding the warning, modify the helper to open a rawmidi instance
with a proper locking subclass from the UMP legacy open.

Unfortunately, there is no good way to achieve it with guard(), so
reverted to the manual mutex calls again.

Reported-by: syzbot+d10d58fc99caa0489796@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/6a6a9634.57649fcc.360844.000b.GAE@google.com
Link: https://patch.msgid.link/20260806101352.1291581-1-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2026-08-06 17:02:22 +02:00
Takashi Iwai
02442d5fe8 ALSA: dummy: Check card index validity at probe
snd_dummy_probe() blindly trusts that the given devptr->id value is
within the proper card index range.  It's OK for the devices the
driver itself creates at the module probe time, but if the device is
bound manually via sysfs interface, this could be -1 as "none", and
this leads to OOB access for index[] and other parameters.

Add a sanity check for the card index and warn/correct it if it's a
value out of the range.

Reported-by: syzbot+2fb5d1f7cc4c1f132bcc@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/6a73bd4d.01d0871a.3a0d52.0005.GAE@google.com
Cc: <stable@vger.kernel.org>
Link: https://patch.msgid.link/20260806100433.1287393-1-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2026-08-06 17:02:02 +02:00
Paolo Bonzini
1d78d33275 KVM: SVM: Serialize accesses to the owner and mirror list with separate lock
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>
2026-08-06 16:50:02 +02:00
Alessio Belle
559b757a71 drm/imagination: Fix repeated typo in KCCB documentation
Fix sent -> send in the documentation for all variants of
pvr_kccb_send_cmd*().

Signed-off-by: Luigi Santivetti <luigi.santivetti@imgtec.com>
Reviewed-by: Alexandru Dadu <alexandru.dadu@imgtec.com>
Link: https://patch.msgid.link/20260804-staging-pvr-docs-fixes-v2-3-a5a9569a1c1d@imgtec.com
Signed-off-by: Alessio Belle <alessio.belle@imgtec.com>
2026-08-06 15:49:09 +01:00
Alexandru Dadu
62481fecc3 drm/imagination: Update Rogue heap comments
Update Rogue heap memory comments to fix typos.

Signed-off-by: Alexandru Dadu <alexandru.dadu@imgtec.com>
Signed-off-by: Luigi Santivetti <luigi.santivetti@imgtec.com>
Reviewed-by: Alessio Belle <alessio.belle@imgtec.com>
Link: https://patch.msgid.link/20260804-staging-pvr-docs-fixes-v2-2-a5a9569a1c1d@imgtec.com
Signed-off-by: Alessio Belle <alessio.belle@imgtec.com>
2026-08-06 15:49:09 +01:00
Matt Coster
11bc94f80a drm/imagination: fixup some docs in pvr_gem.h
Update and remove some old comment in the PVR GEM documentation.

Signed-off-by: Matt Coster <matt.coster@imgtec.com>
Signed-off-by: Luigi Santivetti <luigi.santivetti@imgtec.com>
Reviewed-by: Alessio Belle <alessio.belle@imgtec.com>
Link: https://patch.msgid.link/20260804-staging-pvr-docs-fixes-v2-1-a5a9569a1c1d@imgtec.com
Signed-off-by: Alessio Belle <alessio.belle@imgtec.com>
2026-08-06 15:49:09 +01:00
Jiacheng Yu
3dfaae0424 params: fix charp corruption on allocation failure
param_set_charp() stores charp parameters in allocated memory after slab is
available, and releases the previous value when the parameter is updated.

The previous value is released before the replacement allocation succeeds.
If kmalloc_parameter() fails, the setter returns -ENOMEM with the parameter
left as NULL.

Failing zswap's compressor update before zswap is initialized can later
trigger:

  BUG: kernel NULL pointer dereference, address: 0000000000000000
  RIP: 0010:strcmp+0x10/0x30
  Call Trace:
    zswap_setup+0x3b1/0x490
    zswap_enabled_param_set+0x5b/0xa0
    param_attr_store+0x93/0xe0
    module_attr_store+0x1c/0x30
    kernfs_fop_write_iter+0x116/0x1f0

Allocate and copy the replacement first, then replace the parameter value
only after allocation succeeds.

Fixes: e180a6b775 ("param: fix charp parameters set via sysfs")
Cc: stable@vger.kernel.org
Signed-off-by: Jiacheng Yu <yujiacheng3@huawei.com>
Reviewed-by: Petr Pavlu <petr.pavlu@suse.com>
Signed-off-by: Petr Pavlu <petr.pavlu@suse.com>
2026-08-06 16:44:48 +02:00
Thiébaud Weksteen
9a5ff45689 module: validate string table section types
In elf_validity_cache_sechdrs, section sizes and offsets are validated,
unless the section type is SHT_NULL or SHT_NOBITS.

Later, elf_validity_cache_secstrings and elf_validity_cache_index_str
access the section name table (.shstrtab) and symbol string table
(.strtab) headers without first ensuring that their types are
SHT_STRTAB. If a section type is SHT_NULL or SHT_NOBITS, sh_offset has
not been validated and may reference out-of-bounds memory when
dereferenced in elf_validity_cache_secstrings or
elf_validity_cache_strtab.

Validate that both string section headers are of type SHT_STRTAB before
caching them.

Cc: stable@vger.kernel.org
Signed-off-by: Thiébaud Weksteen <tweek@google.com>
Reviewed-by: Aaron Tomlin <atomlin@atomlin.com>
Reviewed-by: Petr Pavlu <petr.pavlu@suse.com>
Signed-off-by: Petr Pavlu <petr.pavlu@suse.com>
2026-08-06 16:44:45 +02:00
Kathiravan Thirumoorthy
4496593f4d dt-bindings: mfd: qcom,tcsr: Document the IPQ9650 TCSR block
Document the TCSR block found on the Qualcomm's IPQ9650 SoC.

Signed-off-by: Kathiravan Thirumoorthy <kathiravan.thirumoorthy@oss.qualcomm.com>
Acked-by: Rob Herring (Arm) <robh@kernel.org>
Link: https://patch.msgid.link/20260727-ipq9650_tcsr_binding-v1-1-931ac0e056d0@oss.qualcomm.com
Signed-off-by: Lee Jones <lee@kernel.org>
2026-08-06 15:41:44 +01:00
Junzhe Yu
8f3901fbb4 ext4: guard against NULL s_group_info in ext4_get_group_info
Resend: previous attempt was rejected by vger for containing HTML.

==================================================================

ext4_mark_group_bitmap_corrupted() already treats a NULL return from
ext4_get_group_info() as "nothing to do", but ext4_get_group_info()
indexes s_group_info without checking whether the array exists.

During mount, fast-commit replay runs inside jbd2_journal_load() from
ext4_load_and_init_journal(), which is before ext4_mb_init() allocates
s_group_info. Replaying an FC UNLINK for an inode whose bitmap bit is
already clear takes:

   ext4_fc_replay_unlink -> iput -> ext4_evict_inode -> ext4_free_inode
     -> ext4_mark_group_bitmap_corrupted -> ext4_get_group_info

and faults on the NULL s_group_info base. Userspace only mounts a dirty
ext4 image; this is a supported recovery path.

Return NULL when s_group_info (or the per-block grp_info row) is unset
so the existing caller check is effective during early mount.

Tested on Linux v6.6.145 KASAN: crafted FC-unlink image previously
triggered KASAN null-ptr-deref / panic in ext4_get_group_info; with this
patch, mount succeeds (EXT4 "bit already cleared" may still log). Also
observed on v6.6.144; still present on torvalds/linux as of
f5098b6bae (2026-07-26).

A self-contained Docker/QEMU reproducer (craft + mount + patch verify) is
available on request.

Signed-off-by: Yu Junzhe <junzheyu1@gmail.com>
Link: https://patch.msgid.link/65c955b0-716b-4599-b925-59c2782e38b4@gmail.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2026-08-06 10:34:27 -04:00
Jan Kara
5aa98f874c ext4: fix spurious message about orphan cleanup on RO fs
When orphan_file feature is enabled, ext4_orphan_cleanup() was always
walking through the orphan file looking for orphan inodes. This is
mostly harmless but for read-only filesystem it results in spurious
"orphan cleanup on readonly fs" message and in other cornercases it
could result in similar somewhat misleading messages. Skip orphan
cleanup if the orphan file is empty to avoid confusing messages.

Fixes: 02f310fcf4 ("ext4: Speedup ext4 orphan inode handling")
Reported-by: Tigran Aivazian <aivazian.tigran@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Reviewed-by: Baokun Li <libaokun@linux.alibaba.com>
Link: https://patch.msgid.link/20260803160037.64285-2-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2026-08-06 10:24:31 -04:00
Matthias Goergens
54b6bd4089 ext4: stop retrying saturated xattr cache entries
ext4_xattr_block_set() retries when a cache entry selected for reuse
has a saturated reference count after taking the buffer lock. The retry
returns to the mbcache lookup without making that entry ineligible, so
it can select the same unusable entry indefinitely. A task spinning
there can hold the parent directory's i_rwsem and leave concurrent
rmdir callers blocked.

Normally a reusable entry has a reference count below
EXT4_XATTR_REFCOUNT_MAX because the count and MBE_REUSABLE_B are
updated under the same buffer lock. A corrupted filesystem can violate
that invariant. The syzbot reproducer reports allocator and xattr
corruption before triggering this retry loop.

Check the untrusted on-disk count before incrementing it, avoiding
overflow, and clear MBE_REUSABLE_B when it is already saturated. The
next lookup then skips the entry that was just proven unusable. This
mirrors the normal transition at EXT4_XATTR_REFCOUNT_MAX; the release
path marks the entry reusable again on the exact 1024-to-1023
transition.

Using the same QEMU harness and guest parameters, current unpatched
Linux hung in 6 of 8 420-second trials with the do_rmdir signature;
representative NMI backtraces caught the owner spinning in
ext4_xattr_block_set(). The patched kernel completed 28 of 28 trials
without a hung-task report; the final twelve trials exercised the
reviewed overflow-safe form of the change. syzbot's patch testing also
completed without reproducing the hang.

Reported-and-tested-by: syzbot+e68dbebd9617a9250e8d@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=e68dbebd9617a9250e8d
Fixes: 65f8b80053 ("ext4: fix race when reusing xattr blocks")
Cc: stable@vger.kernel.org
Signed-off-by: Matthias Goergens <matthias.goergens@gmail.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reported-by: syzbot+e68dbebd9617a9250e8d@syzkaller.appspotmail.com
Tested-by: syzbot+e68dbebd9617a9250e8d@syzkaller.appspotmail.com
Link: https://patch.msgid.link/20260802065941.1726052-1-matthias.goergens@gmail.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2026-08-06 10:23:48 -04:00
Eric Biggers
da32af420d ext4: don't enable DAX on new encrypted files
Currently, when a new encrypted regular file is created, the call to
ext4_set_inode_flags(inode, init=true) in __ext4_new_inode() is made
before EXT4_INODE_ENCRYPT is set.  As a result, it can set S_DAX if the
filesystem is mounted with "-o dax=always".

EXT4_INODE_ENCRYPT then actually gets set a bit later in
__ext4_new_inode(), when it calls fscrypt_set_context() which calls
ext4_set_context().  ext4_set_context() sets EXT4_INODE_ENCRYPT and
calls ext4_set_inode_flags(inode, init=false) to set S_ENCRYPTED too.

This was intended to clear S_DAX as well.  However, this was broken by
commit 043546e46d ("fs/ext4: Only change S_DAX on inode load").  This
causes data written to the file to bypass encryption, also causing
xfstests failures such as generic/548 (when "-o dax=always" is used).

Fix this by simplifying the flow by making __ext4_new_inode() set
EXT4_INODE_ENCRYPT earlier.  This makes it take effect in
ext4_set_inode_flags(inode, init=true), making S_DAX never be set.

Similarly, make EXT4_STATE_MAY_INLINE_DATA never be set in the first
place on new encrypted inodes.  Then it doesn't need to be cleared.

As a result of these simplifications, ext4_set_context() no longer needs
to change inode flags or state when 'handle != NULL'.  Remove that too.

Reported-by: Disha Goel <disgoel@linux.ibm.com>
Reported-by: Ojaswin Mujoo <ojaswin@linux.ibm.com>
Closes: https://lore.kernel.org/r/20260723085648.1500357-1-ojaswin@linux.ibm.com
Fixes: 043546e46d ("fs/ext4: Only change S_DAX on inode load")
Cc: stable@vger.kernel.org
Signed-off-by: Eric Biggers <ebiggers@kernel.org>
Tested-by: Disha Goel <disgoel@linux.ibm.com>
Reviewed-by: Ojaswin Mujoo <ojaswin@linux.ibm.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://patch.msgid.link/20260730175212.36923-1-ebiggers@kernel.org
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2026-08-06 10:21:52 -04:00
Ninad Naik
e36f882561 dt-bindings: leds: lacie,ns2-leds: Convert to DT schema
Convert lacie,ns2-leds to DT schema.

Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@oss.qualcomm.com>
Signed-off-by: Ninad Naik <ninadnaik07@gmail.com>
Closes: https://lore.kernel.org/r/202607231542.6ovJrInT-lkp@intel.com/
Link: https://patch.msgid.link/20260728183945.12008-1-ninadnaik07@gmail.com
Signed-off-by: Lee Jones <lee@kernel.org>
2026-08-06 15:19:36 +01:00
Heiko Carstens
30df3ab3c9 s390/block: Enable CONTEXT_ANALYSIS
All drivers in drivers/s390/block pass clang's compile time context
analysis. Therefore enable CONTEXT_ANALYSIS.

Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Acked-by: Stefan Haberland <sth@linux.ibm.com>
Link: https://patch.msgid.link/20260806130050.2057443-3-hca@linux.ibm.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2026-08-06 08:14:13 -06:00
Heiko Carstens
11d4f5e69f s390/dasd: Add __context_unsafe() attribute to various functions
Disable context analysis for various functions to get rid of context
analysis compile time warnings using clang caused by conditional
locking like e.g.:

drivers/s390/block/dasd_eckd.c:1462:3:
  warning: releasing mutex 'dasd_pe_handler_mutex' that was not held [-Wthread-safety-analysis]
 1462 |                 mutex_unlock(&dasd_pe_handler_mutex);
      |                 ^

Use __context_unsafe() to provide a short comment why context analysis is
disabled for each function. It doesn't look like those functions can be
easily reworked to get rid of conditional locking.
Therefore disable context analysis for (only) those functions.

Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Acked-by: Stefan Haberland <sth@linux.ibm.com>
Link: https://patch.msgid.link/20260806130050.2057443-2-hca@linux.ibm.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2026-08-06 08:14:13 -06:00
Loic Poulain
cd5d8dcd4a leds: pca963x: Add multicolor LED class support
Allow grouping of individual PCA963x PWM channels into a single
multicolor LED device by adding support for the LED multicolor class.

A child node with sub-children is treated as a multicolor group,
others are treated as single leds, keeping full backwards compatibility.

Signed-off-by: Loic Poulain <loic.poulain@oss.qualcomm.com>
Link: https://patch.msgid.link/20260727-monza-leds-v8-3-6e7e93d44dba@oss.qualcomm.com
Signed-off-by: Lee Jones <lee@kernel.org>
2026-08-06 15:13:41 +01:00
Loic Poulain
160c78e69c dt-bindings: leds: nxp,pca963x: Add multicolor LED support
Add support for grouping individual PCA963x channels into a multicolor
LED by introducing a multi-led@N node pattern. This follows the
convention established by other multicolor LED drivers such as
kinetic,ktd202x.

This is necessary to support and model hardware setups where multiple
PWM channels drive a single physical RGB LED.

Acked-by: Conor Dooley <conor.dooley@microchip.com>
Signed-off-by: Loic Poulain <loic.poulain@oss.qualcomm.com>
Link: https://patch.msgid.link/20260727-monza-leds-v8-2-6e7e93d44dba@oss.qualcomm.com
Signed-off-by: Lee Jones <lee@kernel.org>
2026-08-06 15:13:24 +01:00
Loic Poulain
b765b508bd dt-bindings: leds: nxp,pca963x: Fix reg maximum for pca9635
The pca9635 supports 16 LED channels, unlike the pca9634 which only
supports 8. The allOf conditional grouped both chips under a single
else branch capping reg at a maximum of 7.

Give pca9634 its own if/then block and set maximum: 15 unconditionally
in the top-level led@ node, making it the default for pca9635 and any
future compatible. Also tighten the node name regex from [0-9a-f]+ to
[0-9a-f] to match the single-digit hardware limit.

Acked-by: Conor Dooley <conor.dooley@microchip.com>
Signed-off-by: Loic Poulain <loic.poulain@oss.qualcomm.com>
Link: https://patch.msgid.link/20260727-monza-leds-v8-1-6e7e93d44dba@oss.qualcomm.com
Signed-off-by: Lee Jones <lee@kernel.org>
2026-08-06 15:13:15 +01:00
Danilo Krummrich
f88db65aec rust: io: gate ioremap doctests on CONFIG_HAS_IOMEM
The doc examples in io.rs and devres.rs directly call
bindings::ioremap() and bindings::iounmap(), which do not exist when
CONFIG_HAS_IOMEM is not set. This causes build failures with
CONFIG_RUST_KERNEL_DOCTESTS=y on such configurations (e.g. s390
allnoconfig).

Gate the affected doctests with `#![cfg(CONFIG_HAS_IOMEM)]` so they are
skipped when IOMEM is unavailable.

Fixes: 3f70ebe638 ("s390: Enable Rust support")
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Link: https://patch.msgid.link/20260805212920.1996937-2-dakr@kernel.org
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
2026-08-06 16:05:50 +02:00
Danilo Krummrich
4f5f23846d rust: io: gate ioremap/iounmap on CONFIG_HAS_IOMEM
s390 does not provide ioremap()/iounmap() when CONFIG_HAS_IOMEM is not
set (which requires CONFIG_PCI on that architecture). This causes a
build failure with Rust enabled on e.g. s390 allnoconfig:

	In file included from rust/helpers/helpers.c:68:
	rust/helpers/io.c:8:9: error: call to undeclared function 'ioremap'; ISO C99 and later do not support implicit function declarations
	      [-Wimplicit-function-declaration]
	    8 |         return ioremap(offset, size);
	      |                ^
	rust/helpers/io.c:19:2: error: call to undeclared function 'iounmap'; ISO C99 and later do not support implicit function declarations
	      [-Wimplicit-function-declaration]
	   19 |         iounmap(addr);

Guard the C helpers behind #ifdef CONFIG_HAS_IOMEM and cfg-gate the Rust
io::mem module, such that IoMem, ExclusiveIoMem and IoRequest are not
available without CONFIG_HAS_IOMEM.

Note that the C API is inconsistent about this. For instance,
devm_ioremap() has no stub and produces a link failure without
CONFIG_HAS_IOMEM, whereas devm_platform_ioremap_resource() provides an
inline stub returning -EINVAL.

The approach taken here (compile-time gating) matches the former, which
is slightly more appropriate since any driver performing MMIO currently
requires CONFIG_HAS_IOMEM.

Ideally, s390 should provide ioremap()/iounmap() stubs unconditionally
(as UML already does), removing the need for any config gating as
discussed in [1]; a follow-up patch for s390 is expected.

Cc: Arnd Bergmann <arnd@arndb.de>
Reported-by: Miguel Ojeda <ojeda@kernel.org>
Closes: https://lore.kernel.org/all/20260803180931.97202-1-ojeda@kernel.org [1]
Fixes: 3f70ebe638 ("s390: Enable Rust support")
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Link: https://patch.msgid.link/20260805212920.1996937-1-dakr@kernel.org
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
2026-08-06 16:05:50 +02:00
Bhawanpreet Lakha
be784e161a drm/amd/display: Add KUnit tests for crtc set_static_screen_optimze
Add dm_test_crtc_set_static_screen_optimze_sr_entry_psr and
dm_test_crtc_set_static_screen_optimze_psr_su_skips to cover the
allow_sr_entry == true path of amdgpu_dm_crtc_set_static_screen_optimze():
the replay/PSR event updates when psr_version < DC_PSR_VERSION_SU_1, and
skipping the PSR event update when psr_version is DC_PSR_VERSION_SU_1.

Assisted-by: Copilot:Claude-Opus-4.8
Reviewed-by: Alex Hung <alex.hung@amd.com>
Signed-off-by: Bhawanpreet Lakha <bhawanpreet.lakha@amd.com>
Signed-off-by: Roman Li <roman.li@amd.com>
Tested-by: Dan Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2026-08-06 09:59:11 -04:00
Bhawanpreet Lakha
466a270202 drm/amd/display: Add KUnit tests for crtc set_vupdate_irq
Add dm_test_crtc_set_vupdate_irq_dc_busy and
dm_test_crtc_set_vupdate_irq_enable to cover the previously untested
paths in amdgpu_dm_crtc_set_vupdate_irq() where an OTG instance is
assigned: dc_interrupt_set() failing (returns -EBUSY) and succeeding
via a mock IRQ service (returns 0 for enable and disable).

Assisted-by: Copilot:Claude-Opus-4.8
Reviewed-by: Alex Hung <alex.hung@amd.com>
Signed-off-by: Bhawanpreet Lakha <bhawanpreet.lakha@amd.com>
Signed-off-by: Roman Li <roman.li@amd.com>
Tested-by: Dan Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2026-08-06 09:59:05 -04:00
Bhawanpreet Lakha
ae980af4f6 drm/amd/display: Add KUnit test for crtc vblank event completion
Add dm_test_crtc_handle_vblank_completes_cursor_only to cover the
previously untested branch in amdgpu_dm_crtc_handle_vblank() where a
pending event with pflip_status != AMDGPU_FLIP_SUBMITTED (a cursor-only
commit) is signalled: the vblank event is sent, the vblank reference is
dropped, and acrtc->event is cleared.

Assisted-by: Copilot:Claude-Opus-4.8
Reviewed-by: Alex Hung <alex.hung@amd.com>
Signed-off-by: Bhawanpreet Lakha <bhawanpreet.lakha@amd.com>
Signed-off-by: Roman Li <roman.li@amd.com>
Tested-by: Dan Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2026-08-06 09:59:01 -04:00
Bhawanpreet Lakha
5eccb2c27b drm/amd/display: Add active plane count tests for crtc
Expose amdgpu_dm_crtc_count_crtc_active_planes() for KUnit and add tests
covering the empty plane list and the mixed case exercising the mask
filter, cursor skip, missing plane state, and framebuffer presence
branches.

Assisted-by: Copilot:Claude-Opus-4.8
Reviewed-by: Alex Hung <alex.hung@amd.com>
Signed-off-by: Bhawanpreet Lakha <bhawanpreet.lakha@amd.com>
Signed-off-by: Roman Li <roman.li@amd.com>
Tested-by: Dan Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2026-08-06 09:58:58 -04:00
Bhawanpreet Lakha
7d52e9cf80 drm/amd/display: Add idle worker tests for crtc
Expose amdgpu_dm_idle_worker() for KUnit and add tests covering the
disabled exit, both loop break paths, and the enable-body path. Add
dm_kunit_alloc_dc_state() and dm_kunit_alloc_clk_mgr() helpers to
support the new tests.

Assisted-by: Copilot:Claude-Opus-4.8
Reviewed-by: Alex Hung <alex.hung@amd.com>
Signed-off-by: Bhawanpreet Lakha <bhawanpreet.lakha@amd.com>
Signed-off-by: Roman Li <roman.li@amd.com>
Tested-by: Dan Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2026-08-06 09:58:54 -04:00
Bhawanpreet Lakha
bed804fe0b drm/amd/display: Add vblank handling tests for crtc
Add KUnit coverage for the CRTC vblank paths:

- amdgpu_dm_crtc_handle_vblank: no-event completion and the
  AMDGPU_FLIP_SUBMITTED guard that keeps a pending event pending.
- amdgpu_dm_crtc_vblank_control_worker: enable increments, disable
  decrements, and disable clamps the active vblank IRQ count at zero.
- amdgpu_dm_crtc_disable_vblank: disable path returns cleanly when the
  IRQ subsystem is not installed.

Expose amdgpu_dm_crtc_vblank_control_worker for KUnit via
STATIC_IFN_KUNIT/EXPORT_IF_KUNIT and declare it in the header.

Assisted-by: Copilot:Claude-Opus-4.8
Reviewed-by: Alex Hung <alex.hung@amd.com>
Signed-off-by: Bhawanpreet Lakha <bhawanpreet.lakha@amd.com>
Signed-off-by: Roman Li <roman.li@amd.com>
Tested-by: Dan Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2026-08-06 09:58:51 -04:00
Bhawanpreet Lakha
d1db1a99fc drm/amd/display: Add KUnit tests for more crtc functions
Expand KUnit coverage for amdgpu_dm_crtc.c with tests for functions that
are easy to exercise in isolation:

- amdgpu_dm_crtc_set_static_screen_optimze(): the !allow_sr_entry early
  return.
- amdgpu_dm_crtc_enable_vblank(): rejection with -EINVAL when enabling
  vblank on an unconfigured CRTC.
- amdgpu_dm_crtc_update_crtc_active_planes(): the no-stream branch that
  resets active_planes to zero.
- amdgpu_dm_crtc_duplicate_state(): DM-specific fields are carried over.
- amdgpu_dm_crtc_reset_state(): a fresh state is allocated and installed.
- amdgpu_dm_crtc_destroy_state(): a stream-less state is freed cleanly.

Expose amdgpu_dm_crtc_destroy_state(), amdgpu_dm_crtc_duplicate_state(),
amdgpu_dm_crtc_reset_state() and amdgpu_dm_crtc_update_crtc_active_planes()
to the tests via STATIC_IFN_KUNIT/EXPORT_IF_KUNIT.

Assisted-by: Copilot:Claude-Opus-4.8
Reviewed-by: Alex Hung <alex.hung@amd.com>
Signed-off-by: Bhawanpreet Lakha <bhawanpreet.lakha@amd.com>
Signed-off-by: Roman Li <roman.li@amd.com>
Tested-by: Dan Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2026-08-06 09:58:47 -04:00
Karthi Kandasamy
73efd24e21 drm/amd/display: Fix seamless mode switch not triggering for HDR to SDR transition
[Why]
The seamless mode switch was not getting triggered during HDR to SDR
transitions, and no DPCD write was observed. Root cause analysis
revealed that incorrect panel capabilities were being reported for PSR
SU panels. Due to the wrong capabilities, the OS was not invoking the
seamless mode switch API, resulting in no DPCD communication and also
gated eDP teardown across the seamless mode switch hold.

[How]
Fixed by setting the correct power panel capabilities for PSR SU panels.
This ensures the OS receives accurate panel capability information and
triggers the seamless mode switch API as expected, restoring proper
DPCD writes during HDR to SDR transitions.
The DC commit sequence was tearing the eDP down anyway -- backlight off,
ABM disable, DPMS off, PSR/Replay enable state cleared, PHY TX off,
OTG/OPTC off; all these actions are blocked now with the
skip_implict_edp_power_control

Reviewed-by: Aric Cyr <aric.cyr@amd.com>
Signed-off-by: Karthi Kandasamy <karthi.kandasamy@amd.com>
Signed-off-by: Roman Li <roman.li@amd.com>
Tested-by: Dan Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2026-08-06 09:58:41 -04:00
Alex Hung
8b87300e1b drm/amd/display: Fix wb_info leak and NULL deref in writeback
[WHAT]
dc_stream_add_writeback() copies wb_info by value, so free it on all
paths via a single cleanup label. Also bail out early when no pipe_ctx
matches the stream to avoid a NULL pointer dereference.

Assisted-by: Copilot:Claude-Opus-4.8
Reviewed-by: Harry Wentland <harry.wentland@amd.com>
Signed-off-by: Alex Hung <alex.hung@amd.com>
Signed-off-by: Roman Li <roman.li@amd.com>
Tested-by: Dan Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2026-08-06 09:58:35 -04:00
Fangzhi Zuo
df94112cee drm/amd/display: Gate HDMI FRL status polling on active FRL link rate
[Why]
hdmi_frl_status_polling_work() skipped any link whose connector_signal
was not SIGNAL_TYPE_HDMI_FRL. connector_signal is not reliably set to
SIGNAL_TYPE_HDMI_FRL while a link is actually running FRL, so links that
were operating in FRL mode were skipped and their status flags never got
polled, missing link-retrain events.

[How]
Use frl_link_settings.frl_link_rate to decide whether a link is running
FRL. A non-zero rate means FRL is active, so only links with a zero rate
are skipped. This ensures every link actually operating in FRL mode is
polled for status changes.

Reviewed-by: Harry Wentland <harry.wentland@amd.com>
Signed-off-by: Fangzhi Zuo <jerry.zuo@amd.com>
Signed-off-by: Roman Li <roman.li@amd.com>
Tested-by: Dan Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2026-08-06 09:58:29 -04:00
Harry VanZyllDeJong
3df68ac6a7 drm/amd/display: Update VRR info packet to support 12-bit refresh rates
[Why]
VRR info packet previously only supported up to 10-bit refresh rate values
limiting the range of FreeSync minimum and maximum refresh rates that
could be encoded.

[How]
Expanded the bit masking in PB11/PB12 from 2 to 4 bits to capture bits
11:8 of the minimum and maximum FreeSync refresh rates, enabling the VRR
info packet to encode 12-bit refresh rate values.

Reviewed-by: Anthony Koo <anthony.koo@amd.com>
Signed-off-by: Harry VanZyllDeJong <hvanzyll@amd.com>
Signed-off-by: Roman Li <roman.li@amd.com>
Tested-by: Dan Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2026-08-06 09:58:25 -04:00
Charlene Liu
807d6345bc drm/amd/display: Ensure dtbclk is enabled
[why]
ensure dtbclk is enabled before hdmistreamclk_en

pmfw could stop dtbclk on idle.
driver needs to ensure dtbclk enabled is enabled before hdmistreamclk_en
also disable debounce timer on dcn42.

Reviewed-by: Chris Park <chris.park@amd.com>
Reviewed-by: Leo Chen <leo.chen@amd.com>
Signed-off-by: Charlene Liu <Charlene.Liu@amd.com>
Signed-off-by: Roman Li <roman.li@amd.com>
Tested-by: Dan Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2026-08-06 09:58:19 -04:00
Harry Wentland
7cc88c0d56 drm/amd/display: Bounds-check connector->index in dm_dp_mst_get_modes
dm_dp_mst_get_modes() uses drm_connector->index to index the
per-connector HDCP arrays in struct hdcp_workqueue. Those arrays are
sized to AMDGPU_DM_MAX_DISPLAY_COUNT, which matches the DRM connector
index range (0..31). Add a defensive bounds check so that, should the
DRM connector index range ever grow beyond the array size, the access
is skipped instead of reading and writing out of bounds.

Assisted-by: Copilot:claude-opus-4.8
Reviewed-by: Alex Hung <alex.hung@amd.com>
Signed-off-by: Harry Wentland <harry.wentland@amd.com>
Signed-off-by: Roman Li <roman.li@amd.com>
Tested-by: Dan Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2026-08-06 09:58:08 -04:00
Harry Wentland
261e0fe4e2 drm/amd/display: Resize MST HDCP per-connector arrays to 32
AMDGPU_DM_MAX_DISPLAY_INDEX is 31. It suggest a maximum number of
32 connectors. But the way it's used is like MAX_DISPLAY_COUNT.
Hence we're off by one with DRM core, which supports a max of 32
connectors.

Rename AMDGPU_DM_MAX_DISPLAY_INDEX to AMDGPU_DM_MAX_DISPLAY_COUNT
to match its actual use, and increase the size to 32 to match the
originally intended size.

Fixes: 82986fd631 ("drm/amd/display: save restore hdcp state when display is unplugged from mst hub")
Assisted-by: Copilot:claude-opus-4.8
Reviewed-by: Alex Hung <alex.hung@amd.com>
Signed-off-by: Harry Wentland <harry.wentland@amd.com>
Signed-off-by: Roman Li <roman.li@amd.com>
Tested-by: Dan Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2026-08-06 09:56:36 -04:00
Timur Kristóf
1edb323406 drm/amdgpu/gfx6: Fixup emit_cntxcntl()
Set bits on dword 2 like GFX7-8 except load_global_uconfig
which doesn't exist on GFX6.

Emit VS_PARTIAL_FLUSH before VGT_FLUSH like GFX7-8.

For reference see old PAL which explains the bit fields in
this register and that load_global_uconfig doesn't exist on GFX6
and also see gfx_v7_ring_emit_cntxcntl() for the GFX7 code
which this commit follows.

Fixes: 2cd46ad223 ("drm/amdgpu: add graphic pipeline implementation for si v8")
Signed-off-by: Timur Kristóf <timur.kristof@gmail.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2026-08-06 09:55:29 -04:00
Roman Li
6972f0708f drm/amd/display: Remove duplicate in tests/Makefile
The duplicate amdgpu_dm_plane_test.o entry causes linker errors
during the arm-64 build.

Reviewed-by: Wayne Lin <Wayne.Lin@amd.com>
Signed-off-by: Roman Li <roman.li@amd.com>
Tested-by: Dan Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2026-08-06 09:54:48 -04:00
Alex Deucher
0e8faef0aa drm/amdgpu/gmc12.1: fix MMHUB0 check in pasid tlb flush
Check for mmhub0 rather than mmhub1.  Looks like a copy
paste typo.

Fixes: d0c989a0aa ("drm/amd/amdgpu : Use the MES INV_TLBS API for tlb invalidation on gfx12_1")
Cc: Shaoyun Liu <shaoyun.liu@amd.com>
Reviewed-by: Shaoyun Liu <shaoyun.liu@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2026-08-06 09:53:42 -04:00
Aurabindo Pillai
992694ad28 drm/amd/display: Enable DCN6 sources compilation
- Add hooks in various entry points to perform hw/sw init for DCN6 asic
- Add dependent changes needed to enable DCN6 asic
- Update the Makefiles so that DCN6 related newly added sources are compiled

Signed-off-by: Aurabindo Pillai <aurabindo.pillai@amd.com>
Signed-off-by: Roman Li <Roman.Li@amd.com>
Reviewed-by: Ivan Lipski <ivan.lipski@amd.com>
Tested-by: Dan Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2026-08-06 09:53:32 -04:00
Steve Dunnagan
942901eeda leds: gpio: Clear error pointers for skipped LEDs
gpio_led_get_gpiod() returns an error pointer when a platform-data
LED's GPIO is unavailable. gpio_led_probe() skips registration in that
case, but leaves the error pointer in led_dat->gpiod.

The skipped entry remains included in priv->num_leds. During shutdown,
gpio_led_shutdown() walks those entries and passes the error pointer to
gpio_led_set(), producing:

  gpiod_set_value: invalid GPIO (errorpointer: -ENOENT)

Clear led_dat->gpiod before skipping the LED so skipped entries do not
retain error-valued descriptors.

Fixes: 45d4c6de4e ("leds: gpio: Try to lookup gpiod from device")
Suggested-by: Lee Jones <lee@kernel.org>
Assisted-by: ChatGPT:GPT-5.5-Thinking
Signed-off-by: Steve Dunnagan <sdunnaga@redhat.com>
Reviewed-by: Linus Walleij <linusw@kernel.org>
Link: https://patch.msgid.link/20260724180412.43150-1-sdunnaga@redhat.com
Signed-off-by: Lee Jones <lee@kernel.org>
2026-08-06 14:51:44 +01:00
Lijo Lazar
3e8e92b789 drm/amdgpu: Allocate coredump ring buffers per ring
Allocate each ring buffer separately. A single allocation summing all
ring sizes can exceed the page allocator's MAX_ORDER limit and fail;
per-ring buffers stay small enough to satisfy. The existing allocation
style doesn't capture any ring data if the huge allocation fails.
Splitting into multiple allocations helps to capture as much data as
possible for the core dump.

A failed ring is left with a NULL buffer and skipped when formatting.

Fixes: eea85914d1 ("drm/amdgpu: save ring content before resetting the device")
Signed-off-by: Lijo Lazar <lijo.lazar@amd.com>
Assisted-by: Claude Code
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2026-08-06 09:50:13 -04:00
Lijo Lazar
74d48bd6b7 drm/amdgpu: Use virtual alloc during coredump
The number of rings with outstanding fences can be large, requiring a
bigger allocation. Such allocations don't need to be physically
contiguous, so use kvzalloc/kvcalloc which fall back to vmalloc when
contiguous memory isn't available. This also matches the existing
kvfree used to free these allocations.

Also guard the allocation with ring_count to avoid passing 0 size to
allocation routines.

Fixes: eea85914d1 ("drm/amdgpu: save ring content before resetting the device")
Signed-off-by: Lijo Lazar <lijo.lazar@amd.com>
Reviewed-by: Hawking Zhang <Hawking.Zhang@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2026-08-06 09:48:34 -04:00
Aurabindo Pillai
7f7d7ea1fa drm/amd/display: Add new sources for DCN6
Add DCN6 code to DC, DML2, and DMUB

Signed-off-by: Aurabindo Pillai <aurabindo.pillai@amd.com>
Signed-off-by: Roman Li <Roman.Li@amd.com>
Reviewed-by: Ivan Lipski <ivan.lipski@amd.com>
Tested-by: Dan Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2026-08-06 09:48:29 -04:00
Paolo Bonzini
c6e127b88c 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.
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Merge tag 'kvm-s390-master-7.2-3' of https://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux into HEAD

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.
2026-08-06 15:47:46 +02:00
Paolo Bonzini
26505e1b5b KVM: SVM: make svm_flush_tlb_gva do a full asid flush if NPT enabled
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>
2026-08-06 15:46:46 +02:00
Kumar Kartikeya Dwivedi
8c7f55d60a Merge branch 'bpf-track-overlapping-rcu-protection'
Ning Ding says:

====================
bpf: Track overlapping RCU protection

Preemption-disabled and IRQ-disabled regions provide RCU protection, but
the verifier does not account for them. Current implementation can invalidate
a task kptr while another RCU source remains active, or keep it valid
after the final source ends.

Track these regions and invalidate RCU-protected pointers only after the
last protection ends. Add task kptr tests for overlapping protection and
final-exit rejection.

This follows review of the applied spin-unlock fix series [1].

Tested in QEMU/KVM:
  ./test_progs -t task_kfunc
  ./test_progs -t preempt_lock
  ./test_progs -t irq

[1] https://lore.kernel.org/r/20260803112615.3362122-1-dingning04@gmail.com
====================

Link: https://patch.msgid.link/20260805233940.3966981-1-dingning04@gmail.com
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
2026-08-06 15:46:43 +02:00