drm_for_each_bridge_in_chain_scoped() was added in commit e46efc6a7d
("drm/bridge: add drm_for_each_bridge_in_chain_scoped()") to provide a
safer alternative to drm_for_each_bridge_in_chain().
Following commits converted all users to the _scoped variant.
Finally commit 2f08387a44 ("drm/bridge: remove
drm_for_each_bridge_in_chain()") removed the old
drm_for_each_bridge_in_chain() macro.
It's time to rename drm_for_each_bridge_in_chain_scoped() back to the
original name.
Reviewed-by: Louis Chauvet <louis.chauvet@bootlin.com>
Link: https://patch.msgid.link/20260630-drm-bridge-alloc-getput-for_each_bridge-2-v2-1-e0a1094cd1eb@bootlin.com
Signed-off-by: Luca Ceresoli <luca.ceresoli@bootlin.com>
cxl_fw_prepare() classifies a firmware image as a one-shot transfer
only when its Transfer FW input payload is smaller than the mailbox
payload size. An image that exactly fills the payload is therefore
treated as a multi-part transfer.
The firmware loader invokes cxl_fw_write() only once for that image.
Since both offset == 0 and remaining == 0, the multi-part action
selection sends INITIATE, never sends END, and then attempts to activate
the target slot.
Include equality in the one-shot classification so exact-fit images use
the FULL action.
Fixes: 9521875bbe ("cxl: add a firmware update mechanism using the sysfs firmware loader")
Signed-off-by: Guzebing <Guzebing1612@gmail.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Link: https://patch.msgid.link/20260713112744.2543829-1-guzebing1612@gmail.com
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
The witable override should be set when FDO_MODE bit is enabled.
Fix the comparison to distingush this case from legacy systems
where bit should be disabled to have override.
Cc: stable@vger.kernel.org
Fixes: 9dde74fd9e ("drm/xe/nvm: enable cri platform")
Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Link: https://patch.msgid.link/20260714-cri_nvm_fdo_flip-v2-1-14580e71b58e@intel.com
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Add compatible string fsl,imx8qm-sc-key for i.MX8QM and fallback to
fsl,imx-sc-key.
Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Frank Li <Frank.Li@nxp.com>
When the interrupt status register reads zero, the handler should
return IRQ_NONE instead of IRQ_HANDLED. What the return value
actually feeds into is the spurious interrupt accounting in
note_interrupt(): falsely claiming IRQ_HANDLED defeats the "irq XX:
nobody cared" detection, so a stuck interrupt source would never be
caught.
Fixes: 5ea558473f ("i2c: spacemit: add support for SpacemiT K1 SoC")
Signed-off-by: Pei Xiao <xiaopei01@kylinos.cn>
Cc: <stable@vger.kernel.org> # v6.15+
Reviewed-by: Troy Mitchell <troy.mitchell@linux.spacemit.com>
Reviewed-by: Mukesh Savaliya <mukesh.savaliya@oss.qualcomm.com>
Signed-off-by: Andi Shyti <andi.shyti@kernel.org>
Link: https://lore.kernel.org/r/ef8b623f45d4e430721e46572c2598d882044aed.1783667875.git.xiaopei01@kylinos.cn
New transcoder enum values (for CMTG) were recently added which pushed
the maximum transcoder mask beyond 8bits. The patch in question
updated the info structure's u8 to u16 but not any of the functions
that process transcoder masks. So fix those as well.
v2: Fix more instances (found by Sashiko)
Signed-off-by: John Harrison <John.Harrison@Igalia.com>
Fixes: 789dda6429 ("drm/i915/cmtg: Add CMTG transcoder offset in struct _device_info")
Cc: Uma Shankar <uma.shankar@intel.com>
Cc: Animesh Manna <animesh.manna@intel.com>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: intel-gfx@lists.freedesktop.org
Cc: intel-xe@lists.freedesktop.org
Reviewed-by: Uma Shankar <uma.shankar@intel.com>
Link: https://patch.msgid.link/20260713234138.3861243-1-John.Harrison@Igalia.com
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
cxl_type2_mem_init() is used to set up mock CXL type2 memory device for
cxl testing, it introduces a known bug fixed by the following commit:
commit d90f236f8b ("cxl/test: Update mock dev array before calling platform_device_add()")
Mock CXL devices require updating the mock device array prior to
platform_device_add(), otherwise, the CXL subsystem could fail to
recognize the newly added mock device. Switch to
cxl_mock_platform_device_add() helper to resolve this ordering issue.
Besides, this patch also includes two minor changes.
1. Preserve the original error code returned by
cxl_mock_platform_device_add(), rather than unconditionally
overriding it with -ENOMEM.
2. Drop redundant NULL check before platform_device_unregister(), as the
function internally handles NULL pointer.
Fixes: 6b2e585142 ("cxl/test: Add hierarchy enumeration support for type2 device")
Signed-off-by: Li Ming <ming.li@zohomail.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Link: https://patch.msgid.link/20260713061531.56322-1-ming.li@zohomail.com
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Commit 280ea9c315 ("mm/slab: avoid allocating slabobj_ext array from
its own slab") avoided recursive allocation of obj_exts from kmalloc
caches of the same size, by bumping the obj_exts array's allocation
size whenever the array size equals the size of the object being
allocated.
However, as reported by Danielle Costantino and Shakeel Butt,
even slabs from kmalloc caches of different sizes can form a cycle
by allocating obj_exts arrays from each other [1]:
What happened: a KMALLOC_NORMAL slab's obj_exts array (used by
allocation profiling / memcg accounting) is itself kmalloc()'d from a
KMALLOC_NORMAL cache, so the "slab holds another slab's obj_exts array"
relation can form cycles. With sizeof(struct slabobj_ext) == 16 and
the host's geometry:
- kmalloc-512 has 64 objects/slab -> array is 64*16 == 1024 bytes,
served from kmalloc-1k;
- kmalloc-1k has 32 objects/slab -> array is 32*16 == 512 bytes,
served from kmalloc-512.
A kmalloc-512 slab and a kmalloc-1k slab therefore hold each other's
obj_exts array. Discarding one frees the other's array, which empties
and discards that slab, which frees the first's array, and so on:
__free_slab() -> free_slab_obj_exts() -> kfree() -> discard_slab() ->
__free_slab() recurses along the cycle until the stack is exhausted.
With memory allocation profiling, this allows unbounded recursion
in the free path and led to a stack overflow on a production host in
the Meta fleet [1]:
BUG: TASK stack guard page was hit
Oops: stack guard page
RIP: 0010:kfree+0x8/0x5d0
Call Trace:
__free_slab+0x66/0xc0
kfree+0x3f0/0x5d0
... ( ~125x __free_slab <-> kfree ) ...
<kernel driver freeing a resource>
do_syscall_64
It is proposed [1] to resolve this issue by always serving the obj_exts
array allocation from kmalloc caches (or large kmalloc) of sizes larger
than the object size. However, as pointed out by Vlastimil Babka [2],
this can waste an excessive amount of memory as slabs from large
kmalloc sizes (e.g. kmalloc-8k) generally need obj_exts arrays much
smaller than the object size.
Therefore, rather than bumping the size, let us take a different
approach; disallow formation of cycles between kmalloc types when
allocating obj_exts arrays. Currently, all obj_exts arrays are served
from normal kmalloc caches. Cycles cannot be created if obj_exts arrays
of normal kmalloc caches are served from a special kmalloc type that can
never have obj_exts arrays.
To achieve this, create a new kmalloc type called KMALLOC_NO_OBJ_EXT.
KMALLOC_NO_OBJ_EXT caches are created with SLAB_NO_OBJ_EXT flag when
either 1) memory allocation profiling is not permanently disabled,
or 2) kmalloc types with a priority higher than KMALLOC_CGROUP are
aliased with KMALLOC_NORMAL.
Sheaf bootstrapping for KMALLOC_NO_OBJ_EXT caches now must be deferred
because allocation of a barn can trigger obj_exts array allocation of
normal kmalloc caches when the KMALLOC_NO_OBJ_EXT cache for that size
is not ready yet. For simplicity, perform bootstrapping of sheaves for
all kmalloc caches later.
Introduce a new slab alloc flag, SLAB_ALLOC_NO_OBJ_EXT, to prevent
allocation of obj_exts arrays, and let kmalloc_slab() override the type
to KMALLOC_NO_OBJ_EXT when specified. Note that kmalloc_type() remains
unchanged because kmalloc_flags() bypasses the kmalloc fastpath.
Do not pass SLAB_ALLOC_NO_RECURSE to kmalloc_flags() in
alloc_slab_obj_exts() and instead use SLAB_ALLOC_NO_OBJ_EXT only when
the objects are allocated from normal kmalloc caches. While this
prevents unbounded recursive allocation of obj_exts, it allows
KMALLOC_NO_OBJ_EXT caches to have sheaves.
Since sheaf allocations specify SLAB_ALLOC_NO_RECURSE that prevents
allocation of both sheaves and obj_exts arrays, the recursion depth
is bounded.
obj_exts arrays for non-kmalloc-normal caches can now have a valid tag.
Do not call mark_obj_codetag_empty() when freeing an obj_exts array to
avoid false warnings. KMALLOC_NO_OBJ_EXT don't need this as they never
allocate those arrays.
Reported-by: Danielle Costantino <dcostantino@meta.com>
Reported-by: Shakeel Butt <shakeel.butt@linux.dev>
Closes: https://lore.kernel.org/linux-mm/20260625230029.703750-1-shakeel.butt@linux.dev [1]
Fixes: 4b87369646 ("mm/slab: add allocation accounting into slab allocation and free paths")
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/linux-mm/c5c4208d-a6f0-413e-bad9-49be12f12d55@kernel.org [2]
Signed-off-by: Harry Yoo (Oracle) <harry@kernel.org>
Reviewed-by: Suren Baghdasaryan <surenb@google.com>
Link: https://patch.msgid.link/20260713-kmalloc-no-objext-v3-4-47c7bd138de7@kernel.org
Signed-off-by: Vlastimil Babka (SUSE) <vbabka@kernel.org>
Resolves the merge conflicts in:
drivers/android/binder/node.rs
drivers/android/binder/process.rs
As done by linux-next
Reported-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Document the NOIOMMU mode with newly added cdev support under iommufd.
Link: https://patch.msgid.link/r/7d4a050505317a29f7f2c32d024333b7b5c7d4fd.1783360051.git.jacob.pan@linux.microsoft.com
Cc: Jonathan Corbet <corbet@lwn.net>
Reviewed-by: Yi Liu <yi.l.liu@intel.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Jacob Pan <jacob.pan@linux.microsoft.com>
Fixes: 2c6cf6ab1564 ("iommufd: Allow binding to a noiommu device")
Reviewed-by: Alex Williamson <alex@shazbot.org>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Now that devices under noiommu mode can bind with IOMMUFD and perform
IOAS operations, lift restrictions on cdev from VFIO side.
Use cases are documented in Documentation/driver-api/vfio.rst
Link: https://patch.msgid.link/r/fdac3395ecc52f87b722b54a055ced66733dc48f.1783360051.git.jacob.pan@linux.microsoft.com
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Pranjal Shrivastava <praan@google.com>
Reviewed-by: Yi Liu <yi.l.liu@intel.com>
Reviewed-by: Alex Williamson <alex@shazbot.org>
Signed-off-by: Jacob Pan <jacob.pan@linux.microsoft.com>
Fixes: 2c6cf6ab1564 ("iommufd: Allow binding to a noiommu device")
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
To support no-IOMMU mode where userspace drivers perform unsafe DMA
using physical addresses, introduce a new API to retrieve the
physical address of a user-allocated DMA buffer that has been mapped to
an IOVA via IOMMU_IOAS_MAP. The mapping is backed by SW-only I/O page
tables maintained by the GENERIC_PT framework.
Link: https://patch.msgid.link/r/a60a601509688e8552c75e668deb548c93974a3b.1783360051.git.jacob.pan@linux.microsoft.com
Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Pranjal Shrivastava <praan@google.com>
Reviewed-by: Yi Liu <yi.l.liu@intel.com>
Suggested-by: Jason Gunthorpe <jgg@nvidia.com>
Co-developed-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Jacob Pan <jacob.pan@linux.microsoft.com>
Fixes: 2c6cf6ab1564 ("iommufd: Allow binding to a noiommu device")
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Allow iommufd to bind devices without an IOMMU (noiommu mode) by creating
a dummy igroup for such devices and skipping hwpt operations.
This enables noiommu devices to operate through the same iommufd API as IOMMU-
capable devices.
Link: https://patch.msgid.link/r/2c6cf6ab1564426050e637863c9b0d3b25541c63.1783360051.git.jacob.pan@linux.microsoft.com
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Yi Liu <yi.l.liu@intel.com>
Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: Pranjal Shrivastava <praan@google.com>
Signed-off-by: Jacob Pan <jacob.pan@linux.microsoft.com>
Fixes: 2c6cf6ab1564 ("iommufd: Allow binding to a noiommu device")
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
mem_alloc_profiling_enabled() tells whether memalloc profiling is
currently enabled. However, even when this function returns false,
it can be enabled later.
However, this is not enough. Some optimizations can be applied only when
memalloc profiling is permanently disabled. For example, to skip the
creation of KMALLOC_NO_OBJ_EXT caches at boot time, mem_profiling must
be set to "never", "0" w/ debugging on, or have been shutdown so that
it can no longer be enabled.
Introduce mem_alloc_profiling_permanently_disabled() for this purpose.
Signed-off-by: Harry Yoo (Oracle) <harry@kernel.org>
Acked-by: Suren Baghdasaryan <surenb@google.com>
Link: https://patch.msgid.link/20260713-kmalloc-no-objext-v3-3-47c7bd138de7@kernel.org
Signed-off-by: Vlastimil Babka (SUSE) <vbabka@kernel.org>
Bootstrap caches are created with SLAB_NO_OBJ_EXT to disallow sheaves
and obj_exts.
To allow disabling obj_exts while allowing sheaves, decouple
SLAB_NO_SHEAVES from SLAB_NO_OBJ_EXT. Bootstrap caches now have both
SLAB_NO_SHEAVES and SLAB_NO_OBJ_EXT.
No functional change intended.
Reviewed-by: Vlastimil Babka (SUSE) <vbabka@kernel.org>
Signed-off-by: Harry Yoo (Oracle) <harry@kernel.org>
Reviewed-by: Suren Baghdasaryan <surenb@google.com>
Link: https://patch.msgid.link/20260713-kmalloc-no-objext-v3-2-47c7bd138de7@kernel.org
Signed-off-by: Vlastimil Babka (SUSE) <vbabka@kernel.org>
Enable CONFIG_GPIOLIB in all_tests.config to ensure the kunit test cases
for GPIO core can be built with this config.
Link: https://lore.kernel.org/r/20260629124245.27674-1-bartosz.golaszewski@oss.qualcomm.com
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>
Reviewed-by: David Gow <david@davidgow.net>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
SMBus 3.1 6.5.7 allows a Block Read byte count of 0, but the
interrupt-driven block-read state machine rejects it as -EPROTO. Worse,
it returns without a NACK+STOP: the next receive cycle has already
started, so the target keeps holding SDA and the bus stays stuck until a
power cycle of this i2c controller.
Accept count=0: NACK the in-flight dummy byte (TXAK) and set msg->len to
2 so i2c_imx_isr_read_continue() emits STOP via its normal last-byte
path. The dummy byte is discarded; block-read callers only consume
buf[0..count-1].
Reading I2DR has likewise already armed the next byte on the
count > I2C_SMBUS_BLOCK_MAX error path, so NACK it (TXAK) before aborting
with -EPROTO; otherwise the failing transfer's STOP cannot complete and
the bus stays held.
The atomic path regressed earlier (v3.16) and is fixed separately; this
patch covers only the v6.13 state-machine rework.
Fixes: 5f5c2d4579 ("i2c: imx: prevent rescheduling in non dma mode")
Signed-off-by: Vincent Jardin <vjardin@free.fr>
Cc: <stable@vger.kernel.org> # v6.13+
Acked-by: Oleksij Rempel <o.rempel@pengutronix.de>
Acked-by: Carlos Song <carlos.song@nxp.com>
Reviewed-by: Stefan Eichenberger <eichest@gmail.com>
Signed-off-by: Andi Shyti <andi.shyti@kernel.org>
Link: https://lore.kernel.org/r/20260713-for-upstream-i2c-lx2160-fix-v1-v3-2-073ac9e103a5@free.fr
When kmalloc caches are aliased, multiple cache pointers reference
the same kmem_cache. As a result, iterating over kmalloc indices and
bootstrapping sheaves can bootstrap the same cache more than once and
leak memory.
Currently, this could happen when the architecture specifies
minimum alignment for slab caches that is larger than
ARCH_KMALLOC_MINALIGN.
Bootstrap sheaves only when the cache does not have them already.
Add a warning when bootstrap_cache_sheaves() is called for a cache
that already has sheaves enabled.
Fixes: 913ffd3a1b ("slab: handle kmalloc sheaves bootstrap")
Cc: stable@vger.kernel.org
Signed-off-by: Harry Yoo (Oracle) <harry@kernel.org>
Reviewed-by: Suren Baghdasaryan <surenb@google.com>
Link: https://patch.msgid.link/20260713-kmalloc-no-objext-v3-1-47c7bd138de7@kernel.org
Signed-off-by: Vlastimil Babka (SUSE) <vbabka@kernel.org>
SMBus 3.1 6.5.7 allows a Block Read byte count of 0, but the atomic
(polling) path rejects it as -EPROTO. Worse, it returns without a
NACK+STOP: the next receive cycle has already started, so the target
keeps holding SDA and the bus stays stuck until a power cycle for
this i2c controller.
Reading I2DR to obtain the count likewise arms the next byte on the
count > I2C_SMBUS_BLOCK_MAX path, which also returned -EPROTO directly
and left the bus held.
Handle both: NACK the in-flight dummy byte (TXAK) and extend msgs->len so
the existing last-byte handling emits STOP; the dummy byte is discarded.
A count of 0 is a valid empty block read; a count above
I2C_SMBUS_BLOCK_MAX is still reported as -EPROTO, but only after the bus
has been released.
The interrupt-driven path has the same flaw from a later commit and is
fixed separately, as it carries a different Fixes: tag and stable range.
Fixes: 8e8782c715 ("i2c: imx: add SMBus block read support")
Signed-off-by: Vincent Jardin <vjardin@free.fr>
Cc: <stable@vger.kernel.org> # v3.16+
Acked-by: Oleksij Rempel <o.rempel@pengutronix.de>
Acked-by: Carlos Song <carlos.song@nxp.com>
Reviewed-by: Stefan Eichenberger <eichest@gmail.com>
Signed-off-by: Andi Shyti <andi.shyti@kernel.org>
Link: https://lore.kernel.org/r/20260713-for-upstream-i2c-lx2160-fix-v1-v3-1-073ac9e103a5@free.fr
Currently, only x86 genuinely implements and supports Syscall User Dispatch
(SUD).
Multiple architectures provide a stub arch_syscall_is_vdso_sigreturn()
returning 'false' simply to satisfy GENERIC_ENTRY compilation, which
creates a false impression of feature support.
Introduce ARCH_SUPPORTS_SYSCALL_USER_DISPATCH to decouple this mechanism
from GENERIC_ENTRY. Select it exclusively on x86 and remove the redundant
stub functions from other architectures.
Suggested-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Jinjie Ruan <ruanjinjie@huawei.com>
Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Reviewed-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Link: https://patch.msgid.link/20260713035422.582771-1-ruanjinjie@huawei.com
Sashiko review pointed out the following issue.
If a thread is stopped in syscall_trace_enter() for ptrace, another
thread can install a seccomp filter with SECCOMP_FILTER_FLAG_TSYNC
(e.g., via seccomp_attach_filter()). This will successfully set
SYSCALL_WORK_SECCOMP on the stopped thread, but syscall_trace_enter()
evaluates a cached 'work' variable sampled on entry. Consequently,
the subsequent check for SYSCALL_WORK_SECCOMP misses the newly
assigned flag, and the filter is silently bypassed.
This race condition could allow an unprivileged process to execute
a prohibited system call (e.g., execve) that the newly installed filter
was intended to block, especially since the tracer might have modified
the system call number during the ptrace stop.
Fix this by re-reading the syscall_work flags after ptrace handling,
so that any new SYSCALL_WORK_SECCOMP flag set by another thread via
TSYNC during the ptrace stop is observed before the subsequent
seccomp check.
Fixes: 142781e108 ("entry: Provide generic syscall entry functionality")
Signed-off-by: Jinjie Ruan <ruanjinjie@huawei.com>
Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/all/20260629132914.1135C1F000E9@smtp.kernel.org/
Link: https://patch.msgid.link/20260713025712.416366-1-ruanjinjie@huawei.com
Wolfram Sang has decided that a decade-plus of I2C was enough and
is moving on to new things.
Thank you, Wolfram, for your years of dedication and for keeping
the bus in line. Your legacy is now officially cemented in the
CREDITS file.
Suggested-by: Sebastian Reichel <sre@kernel.org>
Signed-off-by: Andi Shyti <andi.shyti@kernel.org>
Cc: Wolfram Sang <wsa@kernel.org>
Reviewed-by: Wolfram Sang <wsa@kernel.org>
Link: https://lore.kernel.org/r/20260625163221.183414-1-andi.shyti@kernel.org
The H616 codec does not have capture capabilities. Set the
.playback_only quirks flag to denote this.
This was somehow missing from the original driver patch, even though
the patch prior to it in the series added this quirk.
Fixes: 9155c321a1 ("ASoC: sun4i-codec: support allwinner H616 codec")
Signed-off-by: Chen-Yu Tsai <wens@kernel.org>
Link: https://patch.msgid.link/20260714113304.270224-1-wens@kernel.org
Signed-off-by: Mark Brown <broonie@kernel.org>
So it can be reused in the next patch which allows binding to noiommu
device.
Link: https://patch.msgid.link/r/6bc8e5eaee89e1dc5f07d13dff69b9670b55923a.1783360051.git.jacob.pan@linux.microsoft.com
Reviewed-by: Samiullah Khawaja <skhawaja@google.com>
Reviewed-by: Yi Liu <yi.l.liu@intel.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Jacob Pan <jacob.pan@linux.microsoft.com>
Fixes: 2c6cf6ab1564 ("iommufd: Allow binding to a noiommu device")
Reviewed-by: Pranjal Shrivastava <praan@google.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Create just a little part of a real iommu driver, enough to
slot in under the dev_iommu_ops() and allow iommufd to call
domain_alloc_paging_flags() and fail everything else.
This allows explicitly creating a HWPT under an IOAS.
A new Kconfig option IOMMUFD_NOIOMMU is introduced to differentiate
from the VFIO group/container based noiommu mode.
Link: https://patch.msgid.link/r/8d1ad0b90db0381d4139eda5c126cc8d168d89f8.1783360051.git.jacob.pan@linux.microsoft.com
Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: Samiullah Khawaja <skhawaja@google.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Pranjal Shrivastava <praan@google.com>
Signed-off-by: Jacob Pan <jacob.pan@linux.microsoft.com>
Fixes: 2c6cf6ab1564 ("iommufd: Allow binding to a noiommu device")
Reviewed-by: Yi Liu <yi.l.liu@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
arm_vsmmu_vsid_to_sid() maps a guest's vSID to a single physical Stream ID
taken from master->streams[0], assuming a device has exactly one stream. A
device with several streams gets only its first one mapped, so a guest vSID
invalidation cannot reach the others' ATC and IOTLB entries; a device with
none makes master->streams a ZERO_SIZE_PTR, read out of bounds.
Add an arm_vsmmu_vdevice_init() op to reject the vDEVICE with -EOPNOTSUPP
when master->num_streams is not one, rather than mapping it silently.
Fixes: d68beb276b ("iommu/arm-smmu-v3: Support IOMMU_HWPT_INVALIDATE using a VIOMMU object")
Link: https://patch.msgid.link/r/b15f2b73520f389f3f57881da2f040e7bdc18876.1783311134.git.nicolinc@nvidia.com
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Assisted-by: Claude:claude-opus-4-8
Reviewed-by: Pranjal Shrivastava <praan@google.com>
Signed-off-by: Nicolin Chen <nicolinc@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
iommufd_vdevice_alloc_ioctl() adds the vDEVICE to the viommu->vdevs xarray
with xa_cmpxchg() before the driver's vdevice_init() op runs. That op is
where a driver validates the device and may reject it, but the xarray entry
is already live by then: a concurrent IOMMU_HWPT_INVALIDATE can look it up
with iommufd_viommu_find_dev() and run the driver invalidation path against
a device that vdevice_init() would have refused.
Reserve the index with xa_insert(): it stores a zero entry that reads back
as NULL, and returns -EBUSY on a duplicate virt_id. Run vdevice_init() and
store the vDEVICE pointer only once it succeeds. A failed vdevice_init()
releases the reservation, so lookups observe the vDEVICE only after it is
fully initialized and accepted.
Fixes: ed42eee797 ("iommufd/viommu: Add driver-defined vDEVICE support")
Link: https://patch.msgid.link/r/1e05999347f4bf583edbc6a1312c857d5548708c.1783311134.git.nicolinc@nvidia.com
Cc: stable@vger.kernel.org
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Assisted-by: Claude:claude-opus-4-8
Reviewed-by: Pranjal Shrivastava <praan@google.com>
Signed-off-by: Nicolin Chen <nicolinc@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
iommufd_vdevice_alloc_ioctl() takes idev->igroup->lock, then validates the
driver's vdevice_size against the core structure size with a WARN_ON_ONCE.
On failure that guard jumps to out_put_idev, below out_unlock_igroup, so it
skips the mutex_unlock(), leaving the igroup lock held and deadlocking the
next vDEVICE operation on that group.
Jump to out_unlock_igroup instead.
Fixes: ed42eee797 ("iommufd/viommu: Add driver-defined vDEVICE support")
Link: https://patch.msgid.link/r/e903f775d491296a525097e2a90b3eb6a47cf2ef.1783311134.git.nicolinc@nvidia.com
Cc: stable@vger.kernel.org
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Assisted-by: Claude:claude-opus-4-8
Reviewed-by: Pranjal Shrivastava <praan@google.com>
Signed-off-by: Nicolin Chen <nicolinc@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Peiyang reports that this function indirectly includes a fault injection
point through iommufd_get_object() that was intended to cover the uAPI use
of object IDs, not in places like this that cannot fail.
On deeper inspection this can be written using a dedicated helper to
obtain a users refcount relying entirely on the xa locking instead of
going through the whole get/put scheme. The new helper doesn't need the
fault injection point.
Fixes: 850f14f5b9 ("iommufd: Destroy vdevice on idevice destroy")
Link: https://patch.msgid.link/r/0-v1-719003d53a5b+38b-iommufd_fault_inj_vdev_jgg@nvidia.com
Reported-by: Peiyang He <peiyang_he@smail.nju.edu.cn>
Closes: https://lore.kernel.org/r/870BB9ADBBEDDD1A+37c5bfab-ad32-4fc5-a302-57c81a8432b5@smail.nju.edu.cn
Reviewed-by: Nicolin Chen <nicolinc@nvidia.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
To avoid potential stack overflows on limited kernel stacks, convert
parse_probe_arg() from a recursive function into a loop-based
implementation with a simple local state stack.
Since recursion is eliminated using a loop with a fixed-size
stack in the context, this restricts the dereference nesting
depth. The maximum nesting depth of dereferences is now restricted
to the same limit as typecasts (TRACEPROBE_MAX_NESTED_LEVEL, which
is 8) and reports the same TOO_MANY_NESTED error. Update ftrace
selftests to reflect this restriction and simplify the checks.
Note that this change slightly alters the behavior of nested
dereferencing in fetcharg. Previously, dereferencing without BTF
allowed for up to 14 levels of nesting, whereas dereferencing
with BTF was limited to 3 levels. With this change, the nesting
depth is now limited to 8 levels in both cases.
Link: https://lore.kernel.org/all/178399141396.27810.5390060618628718661.stgit@devnote2/
Assisted-by: Antigravity:gemini-3.5-flash
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
To support BTF argument parsing (such as accessing fields within nested
structures via typecasting), the maximum argument string length needs
to be extended. Extend MAX_ARGSTR_LEN from 63 to 255.
Since MAX_ARGSTR_LEN was previously reused to format command heads in
trace_*probe_match_command_head() functions, introduce a dedicated
MAX_COMMON_HEAD_LEN (63) macro for matching command heads and switch
these functions to use the new macro.
Link: https://lore.kernel.org/all/178399140457.27810.11387684872148824707.stgit@devnote2/
Assisted-by: Antigravity:gemini-3.5-flash
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Decompose parse_probe_vars() by extracting retval, stack, current task
struct, and function argument parsing logic into dedicated static
helper functions (parse_probe_var_retval, parse_probe_var_stack,
parse_probe_var_current, and parse_probe_var_arg). This simplifies
parse_probe_vars() and improves its readability.
Link: https://lore.kernel.org/all/178399137612.27810.14869178899276413372.stgit@devnote2/
Assisted-by: Antigravity:gemini-3.5-flash
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
fp pointer and unsigned long have the same size on all relevant
architectures that build Linux. Furthermore this struct is only used in
architectures that do not set ARCH_DEFINE_ENCODE_FPROBE_HEADER which is
set only for 64bit architectures (apart from LoongArch).
Both fields are aligned on these architectures so the struct with
__packed and without it are the same.
Remove the __packed as it is unnecessary.
[Masami: Removed Fixes tag because this is not fixing any problem.]
Link: https://lore.kernel.org/all/20260428-topic-fprobe-packed-v7-1-v1-1-9abc9b866b4c@baylibre.com/
Signed-off-by: Markus Schneider-Pargmann (The Capable Hub) <msp@baylibre.com>
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
With the introduction of container_of-style BTF typecasting and
per-CPU variable access support in trace probes, we need a way to
verify their functionality and prevent regressions.
Add a new ftrace kselftest and update the trace event sample module
to test and validate these features.
Specifically, update the trace-events-sample module to set up a
periodic timer whose callback accesses a per-CPU counter. Introduce
a new sample trace event, foo_timer_fn, to trace this callback
and log the current counter value.
Then, add a new test case, btf_probe_event.tc, which defines a
dynamic probe on the timer callback. The probe uses BTF typecasting
to recover the parent structure from the timer argument and
this_cpu_read() to fetch the per-CPU counter. The test verifies
the integrity of the implementation by ensuring the values
recorded by the dynamic probe match those from the static tracepoint.
Link: https://lore.kernel.org/all/178271368625.1176915.13502654445483530822.stgit@devnote2/
Assisted-by: Antigravity:gemini-3.5-flash
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
When tracing the kernel local variables, sometimes we need to get the
CPU local variables. To access it, current simple dereference is not
enough.
Thus, introduce a special this_cpu_read() dereference to access per-cpu
variable for the current CPU (accessing other CPU variable may race with
updates on other CPUs). Also this_cpu_ptr() is for accessing per-cpu
pointer.
Those are working as same as the kernel percpu macro.
Link: https://lore.kernel.org/all/178271367680.1176915.4711734074448973989.stgit@devnote2/
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Since we can use the BTF to cast value to a structure pointer type,
it is useful to introduce "$current" special variable support to
fetcharg.
User can define a fetcharg to access current task_struct properties
using BTF info. e.g.
$current->cpus_ptr
Link: https://lore.kernel.org/all/178271366709.1176915.15320906169981578568.stgit@devnote2/
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Add a field specifier option for the typecast. This works like
container_of() macro.
(STRUCT[,FIELD[.FIELD2...]])VAR
This is equivalent to :
container_of(VAR, struct STRUCT, FIELD[.FIELD2...])
For example:
echo "f tick_nohz_handler next_tick=(tick_sched,sched_timer)timer->next_tick" >> dynamic_events
This will trace tick_nohz_handler() with its tick_sched::next_tick which
is converted from @timer by contianer_of(tick, struct tick_sched, sched_timer).
So, if you enabkle both fprobes:tick_nohz_handler__entry and
timer:hrtimer_expire_entry events, we will see something like:
<idle>-0 [002] d.h1. 3778.087272: hrtimer_expire_entry: hrtimer=00000000d63db328 f
unction=tick_nohz_handler now=3777450051040
<idle>-0 [002] d.h1. 3778.087281: tick_nohz_handler__entry: (tick_nohz_handler+0x4
/0x140) next_tick=3777450000000
Link: https://lore.kernel.org/all/178271365745.1176915.725923927180862257.stgit@devnote2/
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
This allows type casting to various fetchargs without parentheses
by recursively calling parse_probe_arg on the target when type
casting is used.
For example, this allows the following expressions:
- (STRUCT)%REG->FIELD
- (STRUCT)$stackN->FIELD
- (STRUCT)@SYM->FIELD
Note that @SYM+/-OFFSET with typecast needs parentheses like:
- (STRUCT)(@SYM-8)->FIELD
Link: https://lore.kernel.org/all/178271364804.1176915.17600229399446264813.stgit@devnote2/
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
When we hit an open parenthesis right after typecast closing
parenthesis, it means we have nested typecast. This allows us to
typecast a generic data member in a structure to a pointer to
another structure.
For example, to cast a DATA_MEMBER of VAR structure to STRUCT pointer
and get MEMBER value.
(STRUCT)(VAR->DATA_MEMBER)->MEMBER
Also, we can nest typecast.
(STRUCT1)((STRUCT2)$ARG->FIELD2)->FIELD1
Currently the max nest level is limited to 3.
This also allows user to use typecasting for registers or stacks on
kprobe events. e.g.
(STRUCT)(%ax)->MEMBER
(STRUCT)($stack0)->MEMBER
Link: https://lore.kernel.org/all/178271363855.1176915.16793301788257446529.stgit@devnote2/
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Support BTF typecast feature on other probe events, but only if it is
kernel function entry or return, and must use function parameter name
or $retval. This means you can do:
(STRUCT)PARAM->MEMBER
Note: you can not use other variables like $stackN, %reg etc. That
needs nesting support.
To support other probe events, we just need to use last_struct type
when we find a function parameter in parse_btf_arg().
This also updates <tracefs>/README file to show struct typecast.
Link: https://lore.kernel.org/all/178271362928.1176915.12235759508786922490.stgit@devnote2/
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Admin-only PF mode does not expose media or 3D execution capabilities
to userspace, so display pipelines cannot receive rendered content.
Fixes: d88c4bac8c ("drm/xe/pf: Restrict device query responses in admin-only PF mode")
Signed-off-by: Satyanarayana K V P <satyanarayana.k.v.p@intel.com>
Cc: Michal Wajdeczko <michal.wajdeczko@intel.com>
Cc: Piotr Piórkowski <piotr.piorkowski@intel.com>
Cc: Michał Winiarski <michal.winiarski@intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Reviewed-by: Piotr Piórkowski <piotr.piorkowski@intel.com>
Link: https://patch.msgid.link/20260714053259.504308-2-satyanarayana.k.v.p@intel.com
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Prefer to use system memory for global framebuffers, and reserve
the space for FBC use only.
Now that multiple CRTC's can use FBC's, the simple heuristic
of using less than half of stolen is no longer sufficient.
Additionally, there are reports of system hangs when using stolen
memory, and there are also various workarounds that are avoided
by using system memory instead.
Link: https://gitlab.freedesktop.org/drm/xe/kernel/-/work_items/7513
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patch.msgid.link/20260630135523.1775379-4-dev@lankhorst.se
Signed-off-by: Maarten Lankhorst <dev@lankhorst.se>
Acked-by: Matthew Brost <matthew.brost@intel.com> #teams
