tjh.dev
Linux kernel
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Memory allocated for idxd is not freed if an error occurs during
idxd_pci_probe(). To fix it, free the allocated memory in the reverse
order of allocation before exiting the function in case of an error.
Fixes: bfe1d56091c1 ("dmaengine: idxd: Init and probe for Intel data accelerators")
Cc: stable@vger.kernel.org
Signed-off-by: Shuai Xue <xueshuai@linux.alibaba.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Reviewed-by: Fenghua Yu <fenghuay@nvidia.com>
Link: https://lore.kernel.org/r/20250404120217.48772-8-xueshuai@linux.alibaba.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Memory allocated for idxd is not freed if an error occurs during
idxd_alloc(). To fix it, free the allocated memory in the reverse order
of allocation before exiting the function in case of an error.
Fixes: a8563a33a5e2 ("dmanegine: idxd: reformat opcap output to match bitmap_parse() input")
Cc: stable@vger.kernel.org
Signed-off-by: Shuai Xue <xueshuai@linux.alibaba.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Reviewed-by: Fenghua Yu <fenghuay@nvidia.com>
Link: https://lore.kernel.org/r/20250404120217.48772-7-xueshuai@linux.alibaba.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
The idxd_cleanup_internals() function only decreases the reference count
of groups, engines, and wqs but is missing the step to release memory
resources.
To fix this, use the cleanup helper to properly release the memory
resources.
Fixes: ddf742d4f3f1 ("dmaengine: idxd: Add missing cleanup for early error out in probe call")
Cc: stable@vger.kernel.org
Signed-off-by: Shuai Xue <xueshuai@linux.alibaba.com>
Reviewed-by: Fenghua Yu <fenghuay@nvidia.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/20250404120217.48772-6-xueshuai@linux.alibaba.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
The idxd_setup_internals() is missing some cleanup when things fail in
the middle.
Add the appropriate cleanup routines:
- cleanup groups
- cleanup enginces
- cleanup wqs
to make sure it exits gracefully.
Fixes: defe49f96012 ("dmaengine: idxd: fix group conf_dev lifetime")
Cc: stable@vger.kernel.org
Suggested-by: Fenghua Yu <fenghuay@nvidia.com>
Signed-off-by: Shuai Xue <xueshuai@linux.alibaba.com>
Reviewed-by: Fenghua Yu <fenghuay@nvidia.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/20250404120217.48772-5-xueshuai@linux.alibaba.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Memory allocated for groups is not freed if an error occurs during
idxd_setup_groups(). To fix it, free the allocated memory in the reverse
order of allocation before exiting the function in case of an error.
Fixes: defe49f96012 ("dmaengine: idxd: fix group conf_dev lifetime")
Cc: stable@vger.kernel.org
Signed-off-by: Shuai Xue <xueshuai@linux.alibaba.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Reviewed-by: Fenghua Yu <fenghuay@nvidia.com>
Link: https://lore.kernel.org/r/20250404120217.48772-4-xueshuai@linux.alibaba.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Memory allocated for engines is not freed if an error occurs during
idxd_setup_engines(). To fix it, free the allocated memory in the
reverse order of allocation before exiting the function in case of an
error.
Fixes: 75b911309060 ("dmaengine: idxd: fix engine conf_dev lifetime")
Cc: stable@vger.kernel.org
Signed-off-by: Shuai Xue <xueshuai@linux.alibaba.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Reviewed-by: Fenghua Yu <fenghuay@nvidia.com>
Link: https://lore.kernel.org/r/20250404120217.48772-3-xueshuai@linux.alibaba.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Memory allocated for wqs is not freed if an error occurs during
idxd_setup_wqs(). To fix it, free the allocated memory in the reverse
order of allocation before exiting the function in case of an error.
Fixes: 7c5dd23e57c1 ("dmaengine: idxd: fix wq conf_dev 'struct device' lifetime")
Fixes: 700af3a0a26c ("dmaengine: idxd: add 'struct idxd_dev' as wrapper for conf_dev")
Fixes: de5819b99489 ("dmaengine: idxd: track enabled workqueues in bitmap")
Fixes: b0325aefd398 ("dmaengine: idxd: add WQ operation cap restriction support")
Cc: stable@vger.kernel.org
Signed-off-by: Shuai Xue <xueshuai@linux.alibaba.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Reviewed-by: Fenghua Yu <fenghuay@nvidia.com>
Link: https://lore.kernel.org/r/20250404120217.48772-2-xueshuai@linux.alibaba.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
The variable is dereferenced without first checking if it's null, leading
to the following warning: 'Variable dereferenced before check: desc.'
drivers/dma/amd/ptdma/ptdma-dmaengine.c: pt_cmd_callback_work()
warn: variable dereferenced before check 'desc'
Therefore, move the condition check for the 'desc' variable to the first
place and remove the redundant extra condition check.
Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
Closes: https://lore.kernel.org/all/bfa0a979-ce9f-422d-92c3-34921155d048@stanley.mountain/
Fixes: 656543989457 ("dmaengine: ptdma: Utilize the AE4DMA engine's multi-queue functionality")
Signed-off-by: Basavaraj Natikar <Basavaraj.Natikar@amd.com>
Link: https://lore.kernel.org/r/20250421114215.1687073-1-Basavaraj.Natikar@amd.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Check if the process submitting the descriptor belongs to the same
address space as the one that opened the file, reject otherwise.
Fixes: 6827738dc684 ("dmaengine: idxd: add a write() method for applications to submit work")
Signed-off-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/20250421170337.3008875-1-dave.jiang@intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Recent kernels complain about a missing lock in k3-udma.c when the lock
validator is enabled:
[ 4.128073] WARNING: CPU: 0 PID: 746 at drivers/dma/ti/../virt-dma.h:169 udma_start.isra.0+0x34/0x238
[ 4.137352] CPU: 0 UID: 0 PID: 746 Comm: kworker/0:3 Not tainted 6.12.9-arm64 #28
[ 4.144867] Hardware name: pp-v12 (DT)
[ 4.148648] Workqueue: events udma_check_tx_completion
[ 4.153841] pstate: 60000005 (nZCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[ 4.160834] pc : udma_start.isra.0+0x34/0x238
[ 4.165227] lr : udma_start.isra.0+0x30/0x238
[ 4.169618] sp : ffffffc083cabcf0
[ 4.172963] x29: ffffffc083cabcf0 x28: 0000000000000000 x27: ffffff800001b005
[ 4.180167] x26: ffffffc0812f0000 x25: 0000000000000000 x24: 0000000000000000
[ 4.187370] x23: 0000000000000001 x22: 00000000e21eabe9 x21: ffffff8000fa0670
[ 4.194571] x20: ffffff8001b6bf00 x19: ffffff8000fa0430 x18: ffffffc083b95030
[ 4.201773] x17: 0000000000000000 x16: 00000000f0000000 x15: 0000000000000048
[ 4.208976] x14: 0000000000000048 x13: 0000000000000000 x12: 0000000000000001
[ 4.216179] x11: ffffffc08151a240 x10: 0000000000003ea1 x9 : ffffffc08046ab68
[ 4.223381] x8 : ffffffc083cabac0 x7 : ffffffc081df3718 x6 : 0000000000029fc8
[ 4.230583] x5 : ffffffc0817ee6d8 x4 : 0000000000000bc0 x3 : 0000000000000000
[ 4.237784] x2 : 0000000000000000 x1 : 00000000001fffff x0 : 0000000000000000
[ 4.244986] Call trace:
[ 4.247463] udma_start.isra.0+0x34/0x238
[ 4.251509] udma_check_tx_completion+0xd0/0xdc
[ 4.256076] process_one_work+0x244/0x3fc
[ 4.260129] process_scheduled_works+0x6c/0x74
[ 4.264610] worker_thread+0x150/0x1dc
[ 4.268398] kthread+0xd8/0xe8
[ 4.271492] ret_from_fork+0x10/0x20
[ 4.275107] irq event stamp: 220
[ 4.278363] hardirqs last enabled at (219): [<ffffffc080a27c7c>] _raw_spin_unlock_irq+0x38/0x50
[ 4.287183] hardirqs last disabled at (220): [<ffffffc080a1c154>] el1_dbg+0x24/0x50
[ 4.294879] softirqs last enabled at (182): [<ffffffc080037e68>] handle_softirqs+0x1c0/0x3cc
[ 4.303437] softirqs last disabled at (177): [<ffffffc080010170>] __do_softirq+0x1c/0x28
[ 4.311559] ---[ end trace 0000000000000000 ]---
This commit adds the missing locking.
Fixes: 25dcb5dd7b7c ("dmaengine: ti: New driver for K3 UDMA")
Cc: Peter Ujfalusi <peter.ujfalusi@gmail.com>
Cc: Vignesh Raghavendra <vigneshr@ti.com>
Cc: Vinod Koul <vkoul@kernel.org>
Cc: dmaengine@vger.kernel.org
Cc: stable@vger.kernel.org
Signed-off-by: Ronald Wahl <ronald.wahl@legrand.com>
Acked-by: Peter Ujfalusi <peter.ujfalusi@gmail.com>
Link: https://lore.kernel.org/r/20250414173113.80677-1-rwahl@gmx.de
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Currently, a local dma_cap_mask_t variable is used to store device
cap_mask within udma_of_xlate(). However, the DMA_PRIVATE flag in
the device cap_mask can get cleared when the last channel is released.
This can happen right after storing the cap_mask locally in
udma_of_xlate(), and subsequent dma_request_channel() can fail due to
mismatch in the cap_mask. Fix this by removing the local dma_cap_mask_t
variable and directly using the one from the dma_device structure.
Fixes: 25dcb5dd7b7c ("dmaengine: ti: New driver for K3 UDMA")
Cc: stable@vger.kernel.org
Signed-off-by: Vaishnav Achath <vaishnav.a@ti.com>
Acked-by: Peter Ujfalusi <peter.ujfalusi@gmail.com>
Reviewed-by: Udit Kumar <u-kumar1@ti.com>
Signed-off-by: Yemike Abhilash Chandra <y-abhilashchandra@ti.com>
Link: https://lore.kernel.org/r/20250417075521.623651-1-y-abhilashchandra@ti.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Several issues with this change:
* The analysis is flawed and it's unclear what problem is being
fixed. There is no difference between wait_event_freezable_timeout()
and wait_event_timeout() with respect to device interrupts. And of
course "the interrupt notifying the finish of an operation happens
during wait_event_freezable_timeout()" -- that's how it's supposed
to work.
* The link at the "Closes:" tag appears to be an unrelated
use-after-free in idxd.
* It introduces a regression: dmatest threads are meant to be
freezable and this change breaks that.
See discussion here:
https://lore.kernel.org/dmaengine/878qpa13fe.fsf@AUSNATLYNCH.amd.com/
Fixes: e87ca16e9911 ("dmaengine: dmatest: Fix dmatest waiting less when interrupted")
Signed-off-by: Nathan Lynch <nathan.lynch@amd.com>
Link: https://lore.kernel.org/r/20250403-dmaengine-dmatest-revert-waiting-less-v1-1-8227c5a3d7c8@amd.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Fix Smatch-detected issue:
drivers/dma/idxd/cdev.c:321 idxd_cdev_open() error:
uninitialized symbol 'sva'.
'sva' pointer may be used uninitialized in error handling paths.
Specifically, if PASID support is enabled and iommu_sva_bind_device()
returns an error, the code jumps to the cleanup label and attempts to
call iommu_sva_unbind_device(sva) without ensuring that sva was
successfully assigned. This triggers a Smatch warning about an
uninitialized symbol.
Initialize sva to NULL at declaration and add a check using
IS_ERR_OR_NULL() before unbinding the device. This ensures the
function does not use an invalid or uninitialized pointer during
cleanup.
Signed-off-by: Purva Yeshi <purvayeshi550@gmail.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Acked-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>
Link: https://lore.kernel.org/r/20250410110216.21592-1-purvayeshi550@gmail.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
The "real" linux/types.h UAPI header gracefully degrades to a NOOP when
included from assembly code.
Mirror this behaviour in the tools/ variant.
Test for __ASSEMBLER__ over __ASSEMBLY__ as the former is provided by the
toolchain automatically.
Reported-by: Mark Brown <broonie@kernel.org>
Closes: https://lore.kernel.org/lkml/af553c62-ca2f-4956-932c-dd6e3a126f58@sirena.org.uk/
Fixes: c9fbaa879508 ("selftests: vDSO: parse_vdso: Use UAPI headers instead of libc headers")
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Link: https://patch.msgid.link/20250321-uapi-consistency-v1-1-439070118dc0@linutronix.de
Signed-off-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull turbostat updates from Len Brown:
- support up to 8192 processors
- add cpuidle governor debug telemetry, disabled by default
- update default output to exclude cpuidle invocation counts
- bug fixes
* tag 'turbostat-2025.05.06' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux:
tools/power turbostat: v2025.05.06
tools/power turbostat: disable "cpuidle" invocation counters, by default
tools/power turbostat: re-factor sysfs code
tools/power turbostat: Restore GFX sysfs fflush() call
tools/power turbostat: Document GNR UncMHz domain convention
tools/power turbostat: report CoreThr per measurement interval
tools/power turbostat: Increase CPU_SUBSET_MAXCPUS to 8192
tools/power turbostat: Add idle governor statistics reporting
tools/power turbostat: Fix names matching
tools/power turbostat: Allow Zero return value for some RAPL registers
tools/power turbostat: Clustered Uncore MHz counters should honor show/hide options
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