kernel/linux.git/drivers/dma/idxd/cdev.c, branch v6.6.133

dmaengine: idxd: Fix freeing the allocated ida too late

2026-04-02T11:07:32+00:00

[ Upstream commit c311f5e9248471a950f0a524c2fd736414d98900 ] It can happen that when the cdev .release() is called, the driver already called ida_destroy(). Move ida_free() to the _del() path. We see with DEBUG_KOBJECT_RELEASE enabled and forcing an early PCI unbind. Fixes: 04922b7445a1 ("dmaengine: idxd: fix cdev setup and free device lifetime issues") Reviewed-by: Dave Jiang Signed-off-by: Vinicius Costa Gomes Link: https://patch.msgid.link/20260121-idxd-fix-flr-on-kernel-queues-v3-v3-9-7ed70658a9d1@intel.com Signed-off-by: Vinod Koul Signed-off-by: Sasha Levin

dmaengine: idxd: Remove usage of the deprecated ida_simple_xx() API

2026-04-02T11:07:32+00:00

[ Upstream commit 1075ee66a8c19bfa375b19c236fd6a22a867f138 ] ida_alloc() and ida_free() should be preferred to the deprecated ida_simple_get() and ida_simple_remove(). This is less verbose. Note that the upper limit of ida_simple_get() is exclusive, but the one of ida_alloc_range() is inclusive. Sothis change allows one more device. MINORMASK is ((1U << MINORBITS) - 1), so allowing MINORMASK as a maximum value makes sense. It is also consistent with other "ida_.*MINORMASK" and "ida_*MINOR()" usages. Signed-off-by: Christophe JAILLET Reviewed-by: Fenghua Yu Acked-by: Lijun Pan Link: https://lore.kernel.org/r/ac991f5f42112fa782a881d391d447529cbc4a23.1702967302.git.christophe.jaillet@wanadoo.fr Signed-off-by: Vinod Koul Stable-dep-of: c311f5e92484 ("dmaengine: idxd: Fix freeing the allocated ida too late") Signed-off-by: Sasha Levin

dmaengine: idxd: Check availability of workqueue allocated by idxd wq driver before using

2025-07-06T09:00:06+00:00

[ Upstream commit 17502e7d7b7113346296f6758324798d536c31fd ] Running IDXD workloads in a container with the /dev directory mounted can trigger a call trace or even a kernel panic when the parent process of the container is terminated. This issue occurs because, under certain configurations, Docker does not properly propagate the mount replica back to the original mount point. In this case, when the user driver detaches, the WQ is destroyed but it still calls destroy_workqueue() attempting to completes all pending work. It's necessary to check wq->wq and skip the drain if it no longer exists. Signed-off-by: Yi Sun Reviewed-by: Dave Jiang Reviewed-by: Anil S Keshavamurthy Link: https://lore.kernel.org/r/20250509000304.1402863-1-yi.sun@intel.com Signed-off-by: Vinod Koul Signed-off-by: Sasha Levin

dmaengine: idxd: cdev: Fix uninitialized use of sva in idxd_cdev_open

2025-06-04T12:42:25+00:00

[ Upstream commit 97994333de2b8062d2df4e6ce0dc65c2dc0f40dc ] 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 Reviewed-by: Dave Jiang Acked-by: Vinicius Costa Gomes Link: https://lore.kernel.org/r/20250410110216.21592-1-purvayeshi550@gmail.com Signed-off-by: Vinod Koul Signed-off-by: Sasha Levin

dmaengine: idxd: Fix ->poll() return value

2025-06-04T12:42:17+00:00

[ Upstream commit ae74cd15ade833adc289279b5c6f12e78f64d4d7 ] The fix to block access from different address space did not return a correct value for ->poll() change. kernel test bot reported that a return value of type __poll_t is expected rather than int. Fix to return POLLNVAL to indicate invalid request. Fixes: 8dfa57aabff6 ("dmaengine: idxd: Fix allowing write() from different address spaces") Reported-by: kernel test robot Closes: https://lore.kernel.org/oe-kbuild-all/202505081851.rwD7jVxg-lkp@intel.com/ Signed-off-by: Dave Jiang Link: https://lore.kernel.org/r/20250508170548.2747425-1-dave.jiang@intel.com Signed-off-by: Vinod Koul Signed-off-by: Sasha Levin

dmaengine: idxd: Fix allowing write() from different address spaces

2025-06-04T12:42:17+00:00

[ Upstream commit 8dfa57aabff625bf445548257f7711ef294cd30e ] 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 Signed-off-by: Dave Jiang Link: https://lore.kernel.org/r/20250421170337.3008875-1-dave.jiang@intel.com Signed-off-by: Vinod Koul Signed-off-by: Sasha Levin

dmaengine: idxd: add wq driver name support for accel-config user tool

2025-06-04T12:42:17+00:00

[ Upstream commit 7af1e0aceeb321cbc90fcf6fa0bec8870290377f ] With the possibility of multiple wq drivers that can be bound to the wq, the user config tool accel-config needs a way to know which wq driver to bind to the wq. Introduce per wq driver_name sysfs attribute where the user can indicate the driver to be bound to the wq. This allows accel-config to just bind to the driver using wq->driver_name. Signed-off-by: Dave Jiang Signed-off-by: Tom Zanussi Reviewed-by: Fenghua Yu Acked-by: Vinod Koul Link: https://lore.kernel.org/r/20230908201045.4115614-1-fenghua.yu@intel.com Signed-off-by: Vinod Koul Stable-dep-of: 8dfa57aabff6 ("dmaengine: idxd: Fix allowing write() from different address spaces") Signed-off-by: Sasha Levin

dmaengine: idxd: Avoid unnecessary destruction of file_ida

2024-06-12T09:12:25+00:00

[ Upstream commit 76e43fa6a456787bad31b8d0daeabda27351a480 ] file_ida is allocated during cdev open and is freed accordingly during cdev release. This sequence is guaranteed by driver file operations. Therefore, there is no need to destroy an already empty file_ida when the WQ cdev is removed. Worse, ida_free() in cdev release may happen after destruction of file_ida per WQ cdev. This can lead to accessing an id in file_ida after it has been destroyed, resulting in a kernel panic. Remove ida_destroy(&file_ida) to address these issues. Fixes: e6fd6d7e5f0f ("dmaengine: idxd: add a device to represent the file opened") Signed-off-by: Lijun Pan Signed-off-by: Fenghua Yu Reviewed-by: Dave Jiang Link: https://lore.kernel.org/r/20240130013954.2024231-1-fenghua.yu@intel.com Signed-off-by: Vinod Koul Signed-off-by: Sasha Levin

dmaengine: idxd: add a write() method for applications to submit work

2024-05-17T10:02:39+00:00

commit 6827738dc684a87ad54ebba3ae7f3d7c977698eb upstream. After the patch to restrict the use of mmap() to CAP_SYS_RAWIO for the currently existing devices, most applications can no longer make use of the accelerators as in production "you don't run things as root". To keep the DSA and IAA accelerators usable, hook up a write() method so that applications can still submit work. In the write method, sufficient input validation is performed to avoid the security issue that required the mmap CAP_SYS_RAWIO check. One complication is that the DSA device allows for indirect ("batched") descriptors. There is no reasonable way to do the input validation on these indirect descriptors so the write() method will not allow these to be submitted to the hardware on affected hardware, and the sysfs enumeration of support for the opcode is also removed. Early performance data shows that the performance delta for most common cases is within the noise. Signed-off-by: Nikhil Rao Signed-off-by: Arjan van de Ven Signed-off-by: Greg Kroah-Hartman

dmaengine: idxd: add a new security check to deal with a hardware erratum

2024-05-17T10:02:38+00:00

commit e11452eb071b2a8e6ba52892b2e270bbdaa6640d upstream. On Sapphire Rapids and related platforms, the DSA and IAA devices have an erratum that causes direct access (for example, by using the ENQCMD or MOVDIR64 instructions) from untrusted applications to be a security problem. To solve this, add a flag to the PCI device enumeration and device structures to indicate the presence/absence of this security exposure. In the mmap() method of the device, this flag is then used to enforce that the user has the CAP_SYS_RAWIO capability. In a future patch, a write() based method will be added that allows untrusted applications submit work to the accelerator, where the kernel can do sanity checking on the user input to ensure secure operation of the accelerator. Signed-off-by: Arjan van de Ven Signed-off-by: Greg Kroah-Hartman