6.9-stable review patch. If anyone has any objections, please let me know.
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From: Fenghua Yu fenghua.yu@intel.com
[ 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 lijun.pan@intel.com Signed-off-by: Fenghua Yu fenghua.yu@intel.com Reviewed-by: Dave Jiang dave.jiang@intel.com Link: https://lore.kernel.org/r/20240130013954.2024231-1-fenghua.yu@intel.com Signed-off-by: Vinod Koul vkoul@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/dma/idxd/cdev.c | 1 - 1 file changed, 1 deletion(-)
diff --git a/drivers/dma/idxd/cdev.c b/drivers/dma/idxd/cdev.c index 39935071174a3..fd9bbee4cc42f 100644 --- a/drivers/dma/idxd/cdev.c +++ b/drivers/dma/idxd/cdev.c @@ -577,7 +577,6 @@ void idxd_wq_del_cdev(struct idxd_wq *wq) struct idxd_cdev *idxd_cdev;
idxd_cdev = wq->idxd_cdev; - ida_destroy(&file_ida); wq->idxd_cdev = NULL; cdev_device_del(&idxd_cdev->cdev, cdev_dev(idxd_cdev)); put_device(cdev_dev(idxd_cdev));