From: Fenghua Yu Date: Tue, 30 Jan 2024 01:39:54 +0000 (-0800) Subject: dmaengine: idxd: Avoid unnecessary destruction of file_ida X-Git-Tag: v6.10-rc1~72^2~3 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=76e43fa6a456787bad31b8d0daeabda27351a480;p=thirdparty%2Flinux.git dmaengine: idxd: Avoid unnecessary destruction of file_ida 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 --- diff --git a/drivers/dma/idxd/cdev.c b/drivers/dma/idxd/cdev.c index a4b771781afcd..27ddb00cc7a43 100644 --- a/drivers/dma/idxd/cdev.c +++ b/drivers/dma/idxd/cdev.c @@ -501,7 +501,6 @@ 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));