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authorPeter Wang <peter.wang@mediatek.com>2024-06-28 10:00:30 +0300
committerMartin K. Petersen <martin.petersen@oracle.com>2024-07-05 06:04:15 +0300
commit74736103fb4123c71bf11fb7a6abe7c884c5269e (patch)
tree94cf66be42b8a9bb66ea865091e16d5963e68352 /drivers/ufs/core
parent9307a998cb9846a2557fdca286997430bee36a2a (diff)
downloadlinux-74736103fb4123c71bf11fb7a6abe7c884c5269e.tar.xz
scsi: ufs: core: Fix ufshcd_abort_one racing issue
When ufshcd_abort_one is racing with the completion ISR, the completed tag of the request's mq_hctx pointer will be set to NULL by ISR. Return success when request is completed by ISR because ufshcd_abort_one does not need to do anything. The racing flow is: Thread A ufshcd_err_handler step 1 ... ufshcd_abort_one ufshcd_try_to_abort_task ufshcd_cmd_inflight(true) step 3 ufshcd_mcq_req_to_hwq blk_mq_unique_tag rq->mq_hctx->queue_num step 5 Thread B ufs_mtk_mcq_intr(cq complete ISR) step 2 scsi_done ... __blk_mq_free_request rq->mq_hctx = NULL; step 4 Below is KE back trace. ufshcd_try_to_abort_task: cmd at tag 41 not pending in the device. ufshcd_try_to_abort_task: cmd at tag=41 is cleared. Aborting tag 41 / CDB 0x28 succeeded Unable to handle kernel NULL pointer dereference at virtual address 0000000000000194 pc : [0xffffffddd7a79bf8] blk_mq_unique_tag+0x8/0x14 lr : [0xffffffddd6155b84] ufshcd_mcq_req_to_hwq+0x1c/0x40 [ufs_mediatek_mod_ise] do_mem_abort+0x58/0x118 el1_abort+0x3c/0x5c el1h_64_sync_handler+0x54/0x90 el1h_64_sync+0x68/0x6c blk_mq_unique_tag+0x8/0x14 ufshcd_err_handler+0xae4/0xfa8 [ufs_mediatek_mod_ise] process_one_work+0x208/0x4fc worker_thread+0x228/0x438 kthread+0x104/0x1d4 ret_from_fork+0x10/0x20 Fixes: 93e6c0e19d5b ("scsi: ufs: core: Clear cmd if abort succeeds in MCQ mode") Suggested-by: Bart Van Assche <bvanassche@acm.org> Signed-off-by: Peter Wang <peter.wang@mediatek.com> Link: https://lore.kernel.org/r/20240628070030.30929-3-peter.wang@mediatek.com Reviewed-by: Bart Van Assche <bvanassche@acm.org> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Diffstat (limited to 'drivers/ufs/core')
-rw-r--r--drivers/ufs/core/ufshcd.c2
1 files changed, 2 insertions, 0 deletions
diff --git a/drivers/ufs/core/ufshcd.c b/drivers/ufs/core/ufshcd.c
index 1b65e6ae4137..46433ecf0c4d 100644
--- a/drivers/ufs/core/ufshcd.c
+++ b/drivers/ufs/core/ufshcd.c
@@ -6456,6 +6456,8 @@ static bool ufshcd_abort_one(struct request *rq, void *priv)
/* Release cmd in MCQ mode if abort succeeds */
if (is_mcq_enabled(hba) && (*ret == 0)) {
hwq = ufshcd_mcq_req_to_hwq(hba, scsi_cmd_to_rq(lrbp->cmd));
+ if (!hwq)
+ return 0;
spin_lock_irqsave(&hwq->cq_lock, flags);
if (ufshcd_cmd_inflight(lrbp->cmd))
ufshcd_release_scsi_cmd(hba, lrbp);