scsi: ufs: core: Don't perform UFS clkscaling during host async scan

[ Upstream commit e97633492f5a3eca7b3ff03b4ef6f993017f7955 ]

When preparing for UFS clock scaling, the UFS driver will quiesce all
sdevs queues in the UFS SCSI host tagset list and then unquiesce them in
ufshcd_clock_scaling_unprepare(). If the UFS SCSI host async scan is in
progress at this time, some LUs may be added to the tagset list between
UFS clkscale prepare and unprepare. This can cause two issues:

1. During clock scaling, there may be I/O requests issued through new
added queues that have not been quiesced, leading to task abort issue.

2. These new added queues that have not been quiesced will be unquiesced
as well when UFS clkscale is unprepared, resulting in warning prints.

Therefore, use the mutex lock scan_mutex in
ufshcd_clock_scaling_prepare() and ufshcd_clock_scaling_unprepare() to
protect it.

Co-developed-by: Can Guo <quic_cang@quicinc.com>
Signed-off-by: Can Guo <quic_cang@quicinc.com>
Signed-off-by: Ziqi Chen <quic_ziqichen@quicinc.com>
Link: https://lore.kernel.org/r/20250522081233.2358565-1-quic_ziqichen@quicinc.com
Suggested-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Ziqi Chen
2025-05-22 16:12:28 +08:00
committed by Greg Kroah-Hartman
parent acc1d4cc47
commit d120737a6d

View File

@@ -1284,6 +1284,7 @@ static int ufshcd_clock_scaling_prepare(struct ufs_hba *hba, u64 timeout_us)
* make sure that there are no outstanding requests when
* clock scaling is in progress
*/
mutex_lock(&hba->host->scan_mutex);
blk_mq_quiesce_tagset(&hba->host->tag_set);
mutex_lock(&hba->wb_mutex);
down_write(&hba->clk_scaling_lock);
@@ -1294,6 +1295,7 @@ static int ufshcd_clock_scaling_prepare(struct ufs_hba *hba, u64 timeout_us)
up_write(&hba->clk_scaling_lock);
mutex_unlock(&hba->wb_mutex);
blk_mq_unquiesce_tagset(&hba->host->tag_set);
mutex_unlock(&hba->host->scan_mutex);
goto out;
}
@@ -1315,6 +1317,7 @@ static void ufshcd_clock_scaling_unprepare(struct ufs_hba *hba, int err, bool sc
mutex_unlock(&hba->wb_mutex);
blk_mq_unquiesce_tagset(&hba->host->tag_set);
mutex_unlock(&hba->host->scan_mutex);
ufshcd_release(hba);
}