This is a note to let you know that I've just added the patch titled scsi: ufs: Fix unbalanced scsi_block_reqs_cnt caused by ufshcd_hold() to the 4.19-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: scsi-ufs-fix-unbalanced-scsi_block_reqs_cnt-caused-b.patch and it can be found in the queue-4.19 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit c1c983ddaca745f98a2f3db1ffba060fa164c6d7 Author: Can Guo <cang@xxxxxxxxxxxxxx> Date: Mon Nov 2 22:24:39 2020 -0800 scsi: ufs: Fix unbalanced scsi_block_reqs_cnt caused by ufshcd_hold() [ Upstream commit da3fecb0040324c08f1587e5bff1f15f36be1872 ] The scsi_block_reqs_cnt increased in ufshcd_hold() is supposed to be decreased back in ufshcd_ungate_work() in a paired way. However, if specific ufshcd_hold/release sequences are met, it is possible that scsi_block_reqs_cnt is increased twice but only one ungate work is queued. To make sure scsi_block_reqs_cnt is handled by ufshcd_hold() and ufshcd_ungate_work() in a paired way, increase it only if queue_work() returns true. Link: https://lore.kernel.org/r/1604384682-15837-2-git-send-email-cang@xxxxxxxxxxxxxx Reviewed-by: Hongwu Su <hongwus@xxxxxxxxxxxxxx> Reviewed-by: Stanley Chu <stanley.chu@xxxxxxxxxxxx> Reviewed-by: Bean Huo <beanhuo@xxxxxxxxxx> Signed-off-by: Can Guo <cang@xxxxxxxxxxxxxx> Signed-off-by: Martin K. Petersen <martin.petersen@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c index b2cbdd01ab10b..a63119c35fde8 100644 --- a/drivers/scsi/ufs/ufshcd.c +++ b/drivers/scsi/ufs/ufshcd.c @@ -1592,12 +1592,12 @@ int ufshcd_hold(struct ufs_hba *hba, bool async) * work and to enable clocks. */ case CLKS_OFF: - ufshcd_scsi_block_requests(hba); hba->clk_gating.state = REQ_CLKS_ON; trace_ufshcd_clk_gating(dev_name(hba->dev), hba->clk_gating.state); - queue_work(hba->clk_gating.clk_gating_workq, - &hba->clk_gating.ungate_work); + if (queue_work(hba->clk_gating.clk_gating_workq, + &hba->clk_gating.ungate_work)) + ufshcd_scsi_block_requests(hba); /* * fall through to check if we should wait for this * work to be done or not.