diff options
| author |   Adrian Hunter <adrian.hunter@intel.com> | 2021-11-08 08:48:15 +0200 |
|---|---|---|
| committer |   Martin K. Petersen <martin.petersen@oracle.com> | 2021-11-16 19:42:32 -0500 |
| commit | 5cb37a26355d79ab290220677b1b57d28e99a895 (patch) | |
| tree | 7b722eff8ccd14e96733c06e36404d012f99568e /drivers/scsi | |
| parent | scsi: ufs: core: Fix task management completion timeout race (diff) | |
| download | linux-dev-5cb37a26355d79ab290220677b1b57d28e99a895.tar.xz linux-dev-5cb37a26355d79ab290220677b1b57d28e99a895.zip | |
scsi: ufs: core: Fix another task management completion race
hba->outstanding_tasks, which is read under host_lock spinlock, tells the
interrupt handler what task management tags are in use by the driver. The
doorbell register bits indicate which tags are in use by the hardware. A
doorbell bit that is 0 is because the bit has yet to be set by the driver,
or because the task is complete. It is only possible to disambiguate the 2
cases, if reading/writing the doorbell register is synchronized with
reading/writing hba->outstanding_tasks.
For that reason, reading REG_UTP_TASK_REQ_DOOR_BELL must be done under
spinlock.
Link: https://lore.kernel.org/r/20211108064815.569494-3-adrian.hunter@intel.com
Fixes: f5ef336fd2e4 ("scsi: ufs: core: Fix task management completion")
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Diffstat (limited to 'drivers/scsi')
| -rw-r--r-- | drivers/scsi/ufs/ufshcd.c | 3 |
1 files changed, 1 insertions, 2 deletions
diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c index c18aa9a43f0a..13c09dbd99b9 100644 --- a/drivers/scsi/ufs/ufshcd.c +++ b/drivers/scsi/ufs/ufshcd.c @@ -6453,9 +6453,8 @@ static irqreturn_t ufshcd_tmc_handler(struct ufs_hba *hba) irqreturn_t ret = IRQ_NONE; int tag; - pending = ufshcd_readl(hba, REG_UTP_TASK_REQ_DOOR_BELL); - spin_lock_irqsave(hba->host->host_lock, flags); + pending = ufshcd_readl(hba, REG_UTP_TASK_REQ_DOOR_BELL); issued = hba->outstanding_tasks & ~pending; for_each_set_bit(tag, &issued, hba->nutmrs) { struct request *req = hba->tmf_rqs[tag]; |