diff options
| author | Stanley Chu <stanley.chu@mediatek.com> | 2023-06-10 10:15:51 +0800 |
|---|---|---|
| committer | Martin K. Petersen <martin.petersen@oracle.com> | 2023-06-16 12:04:30 -0400 |
| commit | 0fef6bb730c490fcdc4347dbd21646d3ffe62cf5 (patch) | |
| tree | 6a2ea645048ab097a43444b9e39d5de622e055ea /include/ufs | |
| parent | e246514ae698813ab1eadb1600aeea0a0c959769 (diff) | |
scsi: ufs: core: mcq: Fix the incorrect OCS value for the device command
In MCQ mode, when a device command uses a hardware queue shared with other
commands, a race condition may occur in the following scenario:
1. A device command is completed in CQx with CQE entry "e".
2. The interrupt handler copies the "cqe" pointer to "hba->dev_cmd.cqe"
and completes "hba->dev_cmd.complete".
3. The "ufshcd_wait_for_dev_cmd()" function is awakened and retrieves the
OCS value from "hba->dev_cmd.cqe".
However, there is a possibility that the CQE entry "e" will be overwritten
by newly completed commands in CQx, resulting in an incorrect OCS value
being received by "ufshcd_wait_for_dev_cmd()".
To avoid this race condition, the OCS value should be immediately copied to
the struct "lrb" of the device command. Then "ufshcd_wait_for_dev_cmd()"
can retrieve the OCS value from the struct "lrb".
Fixes: 57b1c0ef89ac ("scsi: ufs: core: mcq: Add support to allocate multiple queues")
Suggested-by: Can Guo <quic_cang@quicinc.com>
Signed-off-by: Stanley Chu <stanley.chu@mediatek.com>
Link: https://lore.kernel.org/r/20230610021553.1213-2-powen.kao@mediatek.com
Tested-by: Po-Wen Kao <powen.kao@mediatek.com>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Diffstat (limited to 'include/ufs')
| -rw-r--r-- | include/ufs/ufshcd.h | 1 |
1 files changed, 0 insertions, 1 deletions
diff --git a/include/ufs/ufshcd.h b/include/ufs/ufshcd.h index d65c9d07694d..92f073bda405 100644 --- a/include/ufs/ufshcd.h +++ b/include/ufs/ufshcd.h @@ -225,7 +225,6 @@ struct ufs_dev_cmd { struct mutex lock; struct completion *complete; struct ufs_query query; - struct cq_entry *cqe; }; /** |