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| author | Bart Van Assche <bvanassche@acm.org> | 2021-12-04 02:19:42 +0300 |
|---|---|---|
| committer | Martin K. Petersen <martin.petersen@oracle.com> | 2021-12-07 06:30:33 +0300 |
| commit | 945c3cca05d78351bba29fa65d93834cb7934c7b (patch) | |
| tree | 1ec62b11efbd064b2feaa35c677f128176c7da44 /drivers/scsi/ufs/ufshcd.h | |
| parent | fc21da8a840a93fd3512e5d779cbb0996cc1b4f1 (diff) | |
| download | linux-945c3cca05d78351bba29fa65d93834cb7934c7b.tar.xz | |
scsi: ufs: Fix a deadlock in the error handler
The following deadlock has been observed on a test setup:
- All tags allocated
- The SCSI error handler calls ufshcd_eh_host_reset_handler()
- ufshcd_eh_host_reset_handler() queues work that calls
ufshcd_err_handler()
- ufshcd_err_handler() locks up as follows:
Workqueue: ufs_eh_wq_0 ufshcd_err_handler.cfi_jt
Call trace:
__switch_to+0x298/0x5d8
__schedule+0x6cc/0xa94
schedule+0x12c/0x298
blk_mq_get_tag+0x210/0x480
__blk_mq_alloc_request+0x1c8/0x284
blk_get_request+0x74/0x134
ufshcd_exec_dev_cmd+0x68/0x640
ufshcd_verify_dev_init+0x68/0x35c
ufshcd_probe_hba+0x12c/0x1cb8
ufshcd_host_reset_and_restore+0x88/0x254
ufshcd_reset_and_restore+0xd0/0x354
ufshcd_err_handler+0x408/0xc58
process_one_work+0x24c/0x66c
worker_thread+0x3e8/0xa4c
kthread+0x150/0x1b4
ret_from_fork+0x10/0x30
Fix this lockup by making ufshcd_exec_dev_cmd() allocate a reserved
request.
Link: https://lore.kernel.org/r/20211203231950.193369-10-bvanassche@acm.org
Tested-by: Bean Huo <beanhuo@micron.com>
Reviewed-by: Adrian Hunter <adrian.hunter@intel.com>
Reviewed-by: Bean Huo <beanhuo@micron.com>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Diffstat (limited to 'drivers/scsi/ufs/ufshcd.h')
| -rw-r--r-- | drivers/scsi/ufs/ufshcd.h | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/drivers/scsi/ufs/ufshcd.h b/drivers/scsi/ufs/ufshcd.h index ecc6c545a19d..c3c2792f309f 100644 --- a/drivers/scsi/ufs/ufshcd.h +++ b/drivers/scsi/ufs/ufshcd.h @@ -745,6 +745,7 @@ struct ufs_hba_monitor { * @capabilities: UFS Controller Capabilities * @nutrs: Transfer Request Queue depth supported by controller * @nutmrs: Task Management Queue depth supported by controller + * @reserved_slot: Used to submit device commands. Protected by @dev_cmd.lock. * @ufs_version: UFS Version to which controller complies * @vops: pointer to variant specific operations * @priv: pointer to variant specific private data @@ -836,6 +837,7 @@ struct ufs_hba { u32 capabilities; int nutrs; int nutmrs; + u32 reserved_slot; u32 ufs_version; const struct ufs_hba_variant_ops *vops; struct ufs_hba_variant_params *vps; |