Re: [PATCH v9 8/9] scsi: ufs: Fix a racing problem btw error handler and runtime PM ops

From: Martin K. Petersen
Date: Tue Aug 04 2020 - 21:31:47 EST


> Current IRQ handler blocks scsi requests before scheduling eh_work,
> when error handler calls pm_runtime_get_sync, if ufshcd_suspend/resume
> sends a scsi cmd, most likely the SSU cmd, since scsi requests are
> blocked, pm_runtime_get_sync() will never return because
> ufshcd_suspend/reusme is blocked by the scsi cmd. Some changes and
> code re-arrangement can be made to resolve it.

CC [M] drivers/scsi/ufs/ufshcd.o
drivers/scsi/ufs/ufshcd.c: In function ‘ufshcd_queuecommand’:
drivers/scsi/ufs/ufshcd.c:2570:6: error: this statement may fall through [-Werror=implicit-fallthrough=]
2570 | if (hba->pm_op_in_progress) {
| ^
drivers/scsi/ufs/ufshcd.c:2575:2: note: here
| ^~~~
cc1: all warnings being treated as errors
make[3]: *** [scripts/ drivers/scsi/ufs/ufshcd.o] Error 1
make[2]: *** [scripts/ drivers/scsi/ufs] Error 2
make[1]: *** [scripts/ drivers/scsi] Error 2
make: *** [Makefile:1764: drivers] Error 2

Martin K. Petersen Oracle Linux Engineering