* [PATCH V2] scsi: ufs: core: Fix synchronization between scsi_unjam_host() and ufshcd_queuecommand()
@ 2021-10-08 8:40 Adrian Hunter
2021-10-08 16:40 ` Asutosh Das (asd)
` (2 more replies)
0 siblings, 3 replies; 4+ messages in thread
From: Adrian Hunter @ 2021-10-08 8:40 UTC (permalink / raw)
To: Martin K . Petersen
Cc: James E . J . Bottomley, Bean Huo, Avri Altman, Alim Akhtar,
Can Guo, Asutosh Das, Bart Van Assche, linux-scsi
The SCSI error handler calls scsi_unjam_host() which can call the queue
function ufshcd_queuecommand() indirectly. The error handler changes the
state to UFSHCD_STATE_RESET while running, but error interrupts that
happen while the error handler is running could change the state to
UFSHCD_STATE_EH_SCHEDULED_NON_FATAL which would allow requests to go
through ufshcd_queuecommand() even though the error handler is running.
Block that hole by checking whether the error handler is in progress.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
---
Changes in V2:
Add comment
drivers/scsi/ufs/ufshcd.c | 12 ++++++++++++
1 file changed, 12 insertions(+)
diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index f34227add27d..29d202207b18 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -2688,7 +2688,19 @@ static int ufshcd_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *cmd)
switch (hba->ufshcd_state) {
case UFSHCD_STATE_OPERATIONAL:
+ break;
case UFSHCD_STATE_EH_SCHEDULED_NON_FATAL:
+ /*
+ * SCSI error handler can call ->queuecommand() while UFS error
+ * handler is in progress. Error interrupts could change the
+ * state from UFSHCD_STATE_RESET to
+ * UFSHCD_STATE_EH_SCHEDULED_NON_FATAL. Prevent requests
+ * being issued in that case.
+ */
+ if (ufshcd_eh_in_progress(hba)) {
+ err = SCSI_MLQUEUE_HOST_BUSY;
+ goto out;
+ }
break;
case UFSHCD_STATE_EH_SCHEDULED_FATAL:
/*
--
2.25.1
^ permalink raw reply related [flat|nested] 4+ messages in thread
* Re: [PATCH V2] scsi: ufs: core: Fix synchronization between scsi_unjam_host() and ufshcd_queuecommand()
2021-10-08 8:40 [PATCH V2] scsi: ufs: core: Fix synchronization between scsi_unjam_host() and ufshcd_queuecommand() Adrian Hunter
@ 2021-10-08 16:40 ` Asutosh Das (asd)
2021-10-12 17:53 ` Martin K. Petersen
2021-10-21 3:42 ` Martin K. Petersen
2 siblings, 0 replies; 4+ messages in thread
From: Asutosh Das (asd) @ 2021-10-08 16:40 UTC (permalink / raw)
To: Adrian Hunter, Martin K . Petersen
Cc: James E . J . Bottomley, Bean Huo, Avri Altman, Alim Akhtar,
Can Guo, Bart Van Assche, linux-scsi
On 10/8/2021 1:40 AM, Adrian Hunter wrote:
> The SCSI error handler calls scsi_unjam_host() which can call the queue
> function ufshcd_queuecommand() indirectly. The error handler changes the
> state to UFSHCD_STATE_RESET while running, but error interrupts that
> happen while the error handler is running could change the state to
> UFSHCD_STATE_EH_SCHEDULED_NON_FATAL which would allow requests to go
> through ufshcd_queuecommand() even though the error handler is running.
> Block that hole by checking whether the error handler is in progress.
>
> Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
> ---
LGTM.
Reviewed-by: Asutosh Das <asutoshd@codeaurora.org>
>
> Changes in V2:
>
> Add comment
>
> drivers/scsi/ufs/ufshcd.c | 12 ++++++++++++
> 1 file changed, 12 insertions(+)
>
> diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
> index f34227add27d..29d202207b18 100644
> --- a/drivers/scsi/ufs/ufshcd.c
> +++ b/drivers/scsi/ufs/ufshcd.c
> @@ -2688,7 +2688,19 @@ static int ufshcd_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *cmd)
>
> switch (hba->ufshcd_state) {
> case UFSHCD_STATE_OPERATIONAL:
> + break;
> case UFSHCD_STATE_EH_SCHEDULED_NON_FATAL:
> + /*
> + * SCSI error handler can call ->queuecommand() while UFS error
> + * handler is in progress. Error interrupts could change the
> + * state from UFSHCD_STATE_RESET to
> + * UFSHCD_STATE_EH_SCHEDULED_NON_FATAL. Prevent requests
> + * being issued in that case.
> + */
> + if (ufshcd_eh_in_progress(hba)) {
> + err = SCSI_MLQUEUE_HOST_BUSY;
> + goto out;
> + }
> break;
> case UFSHCD_STATE_EH_SCHEDULED_FATAL:
> /*
>
--
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
Linux Foundation Collaborative Project
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [PATCH V2] scsi: ufs: core: Fix synchronization between scsi_unjam_host() and ufshcd_queuecommand()
2021-10-08 8:40 [PATCH V2] scsi: ufs: core: Fix synchronization between scsi_unjam_host() and ufshcd_queuecommand() Adrian Hunter
2021-10-08 16:40 ` Asutosh Das (asd)
@ 2021-10-12 17:53 ` Martin K. Petersen
2021-10-21 3:42 ` Martin K. Petersen
2 siblings, 0 replies; 4+ messages in thread
From: Martin K. Petersen @ 2021-10-12 17:53 UTC (permalink / raw)
To: Adrian Hunter
Cc: Martin K . Petersen, James E . J . Bottomley, Bean Huo,
Avri Altman, Alim Akhtar, Can Guo, Asutosh Das, Bart Van Assche,
linux-scsi
Adrian,
> The SCSI error handler calls scsi_unjam_host() which can call the queue
> function ufshcd_queuecommand() indirectly. The error handler changes the
> state to UFSHCD_STATE_RESET while running, but error interrupts that
> happen while the error handler is running could change the state to
> UFSHCD_STATE_EH_SCHEDULED_NON_FATAL which would allow requests to go
> through ufshcd_queuecommand() even though the error handler is running.
> Block that hole by checking whether the error handler is in progress.
Applied to 5.16/scsi-staging, thanks!
--
Martin K. Petersen Oracle Linux Engineering
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [PATCH V2] scsi: ufs: core: Fix synchronization between scsi_unjam_host() and ufshcd_queuecommand()
2021-10-08 8:40 [PATCH V2] scsi: ufs: core: Fix synchronization between scsi_unjam_host() and ufshcd_queuecommand() Adrian Hunter
2021-10-08 16:40 ` Asutosh Das (asd)
2021-10-12 17:53 ` Martin K. Petersen
@ 2021-10-21 3:42 ` Martin K. Petersen
2 siblings, 0 replies; 4+ messages in thread
From: Martin K. Petersen @ 2021-10-21 3:42 UTC (permalink / raw)
To: Adrian Hunter
Cc: Martin K . Petersen, Avri Altman, Alim Akhtar, Bart Van Assche,
Can Guo, James E . J . Bottomley, Bean Huo, linux-scsi,
Asutosh Das
On Fri, 8 Oct 2021 11:40:48 +0300, Adrian Hunter wrote:
> The SCSI error handler calls scsi_unjam_host() which can call the queue
> function ufshcd_queuecommand() indirectly. The error handler changes the
> state to UFSHCD_STATE_RESET while running, but error interrupts that
> happen while the error handler is running could change the state to
> UFSHCD_STATE_EH_SCHEDULED_NON_FATAL which would allow requests to go
> through ufshcd_queuecommand() even though the error handler is running.
> Block that hole by checking whether the error handler is in progress.
>
> [...]
Applied to 5.16/scsi-queue, thanks!
[1/1] scsi: ufs: core: Fix synchronization between scsi_unjam_host() and ufshcd_queuecommand()
https://git.kernel.org/mkp/scsi/c/d489f18ad1fc
--
Martin K. Petersen Oracle Linux Engineering
^ permalink raw reply [flat|nested] 4+ messages in thread
end of thread, other threads:[~2021-10-21 3:44 UTC | newest]
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2021-10-08 8:40 [PATCH V2] scsi: ufs: core: Fix synchronization between scsi_unjam_host() and ufshcd_queuecommand() Adrian Hunter
2021-10-08 16:40 ` Asutosh Das (asd)
2021-10-12 17:53 ` Martin K. Petersen
2021-10-21 3:42 ` Martin K. Petersen
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