4.4-stable review patch. If anyone has any objections, please let me know.
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From: Maya Erez merez@codeaurora.org
[ Upstream commit 2e3611e9546c2ed4def152a51dfd34e8dddae7a5 ]
The device can set the exception event bit in one of the response UPIU, for example to notify the need for urgent BKOPs operation. In such a case, the host driver calls ufshcd_exception_event_handler to handle this notification. When trying to check the exception event status (for finding the cause for the exception event), the device may be busy with additional SCSI commands handling and may not respond within the 100ms timeout.
To prevent that, we need to block SCSI commands during handling of exception events and allow retransmissions of the query requests, in case of timeout.
Signed-off-by: Subhash Jadavani subhashj@codeaurora.org Signed-off-by: Maya Erez merez@codeaurora.org Signed-off-by: Can Guo cang@codeaurora.org Signed-off-by: Asutosh Das asutoshd@codeaurora.org Reviewed-by: Subhash Jadavani subhashj@codeaurora.org Signed-off-by: Martin K. Petersen martin.petersen@oracle.com Signed-off-by: Sasha Levin alexander.levin@microsoft.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/scsi/ufs/ufshcd.c | 2 ++ 1 file changed, 2 insertions(+)
--- a/drivers/scsi/ufs/ufshcd.c +++ b/drivers/scsi/ufs/ufshcd.c @@ -3447,6 +3447,7 @@ static void ufshcd_exception_event_handl hba = container_of(work, struct ufs_hba, eeh_work);
pm_runtime_get_sync(hba->dev); + scsi_block_requests(hba->host); err = ufshcd_get_ee_status(hba, &status); if (err) { dev_err(hba->dev, "%s: failed to get exception status %d\n", @@ -3462,6 +3463,7 @@ static void ufshcd_exception_event_handl __func__, err); } out: + scsi_unblock_requests(hba->host); pm_runtime_put_sync(hba->dev); return; }