From e73a5e8e8003978e65d368f5475e36e1e2a0613b Mon Sep 17 00:00:00 2001 From: Hannes Reinecke Date: Mon, 22 Jun 2020 08:30:22 +0200 Subject: [PATCH] scsi: core: Only return started requests from scsi_host_find_tag() scsi_host_find_tag() is used by the drivers to return a scsi command based on the command tag. Typically it's used from the interrupt handler to fetch the command associated with a value returned from hardware. Some drivers like fnic or qla4xxx, however, also use it also to traverse outstanding commands. With the current implementation scsi_host_find_tag() will return commands even if they are not started (i.e. passed to the driver). This will result in random errors with those drivers. With this patch scsi_host_find_tag() will only return 'started' commands (i.e. commands which have been passed to the drivers) thus avoiding the above issue. The other use cases will be unaffected as the interrupt handler naturally will only ever return 'started' requests. Link: https://lore.kernel.org/r/20200622063022.67891-1-hare@suse.de Signed-off-by: Hannes Reinecke Signed-off-by: Martin K. Petersen --- include/scsi/scsi_tcq.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/include/scsi/scsi_tcq.h b/include/scsi/scsi_tcq.h index 6053d46e794e..ea7848e74d25 100644 --- a/include/scsi/scsi_tcq.h +++ b/include/scsi/scsi_tcq.h @@ -34,7 +34,7 @@ static inline struct scsi_cmnd *scsi_host_find_tag(struct Scsi_Host *shost, blk_mq_unique_tag_to_tag(tag)); } - if (!req) + if (!req || !blk_mq_request_started(req)) return NULL; return blk_mq_rq_to_pdu(req); }