From 3bd6f43f5cb3714f70c591514f344389df593501 Mon Sep 17 00:00:00 2001 From: Bart Van Assche Date: Mon, 4 Dec 2017 10:06:23 -0800 Subject: scsi: core: Ensure that the SCSI error handler gets woken up If scsi_eh_scmd_add() is called concurrently with scsi_host_queue_ready() while shost->host_blocked > 0 then it can happen that neither function wakes up the SCSI error handler. Fix this by making every function that decreases the host_busy counter wake up the error handler if necessary and by protecting the host_failed checks with the SCSI host lock. Reported-by: Pavel Tikhomirov References: https://marc.info/?l=linux-kernel&m=150461610630736 Fixes: commit 746650160866 ("scsi: convert host_busy to atomic_t") Signed-off-by: Bart Van Assche Reviewed-by: Pavel Tikhomirov Tested-by: Stuart Hayes Cc: Konstantin Khorenko Cc: Stuart Hayes Cc: Pavel Tikhomirov Cc: Christoph Hellwig Cc: Hannes Reinecke Cc: Johannes Thumshirn Cc: Signed-off-by: Martin K. Petersen --- include/scsi/scsi_host.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'include/scsi') diff --git a/include/scsi/scsi_host.h b/include/scsi/scsi_host.h index a8b7bf879ced..1a1df0d21ee3 100644 --- a/include/scsi/scsi_host.h +++ b/include/scsi/scsi_host.h @@ -571,6 +571,8 @@ struct Scsi_Host { struct blk_mq_tag_set tag_set; }; + struct rcu_head rcu; + atomic_t host_busy; /* commands actually active on low-level */ atomic_t host_blocked; -- cgit v1.2.3-55-g7522