From: Eddie Wai Date: Wed, 18 Sep 2013 05:33:10 +0000 (-0700) Subject: [SCSI] bnx2fc: Fixed a SCSI CMD cmpl race condition between ABTS and CLEANUP X-Git-Tag: firefly_0821_release~176^2~4986^2~70 X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=21837896097a6d141c7ac581500ee648c5b4bb89;p=firefly-linux-kernel-4.4.55.git [SCSI] bnx2fc: Fixed a SCSI CMD cmpl race condition between ABTS and CLEANUP In the case when a SCSI_CMD times out, bnx2fc will initiate the sending of the ABTS. However, if the SCSI layer's SCSI command timer also times out, it'll instantiate a task abort of the same xid. The race condition this patch tries to fix is as follows: SCSI_CMD timeout (20s) thread 1 thread 2 send ABTS rx ABTS cmpl task abort_eh explicit LOGO since ABTS was engaged CLEANUP cmpl SCSI_CMD cmpl (ABTS cmpl) instantiate RRQ wait 10s attempt to send RRQ (because of LOGO, it wouldn't continue) Note that there is no call to scsi_done for this SCSI_CMD cmpletion in this path. The patch changes the path of execution to call scsi_done immediately instead of instantiating the RRQ. Signed-off-by: Eddie Wai Signed-off-by: James Bottomley --- diff --git a/drivers/scsi/bnx2fc/bnx2fc_io.c b/drivers/scsi/bnx2fc/bnx2fc_io.c index 575142e92d9c..ed880891cb7c 100644 --- a/drivers/scsi/bnx2fc/bnx2fc_io.c +++ b/drivers/scsi/bnx2fc/bnx2fc_io.c @@ -1246,6 +1246,12 @@ int bnx2fc_eh_abort(struct scsi_cmnd *sc_cmd) kref_put(&io_req->refcount, bnx2fc_cmd_release); /* drop timer hold */ rc = bnx2fc_expl_logo(lport, io_req); + /* This only occurs when an task abort was requested while ABTS + is in progress. Setting the IO_CLEANUP flag will skip the + RRQ process in the case when the fw generated SCSI_CMD cmpl + was a result from the ABTS request rather than the CLEANUP + request */ + set_bit(BNX2FC_FLAG_IO_CLEANUP, &io_req->req_flags); goto out; }