From b92f44353fdc526df58a563a6c9279293eb607c7 Mon Sep 17 00:00:00 2001 From: Hannes Reinecke Date: Fri, 15 Jan 2010 13:07:34 +0100 Subject: aic79xx: check for non-NULL scb in ahd_handle_nonpkt_busfree commit 534ef056db8a8fb6b9d50188d88ed5d1fbc66673 upstream. When removing several devices aic79xx will occasionally Oops in ahd_handle_nonpkt_busfree during rescan. Looking at the code I found that we're indeed not checking if the scb in question is NULL. So check for it before accessing it. Signed-off-by: Hannes Reinecke Signed-off-by: James Bottomley Signed-off-by: Greg Kroah-Hartman --- drivers/scsi/aic7xxx/aic79xx_core.c | 53 ++++++++++++++++++++++--------------- 1 file changed, 31 insertions(+), 22 deletions(-) diff --git a/drivers/scsi/aic7xxx/aic79xx_core.c b/drivers/scsi/aic7xxx/aic79xx_core.c index 63b521d615f2..3e89f8e06cbc 100644 --- a/drivers/scsi/aic7xxx/aic79xx_core.c +++ b/drivers/scsi/aic7xxx/aic79xx_core.c @@ -3171,13 +3171,16 @@ ahd_handle_nonpkt_busfree(struct ahd_softc *ahd) tinfo->curr.transport_version = 2; tinfo->goal.transport_version = 2; tinfo->goal.ppr_options = 0; - /* - * Remove any SCBs in the waiting for selection - * queue that may also be for this target so - * that command ordering is preserved. - */ - ahd_freeze_devq(ahd, scb); - ahd_qinfifo_requeue_tail(ahd, scb); + if (scb != NULL) { + /* + * Remove any SCBs in the waiting + * for selection queue that may + * also be for this target so that + * command ordering is preserved. + */ + ahd_freeze_devq(ahd, scb); + ahd_qinfifo_requeue_tail(ahd, scb); + } printerror = 0; } } else if (ahd_sent_msg(ahd, AHDMSG_EXT, MSG_EXT_WDTR, FALSE) @@ -3194,13 +3197,16 @@ ahd_handle_nonpkt_busfree(struct ahd_softc *ahd) MSG_EXT_WDTR_BUS_8_BIT, AHD_TRANS_CUR|AHD_TRANS_GOAL, /*paused*/TRUE); - /* - * Remove any SCBs in the waiting for selection - * queue that may also be for this target so that - * command ordering is preserved. - */ - ahd_freeze_devq(ahd, scb); - ahd_qinfifo_requeue_tail(ahd, scb); + if (scb != NULL) { + /* + * Remove any SCBs in the waiting for + * selection queue that may also be for + * this target so that command ordering + * is preserved. + */ + ahd_freeze_devq(ahd, scb); + ahd_qinfifo_requeue_tail(ahd, scb); + } printerror = 0; } else if (ahd_sent_msg(ahd, AHDMSG_EXT, MSG_EXT_SDTR, FALSE) && ppr_busfree == 0) { @@ -3217,13 +3223,16 @@ ahd_handle_nonpkt_busfree(struct ahd_softc *ahd) /*ppr_options*/0, AHD_TRANS_CUR|AHD_TRANS_GOAL, /*paused*/TRUE); - /* - * Remove any SCBs in the waiting for selection - * queue that may also be for this target so that - * command ordering is preserved. - */ - ahd_freeze_devq(ahd, scb); - ahd_qinfifo_requeue_tail(ahd, scb); + if (scb != NULL) { + /* + * Remove any SCBs in the waiting for + * selection queue that may also be for + * this target so that command ordering + * is preserved. + */ + ahd_freeze_devq(ahd, scb); + ahd_qinfifo_requeue_tail(ahd, scb); + } printerror = 0; } else if ((ahd->msg_flags & MSG_FLAG_EXPECT_IDE_BUSFREE) != 0 && ahd_sent_msg(ahd, AHDMSG_1B, @@ -3251,7 +3260,7 @@ ahd_handle_nonpkt_busfree(struct ahd_softc *ahd) * the message phases. We check it last in case we * had to send some other message that caused a busfree. */ - if (printerror != 0 + if (scb != NULL && printerror != 0 && (lastphase == P_MESGIN || lastphase == P_MESGOUT) && ((ahd->msg_flags & MSG_FLAG_EXPECT_PPR_BUSFREE) != 0)) { -- cgit v1.2.3