From 32c356d76d7e13dcd0675189d8e9c64ef66aa561 Mon Sep 17 00:00:00 2001 From: James Bottomley Date: Wed, 20 Aug 2008 00:58:13 +0200 Subject: [PATCH 1/1] [SCSI] fix removable device inability to detect disk changes On Tue, 12 Aug 2008 15:08:14 +0200 Giuliano Pochini wrote: > Fujitsu magneto-optical drive, Adaptec 29160 and > Linux Jay 2.6.26 #7 SMP Sun Aug 10 18:34:22 CEST 2008 ppc 7455, altivec supported PowerMac3,6 GNU/Linux > > When I insert a disk and I mount it, scsi_test_unit_ready() is called and > the do-while loop gets sshdr->sense_key == UNIT_ATTENTION in the first > cycle and 0 in the second one. So the if below misses the UNIT_ATTENTION > and sdev->changed = 1 is not executed. At this point bad things can > happen... I'm not sure how to fix this. Any clue ? The problem is essentially caused by us eating UNIT_ATTENTION conditions in scsi_test_unit_ready(). Fix by updating the ->changed flag when this happens if the media is removable. [pochini@shiny.it: updates to tidy up patch] Signed-off-by: Giuliano Pochini Signed-off-by: James Bottomley --- drivers/scsi/scsi_lib.c | 21 ++++++++++----------- 1 file changed, 10 insertions(+), 11 deletions(-) diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c index e5a9526d203..f35a0951e46 100644 --- a/drivers/scsi/scsi_lib.c +++ b/drivers/scsi/scsi_lib.c @@ -2105,22 +2105,21 @@ scsi_test_unit_ready(struct scsi_device *sdev, int timeout, int retries, do { result = scsi_execute_req(sdev, cmd, DMA_NONE, NULL, 0, sshdr, timeout, retries); - } while ((driver_byte(result) & DRIVER_SENSE) && - sshdr && sshdr->sense_key == UNIT_ATTENTION && - --retries); + if (sdev->removable && scsi_sense_valid(sshdr) && + sshdr->sense_key == UNIT_ATTENTION) + sdev->changed = 1; + } while (scsi_sense_valid(sshdr) && + sshdr->sense_key == UNIT_ATTENTION && --retries); if (!sshdr) /* could not allocate sense buffer, so can't process it */ return result; - if ((driver_byte(result) & DRIVER_SENSE) && sdev->removable) { - - if ((scsi_sense_valid(sshdr)) && - ((sshdr->sense_key == UNIT_ATTENTION) || - (sshdr->sense_key == NOT_READY))) { - sdev->changed = 1; - result = 0; - } + if (sdev->removable && scsi_sense_valid(sshdr) && + (sshdr->sense_key == UNIT_ATTENTION || + sshdr->sense_key == NOT_READY)) { + sdev->changed = 1; + result = 0; } if (!sshdr_external) kfree(sshdr); -- 2.41.1