Hi, all We hit IO error on fsync, it turns out was because sd treat succeeded SYNC as error. From what I checked in SBC spec there is no indication we should fail IO in this case, so we create this patch. Best Regards, Jack Wang
From 5d1f72d9643ce61cd9f3d312377378c43f171d0c Mon Sep 17 00:00:00 2001 From: Jack Wang <jinpu.wang@xxxxxxxxxxxxxxxx> Date: Mon, 25 Apr 2016 12:05:22 +0200 Subject: [PATCH] sd: Don't treat succeeded SYNC as error We hit IO error in our production on multipath devices during resize device on target side, the problem turns out sd driver passes up as IO error when sense data is UNIT_ATTENTION and ASC && ASCQ indicate Capacity data has changed, even storage side sync the data properly. In order to fix this check in sd_done, report success if condition matches. Sebastian Parschauer report/analyze the bug here: https://sourceforge.net/p/scst/mailman/message/34953416/ Signed-off-by: Sebastian Parschauer <s.parschauer@xxxxxx> Signed-off-by: Jack Wang <jinpu.wang@xxxxxxxxxxxxxxxx> --- drivers/scsi/sd.c | 13 +++++++++++++ 1 file changed, 13 insertions(+) diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c index 5a5457a..e9bfe01 100644 --- a/drivers/scsi/sd.c +++ b/drivers/scsi/sd.c @@ -1833,6 +1833,19 @@ static int sd_done(struct scsi_cmnd *SCpnt) } } break; + case UNIT_ATTENTION: + /* Capacity data has changed */ + if (sshdr.asc == 0x2a && sshdr.ascq == 0x09) { + switch (op) { + /* don't treat succeeded fsync() as error */ + case SYNCHRONIZE_CACHE: + case SYNCHRONIZE_CACHE_16: + if (good_bytes == scsi_bufflen(SCpnt)) + SCpnt->result = 0; + break; + } + } + break; default: break; } -- 1.9.1
