From: Mike Christie <michaelc@xxxxxxxxxxx> Another day another iSCSI target that cannot handle large IOs. The Synology iSCSI targets report: Block limits VPD page (SBC): Write same no zero (WSNZ): 0 Maximum compare and write length: 0 blocks Optimal transfer length granularity: 0 blocks Maximum transfer length: 0 blocks Optimal transfer length: 0 blocks Maximum prefetch length: 0 blocks Maximum unmap LBA count: 0 Maximum unmap block descriptor count: 0 Optimal unmap granularity: 0 Unmap granularity alignment valid: 0 Unmap granularity alignment: 0 Maximum write same length: 0x0 blocks and the size of the command it can handle seems to depend on how much memory it can allocate at the time. This results in IO errors when handling large IOs. This patch just has us use the old 1024 default sectors for this target by adding it to the scsi blacklist. Reported-by: Ancoron Luciferis <ancoron.luciferis@xxxxxxxxxxxxxx> Signed-off-by: Mike Christie <michaelc@xxxxxxxxxxx> --- drivers/scsi/scsi_devinfo.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/scsi/scsi_devinfo.c b/drivers/scsi/scsi_devinfo.c index 848c7ca..d2a8bdf 100644 --- a/drivers/scsi/scsi_devinfo.c +++ b/drivers/scsi/scsi_devinfo.c @@ -227,6 +227,7 @@ static struct { {"Promise", "VTrak E610f", NULL, BLIST_SPARSELUN | BLIST_NO_RSOC}, {"Promise", "", NULL, BLIST_SPARSELUN}, {"QNAP", "iSCSI Storage", NULL, BLIST_MAX_1024}, + {"SYNOLOGY", "iSCSI Storage", NULL, BLIST_MAX_1024}, {"QUANTUM", "XP34301", "1071", BLIST_NOTQ}, {"REGAL", "CDC-4X", NULL, BLIST_MAX5LUN | BLIST_SINGLELUN}, {"SanDisk", "ImageMate CF-SD1", NULL, BLIST_FORCELUN}, -- 1.8.3.1 -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel