From 22ffeb48b7584d6cd50f2a595ed6065d86a87459 Mon Sep 17 00:00:00 2001 From: Hannes Reinecke Date: Tue, 3 Jun 2014 10:58:53 +0200 Subject: [PATCH] scsi_scan: Restrict sequential scan to 256 LUNs Sequential scan for more than 256 LUNs is very fragile as LUNs might not be numbered sequentially after that point. SAM revisions later than SCSI-3 impose a structure on LUNs larger than 256, making LUN numbers between 256 and 16384 illegal. SCSI-3, however allows for plain 64-bit numbers with no internal structure. So restrict sequential LUN scan to 256 LUNs and add a new blacklist flag 'BLIST_SCSI3LUN' to scan up to max_lun devices. Signed-off-by: Hannes Reinecke Reviewed-by: Ewan Milne Signed-off-by: Christoph Hellwig --- drivers/scsi/scsi_scan.c | 6 ++++++ include/scsi/scsi_devinfo.h | 2 ++ 2 files changed, 8 insertions(+) diff --git a/drivers/scsi/scsi_scan.c b/drivers/scsi/scsi_scan.c index 8564bdcd2287..a02f7b0976ed 100644 --- a/drivers/scsi/scsi_scan.c +++ b/drivers/scsi/scsi_scan.c @@ -1234,6 +1234,12 @@ static void scsi_sequential_lun_scan(struct scsi_target *starget, if (scsi_level < SCSI_3 && !(bflags & BLIST_LARGELUN)) max_dev_lun = min(8U, max_dev_lun); + /* + * Stop scanning at 255 unless BLIST_SCSI3LUN + */ + if (!(bflags & BLIST_SCSI3LUN)) + max_dev_lun = min(256U, max_dev_lun); + /* * We have already scanned LUN 0, so start at LUN 1. Keep scanning * until we reach the max, or no LUN is found and we are not diff --git a/include/scsi/scsi_devinfo.h b/include/scsi/scsi_devinfo.h index 447d2d7466fc..8670c04e199e 100644 --- a/include/scsi/scsi_devinfo.h +++ b/include/scsi/scsi_devinfo.h @@ -32,4 +32,6 @@ #define BLIST_ATTACH_PQ3 0x1000000 /* Scan: Attach to PQ3 devices */ #define BLIST_NO_DIF 0x2000000 /* Disable T10 PI (DIF) */ #define BLIST_SKIP_VPD_PAGES 0x4000000 /* Ignore SBC-3 VPD pages */ +#define BLIST_SCSI3LUN 0x8000000 /* Scan more than 256 LUNs + for sequential scan */ #endif -- 2.20.1