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 <hare@xxxxxxx> Reviewed-by: Christoph Hellwig <hch@xxxxxxxxxxxxx> Reviewed-by: Ewan Milne <emilne@xxxxxxxxxx> --- 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 8564bdc..a02f7b0 100644 --- a/drivers/scsi/scsi_scan.c +++ b/drivers/scsi/scsi_scan.c @@ -1235,6 +1235,12 @@ static void scsi_sequential_lun_scan(struct scsi_target *starget, 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 * sparse_lun. diff --git a/include/scsi/scsi_devinfo.h b/include/scsi/scsi_devinfo.h index 447d2d7..8670c04 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 -- 1.7.12.4 -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
