From 7926d51f73e0434a6250c2fd1a0555f98d9a62da Mon Sep 17 00:00:00 2001 From: "Martin K. Petersen" Date: Tue, 4 Jun 2024 22:25:21 -0400 Subject: [PATCH] scsi: sd: Use READ(16) when reading block zero on large capacity disks Commit 321da3dc1f3c ("scsi: sd: usb_storage: uas: Access media prior to querying device properties") triggered a read to LBA 0 before attempting to inquire about device characteristics. This was done because some protocol bridge devices will return generic values until an attached storage device's media has been accessed. Pierre Tomon reported that this change caused problems on a large capacity external drive connected via a bridge device. The bridge in question does not appear to implement the READ(10) command. Issue a READ(16) instead of READ(10) when a device has been identified as preferring 16-byte commands (use_16_for_rw heuristic). Link: https://bugzilla.kernel.org/show_bug.cgi?id=218890 Link: https://lore.kernel.org/r/70dd7ae0-b6b1-48e1-bb59-53b7c7f18274@rowland.harvard.edu Link: https://lore.kernel.org/r/20240605022521.3960956-1-martin.petersen@oracle.com Fixes: 321da3dc1f3c ("scsi: sd: usb_storage: uas: Access media prior to querying device properties") Cc: stable@vger.kernel.org Reported-by: Pierre Tomon Suggested-by: Alan Stern Tested-by: Pierre Tomon Reviewed-by: Bart Van Assche Signed-off-by: Martin K. Petersen --- drivers/scsi/sd.c | 17 ++++++++++++----- 1 file changed, 12 insertions(+), 5 deletions(-) diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c index 332eb9dac22d..fbc11046bbf6 100644 --- a/drivers/scsi/sd.c +++ b/drivers/scsi/sd.c @@ -3565,16 +3565,23 @@ static bool sd_validate_opt_xfer_size(struct scsi_disk *sdkp, static void sd_read_block_zero(struct scsi_disk *sdkp) { - unsigned int buf_len = sdkp->device->sector_size; - char *buffer, cmd[10] = { }; + struct scsi_device *sdev = sdkp->device; + unsigned int buf_len = sdev->sector_size; + u8 *buffer, cmd[16] = { }; buffer = kmalloc(buf_len, GFP_KERNEL); if (!buffer) return; - cmd[0] = READ_10; - put_unaligned_be32(0, &cmd[2]); /* Logical block address 0 */ - put_unaligned_be16(1, &cmd[7]); /* Transfer 1 logical block */ + if (sdev->use_16_for_rw) { + cmd[0] = READ_16; + put_unaligned_be64(0, &cmd[2]); /* Logical block address 0 */ + put_unaligned_be32(1, &cmd[10]);/* Transfer 1 logical block */ + } else { + cmd[0] = READ_10; + put_unaligned_be32(0, &cmd[2]); /* Logical block address 0 */ + put_unaligned_be16(1, &cmd[7]); /* Transfer 1 logical block */ + } scsi_execute_cmd(sdkp->device, cmd, REQ_OP_DRV_IN, buffer, buf_len, SD_TIMEOUT, sdkp->max_retries, NULL);