vt8251 chokes on NCQ commands. Two different disks from different vendors are showing the same symptom and it seems that the windows driver from via doesn't support NCQ either. Disable NCQ support on this controller for the time being. Signed-off-by: Tejun Heo <htejun@xxxxxxxxx> Cc: Aalderd Bouwman <boac@xxxxxxxxxx> Cc: Bastiaan Jacques <b.jacques@xxxxxxxxx> --- diff --git a/drivers/scsi/ahci.c b/drivers/scsi/ahci.c index e261b37..8208546 100644 --- a/drivers/scsi/ahci.c +++ b/drivers/scsi/ahci.c @@ -164,6 +164,7 @@ enum { /* ap->flags bits */ AHCI_FLAG_RESET_NEEDS_CLO = (1 << 24), + AHCI_FLAG_NO_NCQ = (1 << 25), }; struct ahci_cmd_hdr { @@ -277,7 +278,7 @@ static const struct ata_port_info ahci_p .host_flags = ATA_FLAG_SATA | ATA_FLAG_NO_LEGACY | ATA_FLAG_MMIO | ATA_FLAG_PIO_DMA | ATA_FLAG_SKIP_D2H_BSY | - AHCI_FLAG_RESET_NEEDS_CLO, + AHCI_FLAG_RESET_NEEDS_CLO | AHCI_FLAG_NO_NCQ, .pio_mask = 0x1f, /* pio0-4 */ .udma_mask = 0x7f, /* udma0-6 ; FIXME */ .port_ops = &ahci_ops, @@ -1362,7 +1363,8 @@ static int ahci_init_one (struct pci_dev if (rc) goto err_out_hpriv; - if (hpriv->cap & HOST_CAP_NCQ) + if (!(probe_ent->host_flags & AHCI_FLAG_NO_NCQ) && + (hpriv->cap & HOST_CAP_NCQ)) probe_ent->host_flags |= ATA_FLAG_NCQ; ahci_print_info(probe_ent); - : send the line "unsubscribe linux-ide" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html