Ronny reports: https://bugzilla.kernel.org/show_bug.cgi?id=87101 "Since commit 8a4aeec8d "libata/ahci: accommodate tag ordered controllers" the access to the harddisk on the first SATA-port is failing on its first access. The access to the harddisk on the second port is working normal. When reverting the above commit, access to both harddisks is working fine again." Maintain tag ordered submission as the default, but allow sata_sil24 to continue with the old behavior. Cc: <stable@xxxxxxxxxxxxxxx> Cc: Tejun Heo <tj@xxxxxxxxxx> Reported-by: Ronny Hegewald <Ronny.Hegewald@xxxxxxxxx> Signed-off-by: Dan Williams <dan.j.williams@xxxxxxxxx> --- drivers/ata/libata-core.c | 5 ++++- drivers/ata/sata_sil24.c | 2 +- include/linux/libata.h | 1 + 3 files changed, 6 insertions(+), 2 deletions(-) diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c index 5c84fb5c3372..e2085d4b5b93 100644 --- a/drivers/ata/libata-core.c +++ b/drivers/ata/libata-core.c @@ -4748,7 +4748,10 @@ static struct ata_queued_cmd *ata_qc_new(struct ata_port *ap) return NULL; for (i = 0, tag = ap->last_tag + 1; i < max_queue; i++, tag++) { - tag = tag < max_queue ? tag : 0; + if (ap->flags & ATA_FLAG_LOWTAG) + tag = i; + else + tag = tag < max_queue ? tag : 0; /* the last tag is reserved for internal command. */ if (tag == ATA_TAG_INTERNAL) diff --git a/drivers/ata/sata_sil24.c b/drivers/ata/sata_sil24.c index d81b20ddb527..ea655949023f 100644 --- a/drivers/ata/sata_sil24.c +++ b/drivers/ata/sata_sil24.c @@ -246,7 +246,7 @@ enum { /* host flags */ SIL24_COMMON_FLAGS = ATA_FLAG_SATA | ATA_FLAG_PIO_DMA | ATA_FLAG_NCQ | ATA_FLAG_ACPI_SATA | - ATA_FLAG_AN | ATA_FLAG_PMP, + ATA_FLAG_AN | ATA_FLAG_PMP | ATA_FLAG_LOWTAG, SIL24_FLAG_PCIX_IRQ_WOC = (1 << 24), /* IRQ loss errata on PCI-X */ IRQ_STAT_4PORTS = 0xf, diff --git a/include/linux/libata.h b/include/linux/libata.h index 2d182413b1db..aba87a3f60bc 100644 --- a/include/linux/libata.h +++ b/include/linux/libata.h @@ -231,6 +231,7 @@ enum { ATA_FLAG_SW_ACTIVITY = (1 << 22), /* driver supports sw activity * led */ ATA_FLAG_NO_DIPM = (1 << 23), /* host not happy with DIPM */ + ATA_FLAG_LOWTAG = (1 << 24), /* host wants lowest available tag */ /* bits 24:31 of ap->flags are reserved for LLD specific flags */ -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html