Re: [PATCH v5] libata: Add ATA_HORKAGE_NO_NCQ_ON_AMD for Samsung 860 and 870 SSD.
From: Hans de Goede
Date: Thu Sep 02 2021 - 12:07:17 EST
Hi All,
On 9/1/21 5:16 PM, Kate Hsuan wrote:
> Many users are reporting that the Samsung 860 and 870 SSD are having
> various issues when combined with AMD SATA controllers and only
> completely disabling NCQ helps to avoid these issues.
>
> Always disabling NCQ for Samsung 860/870 SSDs regardless of the host
> SATA adapter vendor will cause I/O performance degradation with well
> behaved adapters. To limit the performance impact to AMD adapters,
> introduce the ATA_HORKAGE_NO_NCQ_ON_AMD flag to force disable NCQ
> only for these adapters.
>
> Also, two libata.force parameters (noncqamd and ncqamd) are introduced
> to disable and enable the NCQ for the system which equiped with AMD
> SATA adapter and Samsung 860 and 870 SSDs. The user can determine NCQ
> function to be enabled or disabled according to the demand.
>
> BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=201693
> Signed-off-by: Kate Hsuan <hpa@xxxxxxxxxx>
Thanks, v5 looks good to me, but in the mean time I've also gotten the
first replies to my request to collect PCI-ids on systems having this
issue and it looks like checking for PCI_VENDOR_ID_AMD might not be
the right thing to do.
Tor Vic who has a very recent motherboard which does not show this
issue reports the following pci-ids:
06:00.0 SATA controller [0106]: Advanced Micro Devices, Inc. [AMD] FCH
SATA Controller [AHCI mode] [1022:7901] (rev 51)
07:00.0 SATA controller [0106]: Advanced Micro Devices, Inc. [AMD] FCH
SATA Controller [AHCI mode] [1022:7901] (rev 51)
Where as we now have a bunch of lspci -nn outputs from different motherboard
with the issue from: https://bugzilla.kernel.org/show_bug.cgi?id=201693 :
00:11.0 SATA controller [0106]: Advanced Micro Devices, Inc. [AMD/ATI]
SB7x0/SB8x0/SB9x0 SATA Controller [AHCI mode] [1002:4391] (rev 40)
00:11.0 SATA controller [0106]: Advanced Micro Devices, Inc. [AMD/ATI]
SB7x0/SB8x0/SB9x0 SATA Controller [AHCI mode] [1002:4391] (rev 40)
00:11.0 SATA controller [0106]: Advanced Micro Devices, Inc. [AMD/ATI]
SB7x0/SB8x0/SB9x0 SATA Controller [AHCI mode] [1002:4391] (rev 40)
00:11.0 SATA controller [0106]: Advanced Micro Devices, Inc. [AMD/ATI]
SB7x0/SB8x0/SB9x0 SATA Controller [AHCI mode] [1002:4391]
00:11.0 SATA controller [0106]: Advanced Micro Devices, Inc. [AMD/ATI]
SB7x0/SB8x0/SB9x0 SATA Controller [AHCI mode] [1002:4391]
Notice these are basically all the same; and it seems these are
all from the AMD/ATI period where the motherboars chipset where still
using PCI_VENDOR_ID_ATI as vendor-id.
So it looks like we actually need to disable NCQ for Samsung 860/870
devices when the SATA controller has a vendor-id of PCI_VENDOR_ID_ATI
rather then AMD.
So lets wait a bit for some more info to become available and then
I think we need a v6 with s/AMD/ATI/ (everywhere, also in the name
of the horkage-flag, the cmdline options, etc.).
Regards,
Hans
> ---
> Changes in v5:
> * The libata.force parameters ncqamd and noncqamd are used to enable and
> disable the NCQ for the systems equiped with AMD SATA adapter and
> Samsung 860 and 870 SSDs.
> * The character encoding of the patch comment was fixed.
>
> Changes in v4:
> * A function ata_dev_check_adapter() is added to check the vendor ID of
> the adapter.
> * ATA_HORKAGE_NONCQ_ON_AMD was modified to ATA_HORKAGE_NO_NCQ_ON_AMD to
> align with the naming convention.
> * Commit messages were improved according to reviewer comments.
>
> Changes in v3:
> * ATA_HORKAGE_NONCQ_ON_ASMEDIA_AMD_MARVELL was modified to
> ATA_HORKAGE_NONCQ_ON_AMD.
> * Codes were fixed to completely disable NCQ on AMD controller.
>
> ---
> drivers/ata/libata-core.c | 34 ++++++++++++++++++++++++++++++++--
> include/linux/libata.h | 1 +
> 2 files changed, 33 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
> index 3eda3291952b..e2e900085f99 100644
> --- a/drivers/ata/libata-core.c
> +++ b/drivers/ata/libata-core.c
> @@ -2199,6 +2199,25 @@ static void ata_dev_config_ncq_prio(struct ata_device *dev)
>
> }
>
> +static bool ata_dev_check_adapter(struct ata_device *dev,
> + unsigned short vendor_id)
> +{
> + struct pci_dev *pcidev = NULL;
> + struct device *parent_dev = NULL;
> +
> + for (parent_dev = dev->tdev.parent; parent_dev != NULL;
> + parent_dev = parent_dev->parent) {
> + if (dev_is_pci(parent_dev)) {
> + pcidev = to_pci_dev(parent_dev);
> + if (pcidev->vendor == vendor_id)
> + return true;
> + break;
> + }
> + }
> +
> + return false;
> +}
> +
> static int ata_dev_config_ncq(struct ata_device *dev,
> char *desc, size_t desc_sz)
> {
> @@ -2217,6 +2236,13 @@ static int ata_dev_config_ncq(struct ata_device *dev,
> snprintf(desc, desc_sz, "NCQ (not used)");
> return 0;
> }
> +
> + if (dev->horkage & ATA_HORKAGE_NO_NCQ_ON_AMD &&
> + ata_dev_check_adapter(dev, PCI_VENDOR_ID_AMD)) {
> + snprintf(desc, desc_sz, "NCQ (not used)");
> + return 0;
> + }
> +
> if (ap->flags & ATA_FLAG_NCQ) {
> hdepth = min(ap->scsi_host->can_queue, ATA_MAX_QUEUE);
> dev->flags |= ATA_DFLAG_NCQ;
> @@ -3951,9 +3977,11 @@ static const struct ata_blacklist_entry ata_device_blacklist [] = {
> { "Samsung SSD 850*", NULL, ATA_HORKAGE_NO_NCQ_TRIM |
> ATA_HORKAGE_ZERO_AFTER_TRIM, },
> { "Samsung SSD 860*", NULL, ATA_HORKAGE_NO_NCQ_TRIM |
> - ATA_HORKAGE_ZERO_AFTER_TRIM, },
> + ATA_HORKAGE_ZERO_AFTER_TRIM |
> + ATA_HORKAGE_NO_NCQ_ON_AMD, },
> { "Samsung SSD 870*", NULL, ATA_HORKAGE_NO_NCQ_TRIM |
> - ATA_HORKAGE_ZERO_AFTER_TRIM, },
> + ATA_HORKAGE_ZERO_AFTER_TRIM |
> + ATA_HORKAGE_NO_NCQ_ON_AMD, },
> { "FCCT*M500*", NULL, ATA_HORKAGE_NO_NCQ_TRIM |
> ATA_HORKAGE_ZERO_AFTER_TRIM, },
>
> @@ -6108,6 +6136,8 @@ static int __init ata_parse_force_one(char **cur,
> { "ncq", .horkage_off = ATA_HORKAGE_NONCQ },
> { "noncqtrim", .horkage_on = ATA_HORKAGE_NO_NCQ_TRIM },
> { "ncqtrim", .horkage_off = ATA_HORKAGE_NO_NCQ_TRIM },
> + { "noncqamd", .horkage_on = ATA_HORKAGE_NO_NCQ_ON_AMD },
> + { "ncqamd", .horkage_off = ATA_HORKAGE_NO_NCQ_ON_AMD },
> { "dump_id", .horkage_on = ATA_HORKAGE_DUMP_ID },
> { "pio0", .xfer_mask = 1 << (ATA_SHIFT_PIO + 0) },
> { "pio1", .xfer_mask = 1 << (ATA_SHIFT_PIO + 1) },
> diff --git a/include/linux/libata.h b/include/linux/libata.h
> index 3fcd24236793..ef1417152ecd 100644
> --- a/include/linux/libata.h
> +++ b/include/linux/libata.h
> @@ -422,6 +422,7 @@ enum {
> ATA_HORKAGE_NOTRIM = (1 << 24), /* don't use TRIM */
> ATA_HORKAGE_MAX_SEC_1024 = (1 << 25), /* Limit max sects to 1024 */
> ATA_HORKAGE_MAX_TRIM_128M = (1 << 26), /* Limit max trim size to 128M */
> + ATA_HORKAGE_NO_NCQ_ON_AMD = (1 << 27), /* Disable NCQ on AMD chipset */
>
> /* DMA mask for user DMA control: User visible values; DO NOT
> renumber */
> --
> 2.31.1
>