kernel/linux.git/drivers/ata/libata-core.c, branch v6.12.80

ata: libata-core: disable LPM on ADATA SU680 SSD

2026-03-25T10:08:48+00:00

commit ce5ae93d1a216680460040c7c0465a6e3b629dec upstream. ADATA SU680 SSDs suffer from NCQ read and write commands timeouts or bus errors when link power management (LPM) is enabled. Flag these devices with the ATA_QUIRK_NOLPM quirk to prevent the use of LPM and avoid these command failures. Reported-by: Mohammad Khaled Bayan Closes: https://bugs.launchpad.net/ubuntu/+source/linux-hwe-6.17/+bug/2144060 Cc: stable@vger.kernel.org Tested-by: Mohammad-Khaled Bayan Signed-off-by: Damien Le Moal Reviewed-by: Martin K. Petersen Signed-off-by: Niklas Cassel Signed-off-by: Greg Kroah-Hartman

ata: libata-core: Disable LPM on ST1000DM010-2EP102

2026-03-25T10:08:36+00:00

commit b3b1d3ae1d87bc9398fb715c945968bf4c75a09a upstream. According to a user report, the ST1000DM010-2EP102 has problems with LPM, causing random system freezes. The drive belongs to the same BarraCuda family as the ST2000DM008-2FR102 which has the same issue. Cc: stable@vger.kernel.org Fixes: 7627a0edef54 ("ata: ahci: Drop low power policy board type") Reported-by: Filippo Baiamonte Closes: https://bugzilla.kernel.org/show_bug.cgi?id=221163 Signed-off-by: Maximilian Pezzullo Reviewed-by: Damien Le Moal Signed-off-by: Niklas Cassel Signed-off-by: Greg Kroah-Hartman

ata: libata-core: Add BRIDGE_OK quirk for QEMU drives

2026-03-25T10:08:31+00:00

commit b92b0075ee1870f78f59ab1f7da7dbfdd718ad7a upstream. Currently, whenever you boot with a QEMU drive over an AHCI interface, you get: [ 1.632121] ata1.00: applying bridge limits This happens due to the kernel not believing the given drive is SATA, since word 93 of IDENTIFY (ATA_ID_HW_CONFIG) is non-zero. The result is a pretty severe limit in max_hw_sectors_kb, which limits our IO sizes. QEMU has set word 93 erroneously for SATA drives but does not, in any way, emulate any of these real hardware details. There is no PATA drive and no SATA cable. As such, add a BRIDGE_OK quirk for QEMU HARDDISK. Special care is taken to limit this quirk to "2.5+", to allow for fixed future versions. This results in the max_hw_sectors being limited solely by the controller interface's limits. Which, for AHCI controllers, takes it from 128KB to 32767KB. Cc: stable@vger.kernel.org Signed-off-by: Pedro Falcato Reviewed-by: Damien Le Moal Reviewed-by: Hannes Reinecke Signed-off-by: Niklas Cassel Signed-off-by: Greg Kroah-Hartman

ata: libata-core: fix cancellation of a port deferred qc work

2026-03-13T16:20:49+00:00

commit 55db009926634b20955bd8abbee921adbc8d2cb4 upstream. cancel_work_sync() is a sleeping function so it cannot be called with the spin lock of a port being held. Move the call to this function in ata_port_detach() after EH completes, with the port lock released, together with other work cancellation calls. Fixes: 0ea84089dbf6 ("ata: libata-scsi: avoid Non-NCQ command starvation") Signed-off-by: Damien Le Moal Reviewed-by: Hannes Reinecke Reviewed-by: Igor Pylypiv Signed-off-by: Greg Kroah-Hartman

ata: libata-scsi: avoid Non-NCQ command starvation

2026-03-13T16:20:23+00:00

[ Upstream commit 0ea84089dbf62a92dc7889c79e6b18fc89260808 ] When a non-NCQ command is issued while NCQ commands are being executed, ata_scsi_qc_issue() indicates to the SCSI layer that the command issuing should be deferred by returning SCSI_MLQUEUE_XXX_BUSY. This command deferring is correct and as mandated by the ACS specifications since NCQ and non-NCQ commands cannot be mixed. However, in the case of a host adapter using multiple submission queues, when the target device is under a constant load of NCQ commands, there are no guarantees that requeueing the non-NCQ command will be executed later and it may be deferred again repeatedly as other submission queues can constantly issue NCQ commands from different CPUs ahead of the non-NCQ command. This can lead to very long delays for the execution of non-NCQ commands, and even complete starvation for these commands in the worst case scenario. Since the block layer and the SCSI layer do not distinguish between queueable (NCQ) and non queueable (non-NCQ) commands, libata-scsi SAT implementation must ensure forward progress for non-NCQ commands in the presence of NCQ command traffic. This is similar to what SAS HBAs with a hardware/firmware based SAT implementation do. Implement such forward progress guarantee by limiting requeueing of non-NCQ commands from ata_scsi_qc_issue(): when a non-NCQ command is received and NCQ commands are in-flight, do not force a requeue of the non-NCQ command by returning SCSI_MLQUEUE_XXX_BUSY and instead return 0 to indicate that the command was accepted but hold on to the qc using the new deferred_qc field of struct ata_port. This deferred qc will be issued using the work item deferred_qc_work running the function ata_scsi_deferred_qc_work() once all in-flight commands complete, which is checked with the port qc_defer() callback return value indicating that no further delay is necessary. This check is done using the helper function ata_scsi_schedule_deferred_qc() which is called from ata_scsi_qc_complete(). This thus excludes this mechanism from all internal non-NCQ commands issued by ATA EH. When a port deferred_qc is non NULL, that is, the port has a command waiting for the device queue to drain, the issuing of all incoming commands (both NCQ and non-NCQ) is deferred using the regular busy mechanism. This simplifies the code and also avoids potential denial of service problems if a user issues too many non-NCQ commands. Finally, whenever ata EH is scheduled, regardless of the reason, a deferred qc is always requeued so that it can be retried once EH completes. This is done by calling the function ata_scsi_requeue_deferred_qc() from ata_eh_set_pending(). This avoids the need for any special processing for the deferred qc in case of NCQ error, link or device reset, or device timeout. Reported-by: Xingui Yang Reported-by: Igor Pylypiv Fixes: bdb01301f3ea ("scsi: Add host and host template flag 'host_tagset'") Cc: stable@vger.kernel.org Signed-off-by: Damien Le Moal Reviewed-by: Niklas Cassel Reviewed-by: Martin K. Petersen Reviewed-by: John Garry Tested-by: Igor Pylypiv Tested-by: Xingui Yang Signed-off-by: Sasha Levin

ata: libata: Remove ATA_DFLAG_ZAC device flag

2026-03-13T16:20:23+00:00

[ Upstream commit a0f26fcc383965e0522b81269062a9278bc802fe ] The ATA device flag ATA_DFLAG_ZAC is used to indicate if a devie is a host managed or host aware zoned device. However, this flag is not used in the hot path and only used during device scanning/revalidation and for inquiry and sense SCSI command translation. Save one bit from struct ata_device flags field by replacing this flag with the internal helper function ata_dev_is_zac(). This function returns true if the device class is ATA_DEV_ZAC (host managed ZAC device case) or if its identify data reports it supports the zoned command set (host aware ZAC device case). Signed-off-by: Damien Le Moal Reviewed-by: Hannes Reinecke Reviewed-by: Niklas Cassel Stable-dep-of: 0ea84089dbf6 ("ata: libata-scsi: avoid Non-NCQ command starvation") Signed-off-by: Sasha Levin

ata: libata: avoid long timeouts on hot-unplugged SATA DAS

2026-03-04T12:21:20+00:00

[ Upstream commit 151cabd140322205e27dae5c4bbf261ede0056e3 ] When a SATA DAS enclosure is connected behind a Thunderbolt PCIe switch, hot-unplugging the whole enclosure causes pciehp to tear down the PCI hierarchy before the SCSI layer issues SYNCHRONIZE CACHE and START STOP UNIT for the disks. libata still queues these commands and the AHCI driver tries to access the HBA registers even though the PCI channel is already offline. This results in a series of timeouts and error recovery attempts, e.g.: [ 824.778346] pcieport 0000:00:07.0: pciehp: Slot(14): Link Down [ 891.612720] ata8.00: qc timeout after 5000 msecs (cmd 0xec) [ 902.876501] ata8.00: qc timeout after 10000 msecs (cmd 0xec) [ 934.107998] ata8.00: qc timeout after 30000 msecs (cmd 0xec) [ 936.206431] sd 7:0:0:0: [sda] Synchronize Cache(10) failed: Result: hostbyte=DID_BAD_TARGET driverbyte=DRIVER_OK ... [ 1006.298356] ata1.00: qc timeout after 5000 msecs (cmd 0xec) [ 1017.561926] ata1.00: qc timeout after 10000 msecs (cmd 0xec) [ 1048.791790] ata1.00: qc timeout after 30000 msecs (cmd 0xec) [ 1050.890035] sd 0:0:0:0: [sdb] Synchronize Cache(10) failed: Result: hostbyte=DID_BAD_TARGET driverbyte=DRIVER_OK With this patch applied, the same hot-unplug looks like: [ 59.965496] pcieport 0000:00:07.0: pciehp: Slot(14): Link Down [ 60.002502] sd 7:0:0:0: [sda] Synchronize Cache(10) failed: Result: hostbyte=DID_BAD_TARGET driverbyte=DRIVER_OK ... [ 60.103050] sd 0:0:0:0: [sdb] Synchronize Cache(10) failed: Result: hostbyte=DID_BAD_TARGET driverbyte=DRIVER_OK In this test setup with two disks, the hot-unplug sequence shrinks from about 226 seconds (~3.8 minutes) between the Link Down event and the last SYNCHRONIZE CACHE failure to under a second. Without this patch the total delay grows roughly with the number of disks, because each disk gets its own SYNCHRONIZE CACHE and qc timeout series. If the underlying PCI device is already gone, these commands cannot succeed anyway. Avoid issuing them by introducing ata_adapter_is_online(), which checks pci_channel_offline() for PCI-based hosts. It is used from ata_scsi_find_dev() to return NULL, causing the SCSI layer to fail new commands with DID_BAD_TARGET immediately, and from ata_qc_issue() to bail out before touching the HBA registers. Since such failures would otherwise trigger libata error handling, ata_adapter_is_online() is also consulted from ata_scsi_port_error_handler(). When the adapter is offline, libata skips ap->ops->error_handler(ap) and completes error handling using the existing path, rather than running a full EH sequence against a dead adapter. With this change, SYNCHRONIZE CACHE and START STOP UNIT commands issued during hot-unplug fail quickly once the PCI channel is offline, without qc timeout spam or long libata EH delays. Suggested-by: Damien Le Moal Signed-off-by: Henry Tseng Signed-off-by: Damien Le Moal Signed-off-by: Sasha Levin

ata: libata: Print features also for ATAPI devices

2026-01-30T09:28:38+00:00

[ Upstream commit c8c6fb886f57d5bf71fb6de6334a143608d35707 ] Commit d633b8a702ab ("libata: print feature list on device scan") added a print of the features supported by the device for ATA_DEV_ATA and ATA_DEV_ZAC devices, but not for ATA_DEV_ATAPI devices. Fix this by printing the features also for ATAPI devices. Before changes: ata1.00: ATAPI: Slimtype DVD A DU8AESH, 6C2M, max UDMA/133 After changes: ata1.00: ATAPI: Slimtype DVD A DU8AESH, 6C2M, max UDMA/133 ata1.00: Features: Dev-Attention HIPM DIPM Fixes: d633b8a702ab ("libata: print feature list on device scan") Signed-off-by: Niklas Cassel Tested-by: Wolf Signed-off-by: Damien Le Moal Signed-off-by: Sasha Levin

ata: libata: Call ata_dev_config_lpm() for ATAPI devices

2026-01-30T09:28:38+00:00

[ Upstream commit 8f3fb33f8f3f825c708ece800c921977c157f9b6 ] Commit d360121832d8 ("ata: libata-core: Introduce ata_dev_config_lpm()") introduced ata_dev_config_lpm(). However, it only called this function for ATA_DEV_ATA and ATA_DEV_ZAC devices, not for ATA_DEV_ATAPI devices. Additionally, commit d99a9142e782 ("ata: libata-core: Move device LPM quirk settings to ata_dev_config_lpm()") moved the LPM quirk application from ata_dev_configure() to ata_dev_config_lpm(), causing LPM quirks for ATAPI devices to no longer be applied. Call ata_dev_config_lpm() also for ATAPI devices, such that LPM quirks are applied for ATAPI devices with an entry in __ata_dev_quirks once again. Fixes: d360121832d8 ("ata: libata-core: Introduce ata_dev_config_lpm()") Fixes: d99a9142e782 ("ata: libata-core: Move device LPM quirk settings to ata_dev_config_lpm()") Signed-off-by: Niklas Cassel Tested-by: Wolf Signed-off-by: Damien Le Moal Stable-dep-of: c8c6fb886f57 ("ata: libata: Print features also for ATAPI devices") Signed-off-by: Sasha Levin

ata: libata-core: Introduce ata_dev_config_lpm()

2026-01-30T09:28:38+00:00

[ Upstream commit d360121832d8a36871249271df5b9ff05f835f62 ] If the port of a device does not support Device Initiated Power Management (DIPM), that is, the port is flagged with ATA_FLAG_NO_DIPM, the DIPM feature of a device should not be used. Though DIPM is disabled by default on a device, the "Software Settings Preservation feature" may keep DIPM enabled or DIPM may have been enabled by the system firmware. Introduce the function ata_dev_config_lpm() to always disable DIPM on a device that supports this feature if the port of the device is flagged with ATA_FLAG_NO_DIPM. ata_dev_config_lpm() is called from ata_dev_configure(), ensuring that a device DIPM feature is disabled when it cannot be used. Signed-off-by: Damien Le Moal Reviewed-by: Niklas Cassel Reviewed-by: Hannes Reinecke Link: https://lore.kernel.org/r/20250701125321.69496-2-dlemoal@kernel.org Signed-off-by: Niklas Cassel Stable-dep-of: c8c6fb886f57 ("ata: libata: Print features also for ATAPI devices") Signed-off-by: Sasha Levin