6.16-stable review patch. If anyone has any objections, please let me know.
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From: Igor Pylypiv ipylypiv@google.com
commit 58768b0563916ddcb73d8ed26ede664915f8df31 upstream.
Delete extra checks for the ATA_DFLAG_CDL_ENABLED flag that prevent SET FEATURES command from being issued to a drive when NCQ commands are active.
ata_mselect_control_ata_feature() sets / clears the ATA_DFLAG_CDL_ENABLED flag during the translation of MODE SELECT to SET FEATURES. If SET FEATURES gets deferred due to outstanding NCQ commands, the original MODE SELECT command will be re-queued. When the re-queued MODE SELECT goes through the ata_mselect_control_ata_feature() translation again, SET FEATURES will not be issued because ATA_DFLAG_CDL_ENABLED has been already set or cleared by the initial translation of MODE SELECT.
The ATA_DFLAG_CDL_ENABLED checks in ata_mselect_control_ata_feature() are safe to remove because scsi_cdl_enable() implements a similar logic that avoids enabling CDL if it has been enabled already.
Fixes: 17e897a45675 ("ata: libata-scsi: Improve CDL control") Cc: stable@vger.kernel.org Signed-off-by: Igor Pylypiv ipylypiv@google.com Reviewed-by: Niklas Cassel cassel@kernel.org Signed-off-by: Damien Le Moal dlemoal@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/ata/libata-scsi.c | 11 +++-------- 1 file changed, 3 insertions(+), 8 deletions(-)
--- a/drivers/ata/libata-scsi.c +++ b/drivers/ata/libata-scsi.c @@ -3905,21 +3905,16 @@ static int ata_mselect_control_ata_featu /* Check cdl_ctrl */ switch (buf[0] & 0x03) { case 0: - /* Disable CDL if it is enabled */ - if (!(dev->flags & ATA_DFLAG_CDL_ENABLED)) - return 0; + /* Disable CDL */ ata_dev_dbg(dev, "Disabling CDL\n"); cdl_action = 0; dev->flags &= ~ATA_DFLAG_CDL_ENABLED; break; case 0x02: /* - * Enable CDL if not already enabled. Since this is mutually - * exclusive with NCQ priority, allow this only if NCQ priority - * is disabled. + * Enable CDL. Since CDL is mutually exclusive with NCQ + * priority, allow this only if NCQ priority is disabled. */ - if (dev->flags & ATA_DFLAG_CDL_ENABLED) - return 0; if (dev->flags & ATA_DFLAG_NCQ_PRIO_ENABLED) { ata_dev_err(dev, "NCQ priority must be disabled to enable CDL\n");