diff options
| author | Damien Le Moal <dlemoal@kernel.org> | 2025-07-01 21:53:19 +0900 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2025-08-20 18:30:20 +0200 |
| commit | aa078896e33125708b1a9ed947be96570937a862 (patch) | |
| tree | 380163ba635b8835eac0220af25f0d055ec9a0ba | |
| parent | afa5ceab9d234ba8db805024fd8009b368d5a90d (diff) | |
ata: ahci: Disallow LPM policy control if not supported
[ Upstream commit 65b2c92f69d3df81422d27e5be012e357e733241 ]
Commit fa997b0576c9 ("ata: ahci: Do not enable LPM if no LPM states are
supported by the HBA") introduced an early return in
ahci_update_initial_lpm_policy() to ensure that the target_lpm_policy
of ports belonging to a host that does not support the Partial, Slumber
and DevSleep power states is unchanged and remains set to
ATA_LPM_UNKNOWN and thus prevents the execution of
ata_eh_link_set_lpm().
However, a user or a system daemon (e.g. systemd-udevd) may still
attempt changing the LPM policy through the sysfs
link_power_management_policy of the host.
Improve this to prevent sysfs LPM policy changes by setting the flag
ATA_FLAG_NO_LPM for the port of such host, and initialize the port
target_lpm_policy to ATA_LPM_MAX_POWER to guarantee that no unsupported
low power state is being used on the port and its link.
Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Niklas Cassel <cassel@kernel.org>
Link: https://lore.kernel.org/r/20250701125321.69496-9-dlemoal@kernel.org
Signed-off-by: Niklas Cassel <cassel@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
| -rw-r--r-- | drivers/ata/ahci.c | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/drivers/ata/ahci.c b/drivers/ata/ahci.c index a6a66d794763..61d34ca0d9f4 100644 --- a/drivers/ata/ahci.c +++ b/drivers/ata/ahci.c @@ -1785,7 +1785,10 @@ static void ahci_update_initial_lpm_policy(struct ata_port *ap) if ((ap->host->flags & ATA_HOST_NO_PART) && (ap->host->flags & ATA_HOST_NO_SSC) && (ap->host->flags & ATA_HOST_NO_DEVSLP)) { - ata_port_dbg(ap, "no LPM states supported, not enabling LPM\n"); + ata_port_dbg(ap, + "No LPM states supported, forcing LPM max_power\n"); + ap->flags |= ATA_FLAG_NO_LPM; + ap->target_lpm_policy = ATA_LPM_MAX_POWER; return; } |