queue-6.1/ata-libata-sata-disallow-changing-lpm-state-if-not-s.patch

From 14d03024780d92ce0e9c3c7ed6011e44d4f40ec3 Mon Sep 17 00:00:00 2001
From: Sasha Levin <sashal@kernel.org>
Date: Tue, 1 Jul 2025 21:53:16 +0900
Subject: ata: libata-sata: Disallow changing LPM state if not supported

From: Damien Le Moal <dlemoal@kernel.org>

[ Upstream commit 413e800cadbf67550d76c77c230b2ecd96bce83a ]

Modify ata_scsi_lpm_store() to return an error if a user attempts to set
a link power management policy for a port that does not support LPM,
that is, ports flagged with ATA_FLAG_NO_LPM.

Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Niklas Cassel <cassel@kernel.org>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Link: https://lore.kernel.org/r/20250701125321.69496-6-dlemoal@kernel.org
Signed-off-by: Niklas Cassel <cassel@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/ata/libata-sata.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/ata/libata-sata.c b/drivers/ata/libata-sata.c
index 71a00842eb5e..b75999388bf0 100644
--- a/drivers/ata/libata-sata.c
+++ b/drivers/ata/libata-sata.c
@@ -812,6 +812,11 @@ static ssize_t ata_scsi_lpm_store(struct device *device,
 
 	spin_lock_irqsave(ap->lock, flags);
 
+	if (ap->flags & ATA_FLAG_NO_LPM) {
+		count = -EOPNOTSUPP;
+		goto out_unlock;
+	}
+
 	ata_for_each_link(link, ap, EDGE) {
 		ata_for_each_dev(dev, &ap->link, ENABLED) {
 			if (dev->horkage & ATA_HORKAGE_NOLPM) {
-- 
2.39.5