[PATCH AUTOSEL 6.6 70/83] phy: zynqmp: Take the phy mutex in xlate

Sasha Levin
2024-08-01T00:25:48Z

From: Sean Anderson <sean.anderson@linux.dev>

[ Upstream commit d79c6840917097285e03a49f709321f5fb972750 ]

Take the phy mutex in xlate to protect against concurrent
modification/access to gtr_phy. This does not typically cause any
issues, since in most systems the phys are only xlated once and
thereafter accessed with the phy API (which takes the locks). However,
we are about to allow userspace to access phys for debugging, so it's
important to avoid any data races.

Signed-off-by: Sean Anderson <sean.anderson@linux.dev>
Link: https://lore.kernel.org/r/20240628205540.3098010-5-sean.anderson@linux.dev
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/phy/xilinx/phy-zynqmp.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/drivers/phy/xilinx/phy-zynqmp.c b/drivers/phy/xilinx/phy-zynqmp.c
index 2559c6594cea2..b2b761e8d6a3a 100644
--- a/drivers/phy/xilinx/phy-zynqmp.c
+++ b/drivers/phy/xilinx/phy-zynqmp.c
@@ -798,6 +798,7 @@ static struct phy *xpsgtr_xlate(struct device *dev,
phy_type = args->args[1];
phy_instance = args->args[2];

+ guard(mutex)(&gtr_phy->phy->mutex);
ret = xpsgtr_set_lane_type(gtr_phy, phy_type, phy_instance);
if (ret < 0) {
dev_err(gtr_dev->dev, "Invalid PHY type and/or instance\n");
--
2.43.0