[PATCH 6.8 551/715] platform/x86/amd/pmf: Do not use readl() for policy buffer access

From: Sasha Levin
Date: Sun Mar 24 2024 - 20:37:50 EST


From: Armin Wolf <W_Armin@xxxxxx>

[ Upstream commit e42dddce83a0578a518cb7078930c8269a6083af ]

The policy buffer is allocated using normal memory allocation
functions, so readl() should not be used on it.

Compile-tested only.

Fixes: 7c45534afa44 ("platform/x86/amd/pmf: Add support for PMF Policy Binary")
Signed-off-by: Armin Wolf <W_Armin@xxxxxx>
Reviewed-by: Shyam Sundar S K <Shyam-sundar.S-k@xxxxxxx>
Link: https://lore.kernel.org/r/20240304205005.10078-3-W_Armin@xxxxxx
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@xxxxxxxxxxxxxxx>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@xxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/platform/x86/amd/pmf/tee-if.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/platform/x86/amd/pmf/tee-if.c b/drivers/platform/x86/amd/pmf/tee-if.c
index dcbe8f85e1229..4ebfe0f5a7fb2 100644
--- a/drivers/platform/x86/amd/pmf/tee-if.c
+++ b/drivers/platform/x86/amd/pmf/tee-if.c
@@ -249,8 +249,8 @@ static int amd_pmf_start_policy_engine(struct amd_pmf_dev *dev)
u32 cookie, length;
int res;

- cookie = readl(dev->policy_buf + POLICY_COOKIE_OFFSET);
- length = readl(dev->policy_buf + POLICY_COOKIE_LEN);
+ cookie = *(u32 *)(dev->policy_buf + POLICY_COOKIE_OFFSET);
+ length = *(u32 *)(dev->policy_buf + POLICY_COOKIE_LEN);

if (cookie != POLICY_SIGN_COOKIE || !length) {
dev_dbg(dev->dev, "cookie doesn't match\n");
--
2.43.0