From: Lizhi Hou <lizhi.hou@amd.com>
Date: Thu, 7 May 2026 04:02:07 +0000 (-0700)
Subject: accel/amdxdna: Fix clflush buffer size
X-Git-Url: http://git.ipfire.org/gitweb/index.cgi?a=commitdiff_plain;h=ada61841caede131cc626f6cd28a60904296f248;p=thirdparty%2Fkernel%2Flinux.git

accel/amdxdna: Fix clflush buffer size

The firmware is told the buffer is req.buf_size bytes. It may read/write
the entire region. If the CPU only flushes a subset, the remaining cache
lines could contain stale data, causing the device to see garbage.

Fixes: 6e87001fe19f ("accel/amdxdna: Adjust size for copy_to_user()")
Reviewed-by: Mario Limonciello (AMD) <superm1@kernel.org>
Signed-off-by: Lizhi Hou <lizhi.hou@amd.com>
Link: https://patch.msgid.link/20260507040207.178111-1-lizhi.hou@amd.com
---

diff --git a/drivers/accel/amdxdna/aie2_message.c b/drivers/accel/amdxdna/aie2_message.c
index 6e98af7b74db..a012e7e935ad 100644
--- a/drivers/accel/amdxdna/aie2_message.c
+++ b/drivers/accel/amdxdna/aie2_message.c
@@ -390,7 +390,7 @@ int aie2_query_status(struct amdxdna_dev_hdl *ndev, char __user *buf,
 	req.num_cols = hweight32(aie_bitmap);
 	req.aie_bitmap = aie_bitmap;
 
-	drm_clflush_virt_range(buff_addr, size); /* device can access */
+	drm_clflush_virt_range(buff_addr, req.dump_buff_size); /* device can access */
 	ret = aie_send_mgmt_msg_wait(&ndev->aie, &msg);
 	if (ret) {
 		XDNA_ERR(xdna, "Error during NPU query, status %d", ret);
@@ -442,7 +442,7 @@ int aie2_query_telemetry(struct amdxdna_dev_hdl *ndev,
 	req.buf_size = buf_sz;
 	req.type = header->type;
 
-	drm_clflush_virt_range(addr, size); /* device can access */
+	drm_clflush_virt_range(addr, req.buf_size); /* device can access */
 	ret = aie_send_mgmt_msg_wait(&ndev->aie, &msg);
 	if (ret) {
 		XDNA_ERR(xdna, "Query telemetry failed, status %d", ret);
@@ -1186,7 +1186,7 @@ int aie2_query_app_health(struct amdxdna_dev_hdl *ndev, u32 context_id,
 	req.context_id = context_id;
 	req.buf_size = buf_size;
 
-	drm_clflush_virt_range(buf, sizeof(*report));
+	drm_clflush_virt_range(buf, req.buf_size);
 	ret = aie_send_mgmt_msg_wait(&ndev->aie, &msg);
 	if (ret) {
 		XDNA_ERR(xdna, "Get app health failed, ret %d status 0x%x", ret, resp.status);