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 6e98af7b74db2705eef9d362914041d961146e2c..a012e7e935ad48b44f0ae4b6991c24b7e807a6d6 100644 (file)
--- 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);