There is a race condition as below when calling request_firmware():
CPU1 CPU2
write 0 > loading
mutex_lock(&fw_lock);
...
set_bit FW_STATUS_DONE class_timeout is coming
set_bit FW_STATUS_ABORT
complete_all &completion
...
mutex_unlock(&fw_lock)
In this time, the bit FW_STATUS_DONE and FW_STATUS_ABORT are set,
and request_firmware() will return failure due to condition in
_request_firmware_load():
if (!buf->size || test_bit(FW_STATUS_ABORT, &buf->status))
retval = -ENOENT;
But from the above scenerio, it should be a succcessful requesting.
So we need judge if the FW_STATUS_DONE is set before calling abort
in timeout function firmware_class_timeout().
Signed-off-by: liu chuansheng <[email protected]>
---
drivers/base/firmware_class.c | 7 +++++++
1 files changed, 7 insertions(+), 0 deletions(-)
diff --git a/drivers/base/firmware_class.c b/drivers/base/firmware_class.c
index 8945f4e..35fffd8 100644
--- a/drivers/base/firmware_class.c
+++ b/drivers/base/firmware_class.c
@@ -671,6 +671,13 @@ static void firmware_class_timeout(u_long data)
{
struct firmware_priv *fw_priv = (struct firmware_priv *) data;
+ mutex_lock(&fw_lock);
+ if (test_bit(FW_STATUS_DONE, &(fw_priv->buf->status))) {
+ mutex_unlock(&fw_lock);
+ return;
+ }
+ mutex_unlock(&fw_lock);
+
fw_load_abort(fw_priv);
}
--
1.7.0.4
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
