On 2021/8/19 23:55, David Teigland wrote:
On Thu, Aug 19, 2021 at 04:54:57PM +0800, Jia-Ju Bai wrote:
Hello,
My static analysis tool reports a possible ABBA deadlock in the dlm
filesystem in Linux 5.10:
dlm_recover_waiters_pre()
mutex_lock(&ls->ls_waiters_mutex); --> line 5130
recover_convert_waiter()
_receive_convert_reply()
lock_rsb()
mutex_lock(&r->res_mutex); --> line 69
dlm_recover_waiters_post()
lock_rsb()
mutex_lock(&r->res_mutex); --> line 69
mutex_lock(&ls->ls_waiters_mutex); --> line 5307
When dlm_recover_waiters_pre() and dlm_recover_waiters_post() are
concurrently executed, the deadlock can occur.
I am not quite sure whether this possible deadlock is real and how to fix it
if it is real.
Any feedback would be appreciated, thanks :)
They won't be concurrent, "pre" runs before recovery, and "post" is after.
Okay, thanks for your reply :)
Best wishes,
Jia-Ju Bai
