Commit 8130b9d5 authored Mar 03, 2020 by Dongli Zhang Committed by Boris Ostrovsky Mar 05, 2020

xenbus: req->err should be updated before req->state



This patch adds the barrier to guarantee that req->err is always updated
before req->state.

Otherwise, read_reply() would not return ERR_PTR(req->err) but
req->body, when process_writes()->xb_write() is failed.

Signed-off-by: Dongli Zhang <dongli.zhang@oracle.com>
Link: https://lore.kernel.org/r/20200303221423.21962-2-dongli.zhang@oracle.com


Reviewed-by: Julien Grall <jgrall@amazon.com>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>

parent 1b6a51e8

drivers/xen/xenbus/xenbus_comms.c

+2 −0

Original line number	Diff line number	Diff line
		@@ -397,6 +397,8 @@ static int process_writes(void)
		if (state.req->state == xb_req_state_aborted)
		kfree(state.req);
		else {
		/* write err, then update state */
		virt_wmb();
		state.req->state = xb_req_state_got_reply;
		wake_up(&state.req->wq);
		}

Admin message