From: Jeff Dike <jdike@addtoit.com>
Date: Sun, 6 May 2007 21:51:44 +0000 (-0700)
Subject: uml: aIO deadlock avoidance
X-Git-Tag: v2.6.22-rc1~840
X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=8603ec81487a5fefbc29611ff0d635b33b6da990;p=linux-2.6

uml: aIO deadlock avoidance

Allow deadlocks to be avoided in the AIO code by setting the pipe to the I/O
thread non-blocking.

Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---

diff --git a/arch/um/os-Linux/aio.c b/arch/um/os-Linux/aio.c
index 5d258eb4f5..9bf944f6a1 100644
--- a/arch/um/os-Linux/aio.c
+++ b/arch/um/os-Linux/aio.c
@@ -221,6 +221,11 @@ static int init_aio_24(void)
 
 	aio_req_fd_w = fds[0];
 	aio_req_fd_r = fds[1];
+
+	err = os_set_fd_block(aio_req_fd_w, 0);
+	if(err)
+		goto out_close_pipe;
+
 	err = run_helper_thread(not_aio_thread, NULL,
 				CLONE_FILES | CLONE_VM | SIGCHLD, &stack, 0);
 	if(err < 0)