From: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Date: Tue, 23 Mar 2010 20:35:30 +0000 (-0700)
Subject: tmpfs: mpol=bind:0 don't cause mount error.
X-Git-Tag: firefly_0821_release~10186^2~1979
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=55bb6ea6c037942d111e812f0b212f3d9065a735;p=firefly-linux-kernel-4.4.55.git

tmpfs: mpol=bind:0 don't cause mount error.

commit d69b2e63e9172afb4d07c305601b79a55509ac4c upstream.

Currently, following mount operation cause mount error.

% mount -t tmpfs -ompol=bind:0 none /tmp

Because commit 71fe804b6d5 (mempolicy: use struct mempolicy pointer in
shmem_sb_info) corrupted MPOL_BIND parse code.

This patch restore the needed one.

Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Ravikiran Thirumalai <kiran@scalex86.org>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: Mel Gorman <mel@csn.ul.ie>
Acked-by: Lee Schermerhorn <lee.schermerhorn@hp.com>
Cc: Hugh Dickins <hugh.dickins@tiscali.co.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
---

diff --git a/mm/mempolicy.c b/mm/mempolicy.c
index 13855e22aada..b2f22557b8ff 100644
--- a/mm/mempolicy.c
+++ b/mm/mempolicy.c
@@ -2149,9 +2149,13 @@ int mpol_parse_str(char *str, struct mempolicy **mpol, int no_context)
 		if (!nodelist)
 			err = 0;
 		goto out;
-	/*
-	 * case MPOL_BIND:    mpol_new() enforces non-empty nodemask.
-	 */
+	case MPOL_BIND:
+		/*
+		 * Insist on a nodelist
+		 */
+		if (!nodelist)
+			goto out;
+		err = 0;
 	}
 
 	mode_flags = 0;