+ kasan-remove-the-unnecessary-warn_once-from-quarantinec.patch added to -mm tree

+ kasan-remove-the-unnecessary-warn_once-from-quarantinec.patch added to -mm tree

[akpm]

The patch titled
     Subject: kasan: remove the unnecessary WARN_ONCE from quarantine.c
has been added to the -mm tree.  Its filename is
     kasan-remove-the-unnecessary-warn_once-from-quarantinec.patch

This patch should soon appear at
    http://ozlabs.org/~akpm/mmots/broken-out/kasan-remove-the-unnecessary-warn_once-from-quarantinec.patch
and later at
    http://ozlabs.org/~akpm/mmotm/broken-out/kasan-remove-the-unnecessary-warn_once-from-quarantinec.patch

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------------------------------------------------------
From: Alexander Potapenko <glider@google.com>
Subject: kasan: remove the unnecessary WARN_ONCE from quarantine.c

It's quite unlikely that the user will so little memory that the
per-CPU quarantines won't fit into the given fraction of the available
memory. Even in that case he won't be able to do anything with the
information given in the warning.

Link: http://lkml.kernel.org/r/1470929182-101413-1-git-send-email-glider@google.com
Signed-off-by: Alexander Potapenko <glider@google.com>
Acked-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Andrey Konovalov <adech.fo@gmail.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Kuthonuzo Luruo <kuthonuzo.luruo@hpe.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/kasan/quarantine.c |    7 ++-----
 1 file changed, 2 insertions(+), 5 deletions(-)

diff -puN mm/kasan/quarantine.c~kasan-remove-the-unnecessary-warn_once-from-quarantinec mm/kasan/quarantine.c
--- a/mm/kasan/quarantine.c~kasan-remove-the-unnecessary-warn_once-from-quarantinec
+++ a/mm/kasan/quarantine.c
@@ -217,11 +217,8 @@ void quarantine_reduce(void)
 	new_quarantine_size = (READ_ONCE(totalram_pages) << PAGE_SHIFT) /
 		QUARANTINE_FRACTION;
 	percpu_quarantines = QUARANTINE_PERCPU_SIZE * num_online_cpus();
-	if (WARN_ONCE(new_quarantine_size < percpu_quarantines,
-		"Too little memory, disabling global KASAN quarantine.\n"))
-		new_quarantine_size = 0;
-	else
-		new_quarantine_size -= percpu_quarantines;
+	new_quarantine_size = (new_quarantine_size < percpu_quarantines) ?
+		0 : new_quarantine_size - percpu_quarantines;
 	WRITE_ONCE(quarantine_size, new_quarantine_size);
 
 	last = global_quarantine.head;
_

Patches currently in -mm which might be from glider@google.com are

kasan-remove-the-unnecessary-warn_once-from-quarantinec.patch