So, we got no reponse from the MM maintainers. Marek - please try this
patch on all the machines where you hit the bug and if you still hit the
bug with this patch, report it.
Mikulas
From: Mikulas Patocka <mpatocka@xxxxxxxxxx>
Subject: [PATCH] dm-crypt: don't allocate large compound pages
It was reported that the patch 5054e778fcd9cd29ddaa8109077cd235527e4f94
("dm crypt: allocate compound pages if possible") causes intermittent
freezes [1].
So far, it is not clear what is the root cause. It was reported that with
the allocation order 3 or lower it works [1], so we restrict the order to
3 (that is PAGE_ALLOC_COSTLY_ORDER).
[1] https://www.spinics.net/lists/dm-devel/msg56048.html
Signed-off-by: Mikulas Patocka <mpatocka@xxxxxxxxxx>
Reported-by: Marek Marczykowski-Górecki <marmarek@xxxxxxxxxxxxxxxxxxxxxx>
Tested-by: Marek Marczykowski-Górecki <marmarek@xxxxxxxxxxxxxxxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx # v6.5+
Fixes: 5054e778fcd9 ("dm crypt: allocate compound pages if possible")
---
drivers/md/dm-crypt.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
Index: linux-2.6/drivers/md/dm-crypt.c
===================================================================
--- linux-2.6.orig/drivers/md/dm-crypt.c
+++ linux-2.6/drivers/md/dm-crypt.c
@@ -1679,7 +1679,7 @@ static struct bio *crypt_alloc_buffer(st
unsigned int nr_iovecs = (size + PAGE_SIZE - 1) >> PAGE_SHIFT;
gfp_t gfp_mask = GFP_NOWAIT | __GFP_HIGHMEM;
unsigned int remaining_size;
- unsigned int order = MAX_ORDER - 1;
+ unsigned int order = PAGE_ALLOC_COSTLY_ORDER;
retry:
if (unlikely(gfp_mask & __GFP_DIRECT_RECLAIM))
