From 85d492f28d056c40629fc25d79f54da618a29dc4 Mon Sep 17 00:00:00 2001 From: Minchan Kim Date: Thu, 13 Apr 2017 14:56:40 -0700 Subject: [PATCH] zsmalloc: expand class bit Now 64K page system, zsamlloc has 257 classes so 8 class bit is not enough. With that, it corrupts the system when zsmalloc stores 65536byte data(ie, index number 256) so that this patch increases class bit for simple fix for stable backport. We should clean up this mess soon. index size 0 32 1 288 .. .. 204 52256 256 65536 Fixes: 3783689a1 ("zsmalloc: introduce zspage structure") Link: http://lkml.kernel.org/r/1492042622-12074-3-git-send-email-minchan@kernel.org Signed-off-by: Minchan Kim Cc: Sergey Senozhatsky Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/zsmalloc.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/mm/zsmalloc.c b/mm/zsmalloc.c index b7ee9c34dbd6..d41edd28298b 100644 --- a/mm/zsmalloc.c +++ b/mm/zsmalloc.c @@ -276,7 +276,7 @@ struct zs_pool { struct zspage { struct { unsigned int fullness:FULLNESS_BITS; - unsigned int class:CLASS_BITS; + unsigned int class:CLASS_BITS + 1; unsigned int isolated:ISOLATED_BITS; unsigned int magic:MAGIC_VAL_BITS; };