4.10-stable review patch. If anyone has any objections, please let me know.
------------------ From: Minchan Kim <[email protected]> commit 85d492f28d056c40629fc25d79f54da618a29dc4 upstream. 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/[email protected] Signed-off-by: Minchan Kim <[email protected]> Cc: Sergey Senozhatsky <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- mm/zsmalloc.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/mm/zsmalloc.c +++ b/mm/zsmalloc.c @@ -280,7 +280,7 @@ 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; };
