The quilt patch titled
Subject: zram: check that backends array has at least one backend
has been removed from the -mm tree. Its filename was
zram-check-that-backends-array-has-at-least-one-backend.patch
This patch was dropped because it was merged into the mm-stable branch
of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
------------------------------------------------------
From: Sergey Senozhatsky <senozhatsky@xxxxxxxxxxxx>
Subject: zram: check that backends array has at least one backend
Date: Mon, 2 Sep 2024 19:56:00 +0900
Make sure that backends array has anything apart from the sentinel NULL
value.
We also select LZO_BACKEND if none backends were selected.
Link: https://lkml.kernel.org/r/20240902105656.1383858-13-senozhatsky@xxxxxxxxxxxx
Signed-off-by: Sergey Senozhatsky <senozhatsky@xxxxxxxxxxxx>
Cc: Minchan Kim <minchan@xxxxxxxxxx>
Cc: Nick Terrell <terrelln@xxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
drivers/block/zram/Kconfig | 19 +++++++++++++------
drivers/block/zram/zcomp.c | 8 ++++++++
2 files changed, 21 insertions(+), 6 deletions(-)
--- a/drivers/block/zram/Kconfig~zram-check-that-backends-array-has-at-least-one-backend
+++ a/drivers/block/zram/Kconfig
@@ -14,12 +14,6 @@ config ZRAM
See Documentation/admin-guide/blockdev/zram.rst for more information.
-config ZRAM_BACKEND_LZO
- bool "lzo and lzo-rle compression support"
- depends on ZRAM
- select LZO_COMPRESS
- select LZO_DECOMPRESS
-
config ZRAM_BACKEND_LZ4
bool "lz4 compression support"
depends on ZRAM
@@ -50,6 +44,19 @@ config ZRAM_BACKEND_842
select 842_COMPRESS
select 842_DECOMPRESS
+config ZRAM_BACKEND_FORCE_LZO
+ depends on ZRAM
+ def_bool !ZRAM_BACKEND_LZ4 && !ZRAM_BACKEND_LZ4HC && \
+ !ZRAM_BACKEND_ZSTD && !ZRAM_BACKEND_DEFLATE && \
+ !ZRAM_BACKEND_842
+
+config ZRAM_BACKEND_LZO
+ bool "lzo and lzo-rle compression support" if !ZRAM_BACKEND_FORCE_LZO
+ depends on ZRAM
+ default ZRAM_BACKEND_FORCE_LZO
+ select LZO_COMPRESS
+ select LZO_DECOMPRESS
+
choice
prompt "Default zram compressor"
default ZRAM_DEF_COMP_LZORLE
--- a/drivers/block/zram/zcomp.c~zram-check-that-backends-array-has-at-least-one-backend
+++ a/drivers/block/zram/zcomp.c
@@ -192,6 +192,14 @@ struct zcomp *zcomp_create(const char *a
struct zcomp *comp;
int error;
+ /*
+ * The backends array has a sentinel NULL value, so the minimum
+ * size is 1. In order to be valid the array, apart from the
+ * sentinel NULL element, should have at least one compression
+ * backend selected.
+ */
+ BUILD_BUG_ON(ARRAY_SIZE(backends) <= 1);
+
comp = kzalloc(sizeof(struct zcomp), GFP_KERNEL);
if (!comp)
return ERR_PTR(-ENOMEM);
_
Patches currently in -mm which might be from senozhatsky@xxxxxxxxxxxx are
zsmalloc-use-unique-zsmalloc-caches-names.patch
