Make sure that backends array has anything apart from the sentinel NULL value. We also select LZO_BACKEND if none backends were selected. Signed-off-by: Sergey Senozhatsky <senozhatsky@xxxxxxxxxxxx> --- drivers/block/zram/Kconfig | 19 +++++++++++++------ drivers/block/zram/zcomp.c | 8 ++++++++ 2 files changed, 21 insertions(+), 6 deletions(-) diff --git a/drivers/block/zram/Kconfig b/drivers/block/zram/Kconfig index 1e0e7e5910b8..6aea609b795c 100644 --- a/drivers/block/zram/Kconfig +++ b/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 diff --git a/drivers/block/zram/zcomp.c b/drivers/block/zram/zcomp.c index 2a38126f4da3..d49791f724e9 100644 --- a/drivers/block/zram/zcomp.c +++ b/drivers/block/zram/zcomp.c @@ -209,6 +209,14 @@ struct zcomp *zcomp_create(const char *alg) 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); -- 2.45.0.rc1.225.g2a3ae87e7f-goog
