From: Dominique Martinet <dominique.martinet@xxxxxxxxxxxxxxxxx> This is a pre-requisite for the backport of commit 74363ec674cb ("zram: fix uninitialized ZRAM not releasing backing device"), which has been implemented differently in commit 7ac07a26dea7 ("zram: preparation for multi-zcomp support") upstream. We only need to ensure that zcomp_destroy is not called with a NULL comp, so add this check as the other commit cannot be backported easily. Stable-dep-of: 74363ec674cb ("zram: fix uninitialized ZRAM not releasing backing device") Link: https://lore.kernel.org/Z3ytcILx4S1v_ueJ@xxxxxxxxxxxxx Suggested-by: Kairui Song <kasong@xxxxxxxxxxx> Signed-off-by: Dominique Martinet <dominique.martinet@xxxxxxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/block/zram/zram_drv.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/drivers/block/zram/zram_drv.c +++ b/drivers/block/zram/zram_drv.c @@ -1733,7 +1733,8 @@ static void zram_reset_device(struct zra zram_meta_free(zram, zram->disksize); zram->disksize = 0; memset(&zram->stats, 0, sizeof(zram->stats)); - zcomp_destroy(zram->comp); + if (zram->comp) + zcomp_destroy(zram->comp); zram->comp = NULL; reset_bdev(zram); Patches currently in stable-queue which might be from dominique.martinet@xxxxxxxxxxxxxxxxx are queue-6.1/zram-check-comp-is-non-null-before-calling-comp_destroy.patch