4.9-stable review patch. If anyone has any objections, please let me know.
------------------ From: Minchan Kim <[email protected]> commit e7ccfc4ccb703e0f033bd4617580039898e912dd upstream. Commit b4c5c60920e3 ("zram: avoid lockdep splat by revalidate_disk") moved revalidate_disk call out of init_lock to avoid lockdep false-positive splat. However, commit 08eee69fcf6b ("zram: remove init_lock in zram_make_request") removed init_lock in IO path so there is no worry about lockdep splat. So, let's restore it. This patch is needed to set BDI_CAP_STABLE_WRITES atomically in next patch. Fixes: da9556a2367c ("zram: user per-cpu compression streams") Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Minchan Kim <[email protected]> Reviewed-by: Sergey Senozhatsky <[email protected]> Cc: Takashi Iwai <[email protected]> Cc: Hyeoncheol Lee <[email protected]> Cc: <[email protected]> Cc: Sangseok Lee <[email protected]> Cc: Hugh Dickins <[email protected]> Cc: Darrick J. Wong <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- drivers/block/zram/zram_drv.c | 8 +------- 1 file changed, 1 insertion(+), 7 deletions(-) --- a/drivers/block/zram/zram_drv.c +++ b/drivers/block/zram/zram_drv.c @@ -1094,14 +1094,8 @@ static ssize_t disksize_store(struct dev zram->comp = comp; zram->disksize = disksize; set_capacity(zram->disk, zram->disksize >> SECTOR_SHIFT); - up_write(&zram->init_lock); - - /* - * Revalidate disk out of the init_lock to avoid lockdep splat. - * It's okay because disk's capacity is protected by init_lock - * so that revalidate_disk always sees up-to-date capacity. - */ revalidate_disk(zram->disk); + up_write(&zram->init_lock); return len;
