We don't need to call zram_meta_free, zcomp_destroy and zs_free
under init_lock. What we need to prevent race with init_lock
in reset is setting NULL into zram->meta (ie, init_done).
This patch does it.

Signed-off-by: Minchan Kim <minc...@kernel.org>
---
 drivers/block/zram/zram_drv.c | 28 ++++++++++++++++------------
 1 file changed, 16 insertions(+), 12 deletions(-)

diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c
index 9250b3f54a8f..0299d82275e7 100644
--- a/drivers/block/zram/zram_drv.c
+++ b/drivers/block/zram/zram_drv.c
@@ -708,6 +708,7 @@ static void zram_reset_device(struct zram *zram, bool 
reset_capacity)
 {
        size_t index;
        struct zram_meta *meta;
+       struct zcomp *comp;
 
        down_write(&zram->init_lock);
 
@@ -719,20 +720,10 @@ static void zram_reset_device(struct zram *zram, bool 
reset_capacity)
        }
 
        meta = zram->meta;
-       /* Free all pages that are still in this zram device */
-       for (index = 0; index < zram->disksize >> PAGE_SHIFT; index++) {
-               unsigned long handle = meta->table[index].handle;
-               if (!handle)
-                       continue;
-
-               zs_free(meta->mem_pool, handle);
-       }
-
-       zcomp_destroy(zram->comp);
+       comp = zram->comp;
+       zram->meta = NULL;
        zram->max_comp_streams = 1;
 
-       zram_meta_free(zram->meta);
-       zram->meta = NULL;
        /* Reset stats */
        memset(&zram->stats, 0, sizeof(zram->stats));
 
@@ -742,6 +733,19 @@ static void zram_reset_device(struct zram *zram, bool 
reset_capacity)
 
        up_write(&zram->init_lock);
 
+       /* Free all pages that are still in this zram device */
+       for (index = 0; index < zram->disksize >> PAGE_SHIFT; index++) {
+               unsigned long handle = meta->table[index].handle;
+
+               if (!handle)
+                       continue;
+
+               zs_free(meta->mem_pool, handle);
+       }
+
+       zcomp_destroy(comp);
+       zram_meta_free(meta);
+
        /*
         * Revalidate disk out of the init_lock to avoid lockdep splat.
         * It's okay because disk's capacity is protected by init_lock
-- 
1.9.1

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