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Staging: zram: Fix kunmapping order

PATCH In review Jerome Marchand 2 participants 2 messages Jul 13, 2011 – Jul 14, 2011 Staging

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Jerome Marchand

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PATCH 1/1 Staging: zram: Fix kunmapping order

This patch fixes the unmapping order of KM_USER0/1 in handle_uncompressed_page() and zram_read() so that kmap()/kunmap() calls are correctly nested.

Reported-by Nitin Gupta <[email protected]>
Signed-off-by Jerome Marchand <[email protected]>
---
 zram_drv.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)
drivers/staging/zram/zram_drv.c +2 -2
index c5fdc55..d70ec1a 100644
@@ -199,8 +199,8 @@ static void handle_uncompressed_page(struct zram *zram, struct bio_vec *bvec,
 	cmem = kmap_atomic(zram->table[index].page, KM_USER1);
 
 	memcpy(user_mem + bvec->bv_offset, cmem + offset, bvec->bv_len);
-	kunmap_atomic(user_mem, KM_USER0);
 	kunmap_atomic(cmem, KM_USER1);
+	kunmap_atomic(user_mem, KM_USER0);
 
 	flush_dcache_page(page);
 }

@@ -267,8 +267,8 @@ static int zram_bvec_read(struct zram *zram, struct bio_vec *bvec,
 		kfree(uncmem);
 	}
 
-	kunmap_atomic(user_mem, KM_USER0);
 	kunmap_atomic(cmem, KM_USER1);
+	kunmap_atomic(user_mem, KM_USER0);
 
 	/* Should NEVER happen. Return bio error if it does. */
 	if (unlikely(ret != LZO_E_OK)) {