The patch titled Subject: zram: avoid kunmap_atomic() of a NULL pointer has been removed from the -mm tree. Its filename was zram-avoid-kunmap_atomic-a-null-pointer.patch This patch was dropped because it was merged into mainline or a subsystem tree ------------------------------------------------------ From: Weijie Yang <weijie.yang@xxxxxxxxxxx> Subject: zram: avoid kunmap_atomic() of a NULL pointer zram could kunmap_atomic() a NULL pointer in a rare situation: a zram page becomes a full-zeroed page after a partial write io. The current code doesn't handle this case and performs kunmap_atomic() on a NULL pointer, which panics the kernel. This patch fixes this issue. Signed-off-by: Weijie Yang <weijie.yang@xxxxxxxxxxx> Cc: Sergey Senozhatsky <sergey.senozhatsky@xxxxxxxxx> Cc: Dan Streetman <ddstreet@xxxxxxxx> Cc: Nitin Gupta <ngupta@xxxxxxxxxx> Cc: Weijie Yang <weijie.yang.kh@xxxxxxxxx> Acked-by: Jerome Marchand <jmarchan@xxxxxxxxxx> Cc: <stable@xxxxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- drivers/block/zram/zram_drv.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff -puN drivers/block/zram/zram_drv.c~zram-avoid-kunmap_atomic-a-null-pointer drivers/block/zram/zram_drv.c --- a/drivers/block/zram/zram_drv.c~zram-avoid-kunmap_atomic-a-null-pointer +++ a/drivers/block/zram/zram_drv.c @@ -560,7 +560,8 @@ static int zram_bvec_write(struct zram * } if (page_zero_filled(uncmem)) { - kunmap_atomic(user_mem); + if (user_mem) + kunmap_atomic(user_mem); /* Free memory associated with this sector now. */ bit_spin_lock(ZRAM_ACCESS, &meta->table[index].value); zram_free_page(zram, index); _ Patches currently in -mm which might be from weijie.yang@xxxxxxxxxxx are mm-page_isolation-check-pfn-validity-before-access.patch mm-mincore-add-hwpoison-page-handle.patch mm-mincore-add-hwpoison-page-handle-checkpatch-fixes.patch -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html