The following expression is incorrect because blk_pread_nonzeroes()
deals in units of bytes, not sectors:

  bytes = MIN(size - offset, BDRV_REQUEST_MAX_SECTORS)
                                              ^^^^^^^

BDRV_REQUEST_MAX_BYTES is the appropriate constant.

Fixes: a4b15a8b9ef2 ("pflash: Only read non-zero parts of backend image")
Cc: Xiang Zheng <zhengxia...@huawei.com>
Signed-off-by: Stefan Hajnoczi <stefa...@redhat.com>
---
 hw/block/block.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/hw/block/block.c b/hw/block/block.c
index 9f52ee6e72..ff503002aa 100644
--- a/hw/block/block.c
+++ b/hw/block/block.c
@@ -30,7 +30,7 @@ static int blk_pread_nonzeroes(BlockBackend *blk, hwaddr 
size, void *buf)
     BlockDriverState *bs = blk_bs(blk);
 
     for (;;) {
-        bytes = MIN(size - offset, BDRV_REQUEST_MAX_SECTORS);
+        bytes = MIN(size - offset, BDRV_REQUEST_MAX_BYTES);
         if (bytes <= 0) {
             return 0;
         }
-- 
2.43.0


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