From: Stefan Hajnoczi <stefanha@redhat.com>
Date: Tue, 30 Jan 2024 00:27:12 +0000 (-0500)
Subject: pflash: fix sectors vs bytes confusion in blk_pread_nonzeroes()
X-Git-Tag: v9.0.0~131^2~2
X-Git-Url: https://git.proxmox.com/?a=commitdiff_plain;h=d5eaeefbdac30d9ca62612f18e2d3f4509272856;hp=615eaeab3d318ba239d54141a4251746782f65c1;p=mirror_qemu.git

pflash: fix sectors vs bytes confusion in blk_pread_nonzeroes()

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 <zhengxiang9@huawei.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-id: 20240130002712.257815-1-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
---

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;
         }