Patchwork [v2] Avoid divide by zero when there is no block device to migrate

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Submitter Pierre Riteau
Date Jan. 12, 2011, 1:41 p.m.
Message ID <1294839660-3918-1-git-send-email-Pierre.Riteau@irisa.fr>
Download mbox | patch
Permalink /patch/78576/
State New
Headers show

Comments

Pierre Riteau - Jan. 12, 2011, 1:41 p.m.
When block migration is requested and no read-write block device is
present, a divide by zero exception is triggered because
total_sector_sum equals zero.

Signed-off-by: Pierre Riteau <Pierre.Riteau@irisa.fr>
---
 This v2 fixes a line that was going beyond 80 characters.

 block-migration.c |    7 ++++++-
 1 files changed, 6 insertions(+), 1 deletions(-)
Kevin Wolf - Jan. 13, 2011, 9:01 a.m.
Am 12.01.2011 14:41, schrieb Pierre Riteau:
> When block migration is requested and no read-write block device is
> present, a divide by zero exception is triggered because
> total_sector_sum equals zero.
> 
> Signed-off-by: Pierre Riteau <Pierre.Riteau@irisa.fr>
> ---
>  This v2 fixes a line that was going beyond 80 characters.

Thanks, applied to the block branch.

Kevin

Patch

diff --git a/block-migration.c b/block-migration.c
index 1475325..60b9fc0 100644
--- a/block-migration.c
+++ b/block-migration.c
@@ -350,7 +350,12 @@  static int blk_mig_save_bulked_block(Monitor *mon, QEMUFile *f)
         }
     }
 
-    progress = completed_sector_sum * 100 / block_mig_state.total_sector_sum;
+    if (block_mig_state.total_sector_sum != 0) {
+        progress = completed_sector_sum * 100 /
+                   block_mig_state.total_sector_sum;
+    } else {
+        progress = 100;
+    }
     if (progress != block_mig_state.prev_progress) {
         block_mig_state.prev_progress = progress;
         qemu_put_be64(f, (progress << BDRV_SECTOR_BITS)