[Qemu-commits] [qemu/qemu] ed7b70: migration/block-dirty-bitmap: fix larger granulari...

[Peter Maydell]

  Branch: refs/heads/master
  Home:   https://github.com/qemu/qemu
  Commit: ed7b70c27b5c11ff4800e608d301cd7a36b81c5e
      
https://github.com/qemu/qemu/commit/ed7b70c27b5c11ff4800e608d301cd7a36b81c5e
  Author: Stefan Reiter <s.reiter@proxmox.com>
  Date:   2020-10-26 (Mon, 26 Oct 2020)

  Changed paths:
    M migration/block-dirty-bitmap.c

  Log Message:
  -----------
  migration/block-dirty-bitmap: fix larger granularity bitmaps

sectors_per_chunk is a 64 bit integer, but the calculation is done in 32
bits, leading to an overflow for coarse bitmap granularities.

If that results in the value 0, it leads to a hang where no progress is
made but send_bitmap_bits is constantly called with nr_sectors being 0.

Signed-off-by: Stefan Reiter <s.reiter@proxmox.com>
Message-Id: <20201021144456.1072-1-s.reiter@proxmox.com>
Fixes: b35ebdf07 migration: add postcopy migration of dirty bitmaps
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
[eblake: Use correct type for 8ULL, use () to avoid overflow]
Signed-off-by: Eric Blake <eblake@redhat.com>


  Commit: a024890a64085d3d37ad7eda164775251285c14c
      
https://github.com/qemu/qemu/commit/a024890a64085d3d37ad7eda164775251285c14c
  Author: Chen Qun <kuhn.chenqun@huawei.com>
  Date:   2020-10-26 (Mon, 26 Oct 2020)

  Changed paths:
    M migration/block-dirty-bitmap.c

  Log Message:
  -----------
  migration/block-dirty-bitmap: fix uninitialized variable warning

A default value is provided for the variable 'bitmap_name' to avoid
a compiler warning.

The compiler showed the warning:
migration/block-dirty-bitmap.c:1090:13: warning: ‘bitmap_name’
may be used uninitialized in this function [-Wmaybe-uninitialized]
       g_strlcpy(s->bitmap_name, bitmap_name, sizeof(s->bitmap_name));
       ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Reported-by: Euler Robot <euler.robot@huawei.com>
Signed-off-by: Chen Qun <kuhn.chenqun@huawei.com>
Message-Id: <20201014114430.1898684-1-kuhn.chenqun@huawei.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
[eblake: commit message grammar tweaks]
Signed-off-by: Eric Blake <eblake@redhat.com>


  Commit: 091e3e3dbc499d84c004e1c50bc9870af37f6e99
      
https://github.com/qemu/qemu/commit/091e3e3dbc499d84c004e1c50bc9870af37f6e99
  Author: Peter Maydell <peter.maydell@linaro.org>
  Date:   2020-10-26 (Mon, 26 Oct 2020)

  Changed paths:
    M migration/block-dirty-bitmap.c

  Log Message:
  -----------
  Merge remote-tracking branch 'remotes/ericb/tags/pull-bitmaps-2020-10-26' 
into staging

bitmaps patches for 2020-10-26

- fix infloop on large bitmap granularity
- silence compiler warning

# gpg: Signature made Mon 26 Oct 2020 11:56:54 GMT
# gpg:                using RSA key 71C2CC22B1C4602927D2F3AAA7A16B4A2527436A
# gpg: Good signature from "Eric Blake <eblake@redhat.com>" [full]
# gpg:                 aka "Eric Blake (Free Software Programmer) 
<ebb9@byu.net>" [full]
# gpg:                 aka "[jpeg image of size 6874]" [full]
# Primary key fingerprint: 71C2 CC22 B1C4 6029 27D2  F3AA A7A1 6B4A 2527 436A

* remotes/ericb/tags/pull-bitmaps-2020-10-26:
  migration/block-dirty-bitmap: fix uninitialized variable warning
  migration/block-dirty-bitmap: fix larger granularity bitmaps

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>


Compare: https://github.com/qemu/qemu/compare/1dc887329a10...091e3e3dbc49