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  1. 01 8月, 2011 1 次提交
  3. 22 7月, 2011 1 次提交
  5. 05 7月, 2011 2 次提交
  7. 24 6月, 2011 1 次提交
  9. 08 6月, 2011 1 次提交
  11. 19 5月, 2011 2 次提交
  13. 07 4月, 2011 1 次提交
    • R
      Do not delete BlockDriverState when deleting the drive · d22b2f41
      由 Ryan Harper 提交于 
      When removing a drive from the host-side via drive_del we currently have
the following path:

drive_del
qemu_aio_flush()
bdrv_close()    // zaps bs->drv, which makes any subsequent I/O get
                // dropped.  Works as designed
drive_uninit()
bdrv_delete()   // frees the bs.  Since the device is still connected to
                // bs, any subsequent I/O is a use-after-free.

The value of bs->drv becomes unpredictable on free.  As long as it
remains null, I/O still gets dropped, however it could become non-null
at any point after the free resulting SEGVs or other QEMU state
corruption.

To resolve this issue as simply as possible, we can chose to not
actually delete the BlockDriverState pointer.  Since bdrv_close()
handles setting the drv pointer to NULL, we just need to remove the
BlockDriverState from the QLIST that is used to enumerate the block
devices.  This is currently handled within bdrv_delete, so move this
into its own function, bdrv_make_anon().

The result is that we can now invoke drive_del, this closes the file
descriptors and sets BlockDriverState->drv to NULL which prevents futher
IO to the device, and since we do not free BlockDriverState, we don't
have to worry about the copy retained in the block devices.

We also don't attempt to remove the qdev property since we are no longer
deleting the BlockDriverState on drives with associated drives.  This
also allows for removing Drives with no devices associated either.
Reported-by: NMarkus Armbruster <armbru@redhat.com>
Signed-off-by: NRyan Harper <ryanh@us.ibm.com>
Acked-by: NMarkus Armbruster <armbru@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
      d22b2f41
  15. 04 4月, 2011 1 次提交
  17. 15 3月, 2011 1 次提交
    • J
      Improve error handling in do_snapshot_blkdev() · 52f9a172
      由 Jes Sorensen 提交于 
      In case we cannot open the newly created snapshot image, try to fall
back to the original image file and continue running on that, which
should prevent the guest from aborting.

This is a corner case which can happen if the admin by mistake
specifies the snapshot file on a virtual file system which does not
support O_DIRECT. bdrv_create() does not use O_DIRECT, but the
following open in bdrv_open() does and will then fail.
Signed-off-by: NJes Sorensen <Jes.Sorensen@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
      52f9a172
  19. 10 2月, 2011 2 次提交
  21. 07 2月, 2011 2 次提交
  23. 31 1月, 2011 10 次提交
  25. 24 1月, 2011 4 次提交
  27. 17 12月, 2010 2 次提交
  29. 25 11月, 2010 1 次提交
    • R
      Implement drive_del to decouple block removal from device removal · 9063f814
      由 Ryan Harper 提交于 
      Currently device hotplug removal code is tied to device removal via
ACPI.  All pci devices that are removable via device_del() require the
guest to respond to the request.  In some cases the guest may not
respond leaving the device still accessible to the guest.  The management
layer doesn't currently have a reliable way to revoke access to host
resource in the presence of an uncooperative guest.

This patch implements a new monitor command, drive_del, which
provides an explicit command to revoke access to a host block device.

drive_del first quiesces the block device (qemu_aio_flush;
bdrv_flush() and bdrv_close()).  This prevents further IO from being
submitted against the host device.  Finally, drive_del cleans up
pointers between the drive object (host resource) and the device
object (guest resource).
Signed-off-by: NRyan Harper <ryanh@us.ibm.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
      9063f814
  31. 04 11月, 2010 1 次提交
  33. 23 8月, 2010 1 次提交
  35. 26 7月, 2010 1 次提交
  37. 06 7月, 2010 1 次提交
  39. 02 7月, 2010 4 次提交