On 02/13/2010 10:40 PM, Stefan Weil wrote:
This command used to work, but fails now:
$ i386-softmmu/qemu -snapshot /dev/sda
qemu: could not open disk image /dev/sda: Permission denied
$ ls -l /dev/sda
brw-rw-r-- 1 root disk 8, 0 13. Feb 08:55 /dev/sda
The original file of a snapshot needs only read access,
but QEMU tries read/write access and fails.
Variants of above command using -hda or -drive
also fail with the same error message.
I did not test whether the regression affects other
kinds of images, too. Maybe only raw images trigger
no longer work.
Caused by
commit 03cbdac7efc20994d0a87015e24e835d0139df7b
Author: Naphtali Sprei <nsp...@redhat.com> 2010-01-17 15:48:15
Committer: Anthony Liguori <aligu...@us.ibm.com> 2010-01-20 15:25:22
Follows: v0.12.0-rc0
Disable fall-back to read-only when cannot open drive's file for
read-write
Signed-off-by: Naphtali Sprei <nsp...@redhat.com>
Signed-off-by: Anthony Liguori <aligu...@us.ibm.com>
... because before that it was working like this:
open("/dev/sda", O_RDWR|O_SYNC|O_CLOEXEC) = -1 EACCES
open("/dev/sda", O_RDONLY|O_SYNC|O_CLOEXEC) = 10
BTW, because of other bugs in the middle of the history you need a
command line "-hda /dev/null -drive file=/dev/sda,snapshot=on" to bisect it.
Paolo
