Am 15.04.2016 um 14:19 hat Laszlo Ersek geschrieben:
> On 04/15/16 13:41, Dr. David Alan Gilbert (git) wrote:
> > From: "Dr. David Alan Gilbert" <dgilb...@redhat.com>
> >
> > Pflash migration (e.g. q35 + EFI variable storage) fails
> > with the assert:
> >
> > bdrv_co_do_pwritev: Assertion `!(bs->open_flags & 0x0800)' failed.
> >
> > This avoids the problem by delaying the pflash update until after
> > the device loads complete.
> >
> > Tested by:
> > Migrating Q35/EFI vm.
> > Changing efi variable content (with efiboot in the guest)
> > md5sum'ing the variable file before migration and after.
> >
> > This is a fix that Paolo posted in the message
> > 570244b3.4070...@redhat.com
> >
> > Signed-off-by: Paolo Bonzini <pbonz...@redhat.com>
> > Signed-off-by: Dr. David Alan Gilbert <dgilb...@redhat.com>
> > ---
> > hw/block/pflash_cfi01.c | 18 ++++++++++++++++--
> > 1 file changed, 16 insertions(+), 2 deletions(-)
> >
> > diff --git a/hw/block/pflash_cfi01.c b/hw/block/pflash_cfi01.c
> > index c475c2a..106a775 100644
> > --- a/hw/block/pflash_cfi01.c
> > +++ b/hw/block/pflash_cfi01.c
> > @@ -46,6 +46,7 @@
> > #include "exec/address-spaces.h"
> > #include "qemu/host-utils.h"
> > #include "hw/sysbus.h"
> > +#include "sysemu/sysemu.h"
> >
> > #define PFLASH_BUG(fmt, ...) \
> > do { \
> > @@ -97,6 +98,7 @@ struct pflash_t {
> > MemoryRegion mem;
> > char *name;
> > void *storage;
> > + VMChangeStateEntry *vmstate;
> > };
> >
> > static int pflash_post_load(void *opaque, int version_id);
> > @@ -944,13 +946,25 @@ MemoryRegion *pflash_cfi01_get_memory(pflash_t *fl)
> > return &fl->mem;
> > }
> >
> > +static void postload_update_cb(void *opaque, int running, RunState state)
> > +{
> > + pflash_t *pfl = opaque;
> > +
> > + /* This is called after bdrv_invalidate_cache_all. */
> > + qemu_del_vm_change_state_handler(pfl->vmstate);
> > + pfl->vmstate = NULL;
> > +
> > + DPRINTF("%s: updating bdrv for %s\n", __func__, pfl->name);
> > + pflash_update(pfl, 0, pfl->sector_len * pfl->nb_blocs);
> > +}
> > +
> > static int pflash_post_load(void *opaque, int version_id)
> > {
> > pflash_t *pfl = opaque;
> >
> > if (!pfl->ro) {
> > - DPRINTF("%s: updating bdrv for %s\n", __func__, pfl->name);
> > - pflash_update(pfl, 0, pfl->sector_len * pfl->nb_blocs);
> > + pfl->vmstate = qemu_add_vm_change_state_handler(postload_update_cb,
> > + pfl);
> > }
> > return 0;
> > }
> >
>
> I can't offer an in-depth review (I don't know migration internals /
> vmstate changes well enough, sorry), but I agree with the fix (and am
> thankful for it), and both the patch and the testing look good to me.
>
> Perhaps some assert()s could be added to postload_update_cb(), about
> "running" and "state", but I'm not certain.
>
> Acked-by: Laszlo Ersek <ler...@redhat.com>
Thanks, applied to the block branch.
Kevin
