Re: [Qemu-devel] efi var store migration assert (bdrv_co_do_pwritev: Assertion `!(bs->open_flags & 0x0800)' failed.)

[Peter Maydell]

On 4 April 2016 at 11:40, Paolo Bonzini <address@hidden> wrote:
>
>
> On 01/04/2016 19:58, Dr. David Alan Gilbert wrote:
>> In the continuing journeys of trying to migrate a q35 guest with ovmf,
>> I've just hit this assert:
>>
>> qemu-system-x86_64: /root/git/qemu/block/io.c:1297: bdrv_co_do_pwritev: 
>> Assertion `!(bs->open_flags & 0x0800)' failed.
>>
>> This is just ahead of rc0 - 1458317c8ada834cf39287f6d11a8cb8a37360d6 from 
>> yesterday.
>
> Try this...

Hi Paolo -- this bug is on the list of "things we should probably
fix for 2.6", but your fix below doesn't have your Signed-off-by
line. Were you planning to send this as a proper patch, or could
you provide an s-o-b line so somebody else (David?) can take the
code and clean it up into an actual patch?

thanks
-- PMM

>
> Paolo
>
> diff --git a/hw/block/pflash_cfi01.c b/hw/block/pflash_cfi01.c
> index c475c2a..e96a7b0 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 +946,24 @@ 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;
>  }