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

[Paolo Bonzini <pbonzini@redhat.com>]

On 05/04/2016 12:48, Dr. David Alan Gilbert wrote:
> * Paolo Bonzini (pbonzini@redhat.com) 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...
> 
> Well, migration survives; how do I test if pflash is sane after migration?

Use "-S" on the destination and check if the file has the same contents.

Paolo

> Dave
> 
>> 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;
>>  }
> --
> Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK
>