Re: [Qemu-devel] The first function called after migration for a block device

[Xiongzi Ge]

I tried. It invalidated the cache of the block device after migration. So, here, we can use a new cache for the block device after migration. Is it right?  I can implement a simple block driver in block/ directory.

On Mon, Jun 30, 2014 at 6:48 AM, Paolo Bonzini <address@hidden> wrote:

Il 28/06/2014 00:54, Xiongzi Ge ha scritto:

Hi Paolo,

Thanks. I found a function called bdrv_invalidate_cache() in qcow2.c.
After migration, it will be called to invalidate the cache of the block
device?

Let me quote again:

    This function has *nothing* to do with the guest OS's

    cache.  That cache is managed by the guest OS and, as I have already
    told you multiple times, there is *nothing* that QEMU can do about it.

    All you can do is use O_DIRECT in the guest.

Did you even *try* to understand this?!?

Paolo