Re: [PATCH] migration: Fix migration crash when target psize larger than host

[Thomas Huth <thuth@redhat.com>]

On 20/01/2023 17.31, Peter Xu wrote:
> Commit d9e474ea56 overlooked the case where the target psize is even larger
> than the host psize.  One example is Alpha has 8K page size and migration
> will start to crash the source QEMU when running Alpha migration on x86.
> 
> Fix it by detecting that case and set host start/end just to cover the
> single page to be migrated.
> 
> This will slightly optimize the common case where host psize equals to
> guest psize so we don't even need to do the roundups, but that's trivial.
> 
> Cc: qemu-stable@nongnu.org
> Reported-by: Thomas Huth <thuth@redhat.com>
> Resolves: https://gitlab.com/qemu-project/qemu/-/issues/1456
> Fixes: d9e474ea56 ("migration: Teach PSS about host page")
> Signed-off-by: Peter Xu <peterx@redhat.com>
> ---
>   migration/ram.c | 21 +++++++++++++++++++--
>   1 file changed, 19 insertions(+), 2 deletions(-)

Thanks, I've checked that this fixes the issue for me, indeed!

Tested-by: Thomas Huth <thuth@redhat.com>