Re: [PATCH-for-9.0 v2 0/3] system/physmem: Fix migration dirty bitmap coherency with TCG memory access

[Nicholas Piggin]

On Wed Mar 13, 2024 at 7:09 AM AEST, Peter Xu wrote:
> On Tue, Mar 12, 2024 at 09:14:55PM +0100, Philippe Mathieu-Daudé wrote:
> > Respin of Nicholas patch, without introducing
> > tcg_cpu_physical_memory_dirty_bits_cleared(),
> > and split in more digestible parts.
> > 
> > Nicholas Piggin (2):
> >   physmem: Factor cpu_physical_memory_dirty_bits_cleared() out
> >   physmem: Fix migration dirty bitmap coherency with TCG memory access
> > 
> > Philippe Mathieu-Daudé (1):
> >   physmem: Expose tlb_reset_dirty_range_all()
> > 
> >  include/exec/exec-all.h |  1 +
> >  include/exec/ram_addr.h | 12 ++++++++++++
> >  system/physmem.c        | 10 ++++------
> >  3 files changed, 17 insertions(+), 6 deletions(-)
>
> Yes agree a better split than the single patch.  Tentatively queued while
> waiting for any comments.

I've run into several other possible races / lost dirty tracking
when stressing this stuff, but this one was the easiest to hit and
most obvious and simple fix, so I think it's still good to go.

Also have a qtest test case that can reproduce this one so I'll
send that after this is merged. It's really just the migration
test case with value verification added in.

Thanks,
Nick