Re: [PATCH] Revert "memory: Optimize replay of guest mapping"

[Peter Maydell]

On Tue, 4 Apr 2023 at 23:04, Philippe Mathieu-Daudé <philmd@linaro.org> wrote:
>
> On 4/4/23 22:37, Michael S. Tsirkin wrote:
> > From: Peter Maydell <peter.maydell@linaro.org>
> >
> > This reverts commit 6da24341866fa940fd7d575788a2319514941c77
> > ("memory: Optimize replay of guest mapping").
> >
> > This change breaks the mps3-an547 board under TCG (and
> > probably other TCG boards using an IOMMU), which now
> > assert:
> >
> > $ ./build/x86/qemu-system-arm --machine mps3-an547 -serial stdio
> > -kernel /tmp/an547-mwe/build/test.elf
> > qemu-system-arm: ../../softmmu/memory.c:1903:
> > memory_region_register_iommu_notifier: Assertion `n->end <=
> > memory_region_size(mr)' failed.
> >
> > This is because tcg_register_iommu_notifier() registers
> > an IOMMU notifier which covers the entire address space,
> > so the assertion added in this commit is not correct.
> >
> > For the 8.0 release, just revert this commit as it is
> > only an optimization.
> >
> > Fixes: 6da24341866f ("memory: Optimize replay of guest mapping")
> > Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
> > Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
> > ---
> >
> > completely untested but Pater asked help in sending this.
> >
> >   hw/i386/intel_iommu.c | 2 +-
> >   softmmu/memory.c      | 4 ++--
> >   2 files changed, 3 insertions(+), 3 deletions(-)
>
> Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>

Thanks; I have applied this to master to fix the assertion failure
for rc3.

-- PMM