KVM: PPC: Book3E: KVM HV host module doesn't work anymore

[Paolo Bonzini]

On Thu, Dec 26, 2024 at 3:26 PM Christian Zigotzky
<chzigotzky at xenosoft.de> wrote:
> This has solved the issue:
>
> cp linux-6.12.6/arch/powerpc/kvm/e500_mmu_host.c
> a/arch/powerpc/kvm/e500_mmu_host.c
> cp linux-6.12.6/include/linux/kvm_host.h a/include/linux/kvm_host.h
> cp linux-6.12.6/virt/kvm/kvm_main.c a/virt/kvm/kvm_main.c
> cp linux-6.12.6/virt/kvm/kvm_mm.h a/virt/kvm/kvm_mm.h

Yes, those are exactly the file touched in the bisection result and in
my patch. However, reverting blindly like this would break the build
for all other architectures, and reintroduce the bugs which were fixed
by the change.

The patch in https://github.com/user-attachments/files/18238781/kvm_main.patch
is incorrect (the "*writable = false" line was not removed, thus
leaving in the NULL pointer dereference).  Please test the
kvm-e500-bisection-rebase branch of
https://git.kernel.org/pub/scm/virt/kvm/kvm.git, which has the patch
applied already:

- first test commit 0096d3855a5e80b9d4e43e5a291e8c79aa4abbc2, and
report if it fails

- then the entire branch, bisecting between
0096d3855a5e80b9d4e43e5a291e8c79aa4abbc2 and the top if it fails.

Paolo