On Wed, Sep 11, 2019 at 05:51:05PM +0200, Paolo Bonzini wrote: > On 27/08/19 15:07, Jan Dakinevich wrote: > > This series intended to fix (again) a bug that was a subject of the > > following change: > > > > 6ea6e84 ("KVM: x86: inject exceptions produced by x86_decode_insn") > > > > Suddenly, that fix had a couple mistakes. First, ctxt->have_exception was > > not set if fault happened during instruction decoding. Second, returning > > value of inject_emulated_instruction was used to make the decision to > > reenter guest, but this could happen iff on nested page fault, that is not > > the scope where this bug could occur. > > > > However, I have still deep doubts about 3rd commit in the series. Could > > you please, make me an advise if it is the correct handling of guest page > > fault? > > > > Jan Dakinevich (3): > > KVM: x86: fix wrong return code > > KVM: x86: set ctxt->have_exception in x86_decode_insn() > > KVM: x86: always stop emulation on page fault > > > > arch/x86/kvm/emulate.c | 4 +++- > > arch/x86/kvm/x86.c | 4 +++- > > 2 files changed, 6 insertions(+), 2 deletions(-) > > > > Queued, thanks. I added the WARN_ON_ONCE that Sean suggested. Which version did you queue? It sounds like you queued v1, which breaks VMware backdoor emulation due to incorrect patch ordering. v3[*] fixes the ordering issue and adds the WARN_ON_ONCE. [*] https://patchwork.kernel.org/cover/11120627/