patches/kernel/0023-KVM-x86-emulator-update-the-emulation-mode-after-rsm.patch

   1 From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
   2 From: Maxim Levitsky <mlevitsk@redhat.com>
   3 Date: Tue, 21 Jun 2022 18:08:55 +0300
   4 Subject: [PATCH] KVM: x86: emulator: update the emulation mode after rsm
   5
   6 This ensures that RIP will be correctly written back,
   7 because the RSM instruction can switch the CPU mode from
   8 32 bit (or less) to 64 bit.
   9
  10 This fixes a guest crash in case the #SMI is received
  11 while the guest runs a code from an address > 32 bit.
  12
  13 Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
  14 Signed-off-by: Thomas Lamprecht <t.lamprecht@proxmox.com>
  15 ---
  16  arch/x86/kvm/emulate.c | 5 +++++
  17  1 file changed, 5 insertions(+)
  18
  19 diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
  20 index c4e3f9103870..03a761397599 100644
  21 --- a/arch/x86/kvm/emulate.c
  22 +++ b/arch/x86/kvm/emulate.c
  23 @@ -2650,6 +2650,11 @@ static int em_rsm(struct x86_emulate_ctxt *ctxt)
  24         if (ret != X86EMUL_CONTINUE)
  25                 goto emulate_shutdown;
  26
  27 +
  28 +       ret = update_emulation_mode(ctxt);
  29 +       if (ret != X86EMUL_CONTINUE)
  30 +               goto emulate_shutdown;
  31 +
  32         /*
  33          * Note, the ctxt->ops callbacks are responsible for handling side
  34          * effects when writing MSRs and CRs, e.g. MMU context resets, CPUID