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| author |   Nadav Amit <namit@cs.technion.ac.il> | 2014-11-02 11:54:41 +0200 |
|---|---|---|
| committer |   Paolo Bonzini <pbonzini@redhat.com> | 2014-11-07 15:44:01 +0100 |
| commit | 5b38ab877e5bd6c6564f2f23f25e0c3d4768728a (patch) | |
| tree | 707c85940c630b7d0aa61eb0cfe2c4fef9d2c381 /arch/x86/kvm | |
| parent | KVM: x86: reset RVI upon system reset (diff) | |
| download | linux-dev-5b38ab877e5bd6c6564f2f23f25e0c3d4768728a.tar.xz linux-dev-5b38ab877e5bd6c6564f2f23f25e0c3d4768728a.zip | |
KVM: x86: decode_modrm does not regard modrm correctly
In one occassion, decode_modrm uses the rm field after it is extended with
REX.B to determine the addressing mode. Doing so causes it not to read the
offset for rip-relative addressing with REX.B=1.
This patch moves the fetch where we already mask REX.B away instead.
Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'arch/x86/kvm')
| -rw-r--r-- | arch/x86/kvm/emulate.c | 5 |
1 files changed, 1 insertions, 4 deletions
diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c index cd2029bbab48..a4703eb9c1ed 100644 --- a/arch/x86/kvm/emulate.c +++ b/arch/x86/kvm/emulate.c @@ -1223,6 +1223,7 @@ static int decode_modrm(struct x86_emulate_ctxt *ctxt, if (index_reg != 4) modrm_ea += reg_read(ctxt, index_reg) << scale; } else if ((ctxt->modrm_rm & 7) == 5 && ctxt->modrm_mod == 0) { + modrm_ea += insn_fetch(s32, ctxt); if (ctxt->mode == X86EMUL_MODE_PROT64) ctxt->rip_relative = 1; } else { @@ -1231,10 +1232,6 @@ static int decode_modrm(struct x86_emulate_ctxt *ctxt, adjust_modrm_seg(ctxt, base_reg); } switch (ctxt->modrm_mod) { - case 0: - if (ctxt->modrm_rm == 5) - modrm_ea += insn_fetch(s32, ctxt); - break; case 1: modrm_ea += insn_fetch(s8, ctxt); break; |