diff options
| author | Avi Kivity <avi@qumranet.com> | 2007-01-05 16:36:51 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@woody.osdl.org> | 2007-01-05 23:55:26 -0800 |
| commit | 32b35627355c3bf17e1903efd117efed7653a54e (patch) | |
| tree | 9ef6ca5a32f6e224f4d463a89c21dda2ac08eafe | |
| parent | 3bb65a22a4502067f8cd3cb4c923ffa70be62091 (diff) | |
| download | lwn-32b35627355c3bf17e1903efd117efed7653a54e.tar.gz lwn-32b35627355c3bf17e1903efd117efed7653a54e.zip | |
[PATCH] KVM: MMU: Fix cmpxchg8b emulation
cmpxchg8b uses edx:eax as the compare operand, not edi:eax.
cmpxchg8b is used by 32-bit pae guests to set page table entries atomically,
and this is emulated touching shadowed guest page tables.
Also, implement it for 32-bit hosts.
Signed-off-by: Avi Kivity <avi@qumranet.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
| -rw-r--r-- | drivers/kvm/kvm_main.c | 27 | ||||
| -rw-r--r-- | drivers/kvm/x86_emulate.c | 2 |
2 files changed, 28 insertions, 1 deletions
diff --git a/drivers/kvm/kvm_main.c b/drivers/kvm/kvm_main.c index cec10106ce77..2e6bc5659953 100644 --- a/drivers/kvm/kvm_main.c +++ b/drivers/kvm/kvm_main.c @@ -936,6 +936,30 @@ static int emulator_cmpxchg_emulated(unsigned long addr, return emulator_write_emulated(addr, new, bytes, ctxt); } +#ifdef CONFIG_X86_32 + +static int emulator_cmpxchg8b_emulated(unsigned long addr, + unsigned long old_lo, + unsigned long old_hi, + unsigned long new_lo, + unsigned long new_hi, + struct x86_emulate_ctxt *ctxt) +{ + static int reported; + int r; + + if (!reported) { + reported = 1; + printk(KERN_WARNING "kvm: emulating exchange8b as write\n"); + } + r = emulator_write_emulated(addr, new_lo, 4, ctxt); + if (r != X86EMUL_CONTINUE) + return r; + return emulator_write_emulated(addr+4, new_hi, 4, ctxt); +} + +#endif + static unsigned long get_segment_base(struct kvm_vcpu *vcpu, int seg) { return kvm_arch_ops->get_segment_base(vcpu, seg); @@ -1010,6 +1034,9 @@ struct x86_emulate_ops emulate_ops = { .read_emulated = emulator_read_emulated, .write_emulated = emulator_write_emulated, .cmpxchg_emulated = emulator_cmpxchg_emulated, +#ifdef CONFIG_X86_32 + .cmpxchg8b_emulated = emulator_cmpxchg8b_emulated, +#endif }; int emulate_instruction(struct kvm_vcpu *vcpu, diff --git a/drivers/kvm/x86_emulate.c b/drivers/kvm/x86_emulate.c index 1bff3e925fda..be70795b4822 100644 --- a/drivers/kvm/x86_emulate.c +++ b/drivers/kvm/x86_emulate.c @@ -1323,7 +1323,7 @@ twobyte_special_insn: ctxt)) != 0)) goto done; if ((old_lo != _regs[VCPU_REGS_RAX]) - || (old_hi != _regs[VCPU_REGS_RDI])) { + || (old_hi != _regs[VCPU_REGS_RDX])) { _regs[VCPU_REGS_RAX] = old_lo; _regs[VCPU_REGS_RDX] = old_hi; _eflags &= ~EFLG_ZF; |