From 89551ed005c8615add5ae08174c84b22bf90fc7c Mon Sep 17 00:00:00 2001 From: "kaf24@firebug.cl.cam.ac.uk" Date: Wed, 31 May 2006 07:32:55 +0100 Subject: [PATCH] [HVM] Fix a bug in the emulation of the xchg instruction. This bug has prevented us from booting fully virtualized SMP guests that write to the APIC using the xchg instruction (when CONFIG_X86_GOOD_APIC is not set). On 32 bit platforms, sles 10 kernels are built without CONFIG_x86_GOOD_APIC not set and hence we have had problems booting fully virtualized SMP sles 10 guests. Signed-off-by: K. Y. Srinivasan xen-unstable changeset: 10179:5be9e927533d94ed1389f8926d51c65849133556 xen-unstable date: Tue May 30 12:30:47 2006 +0100 --- xen/arch/x86/hvm/io.c | 10 ++++++++++ xen/arch/x86/hvm/platform.c | 24 ++++++++++++++++++++---- 2 files changed, 30 insertions(+), 4 deletions(-) diff --git a/xen/arch/x86/hvm/io.c b/xen/arch/x86/hvm/io.c index 893dd68ce..336d5d9bd 100644 --- a/xen/arch/x86/hvm/io.c +++ b/xen/arch/x86/hvm/io.c @@ -646,6 +646,16 @@ static void hvm_mmio_assist(struct vcpu *v, struct cpu_user_regs *regs, regs->eflags &= ~X86_EFLAGS_CF; break; + + case INSTR_XCHG: + if (src & REGISTER) { + index = operand_index(src); + set_reg_value(size, index, 0, regs, p->u.data); + } else { + index = operand_index(dst); + set_reg_value(size, index, 0, regs, p->u.data); + } + break; } hvm_load_cpu_guest_regs(v, regs); diff --git a/xen/arch/x86/hvm/platform.c b/xen/arch/x86/hvm/platform.c index 1206ebda9..20779414f 100644 --- a/xen/arch/x86/hvm/platform.c +++ b/xen/arch/x86/hvm/platform.c @@ -954,10 +954,26 @@ void handle_mmio(unsigned long va, unsigned long gpa) mmio_opp->instr = mmio_inst.instr; mmio_opp->operand[0] = mmio_inst.operand[0]; /* source */ mmio_opp->operand[1] = mmio_inst.operand[1]; /* destination */ - - /* send the request and wait for the value */ - send_mmio_req(IOREQ_TYPE_XCHG, gpa, 1, - mmio_inst.op_size, 0, IOREQ_WRITE, 0); + if (mmio_inst.operand[0] & REGISTER) { + long value; + unsigned long operand = mmio_inst.operand[0]; + value = get_reg_value(operand_size(operand), + operand_index(operand), 0, + mmio_opp->inst_decoder_regs); + /* send the request and wait for the value */ + send_mmio_req(IOREQ_TYPE_XCHG, gpa, 1, + mmio_inst.op_size, value, IOREQ_WRITE, 0); + } else { + /* the destination is a register */ + long value; + unsigned long operand = mmio_inst.operand[1]; + value = get_reg_value(operand_size(operand), + operand_index(operand), 0, + mmio_opp->inst_decoder_regs); + /* send the request and wait for the value */ + send_mmio_req(IOREQ_TYPE_XCHG, gpa, 1, + mmio_inst.op_size, value, IOREQ_WRITE, 0); + } break; default: -- 2.39.5