From: Orit Wasserman <[email protected]> For example migration between Westmere and Nehelem hosts, caught in big real mode.
The code that fixes the segments for real mode guest was moved from enter_rmode to vmx_set_segments. enter_rmode calls vmx_set_segments for each segment. Signed-off-by: Orit Wasserman <[email protected]> Signed-off-by: Avi Kivity <[email protected]> (cherry picked from commit b246dd5df139501b974bd6b28f7815e53b3a792f) --- arch/x86/kvm/vmx.c | 70 ++++++++++++++++++++++++++++++++++++++++++++---------- 1 file changed, 58 insertions(+), 12 deletions(-) diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index 61593fd..86c8704 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -615,6 +615,10 @@ static void nested_release_page_clean(struct page *page) static void kvm_cpu_vmxoff(void); static void vmx_set_cr3(struct kvm_vcpu *vcpu, unsigned long cr3); static int vmx_set_tss_addr(struct kvm *kvm, unsigned int addr); +static void vmx_set_segment(struct kvm_vcpu *vcpu, + struct kvm_segment *var, int seg); +static void vmx_get_segment(struct kvm_vcpu *vcpu, + struct kvm_segment *var, int seg); static DEFINE_PER_CPU(struct vmcs *, vmxarea); static DEFINE_PER_CPU(struct vmcs *, current_vmcs); @@ -2763,6 +2767,7 @@ static void enter_rmode(struct kvm_vcpu *vcpu) { unsigned long flags; struct vcpu_vmx *vmx = to_vmx(vcpu); + struct kvm_segment var; if (enable_unrestricted_guest) return; @@ -2806,20 +2811,23 @@ static void enter_rmode(struct kvm_vcpu *vcpu) if (emulate_invalid_guest_state) goto continue_rmode; - vmcs_write16(GUEST_SS_SELECTOR, vmcs_readl(GUEST_SS_BASE) >> 4); - vmcs_write32(GUEST_SS_LIMIT, 0xffff); - vmcs_write32(GUEST_SS_AR_BYTES, 0xf3); + vmx_get_segment(vcpu, &var, VCPU_SREG_SS); + vmx_set_segment(vcpu, &var, VCPU_SREG_SS); + + vmx_get_segment(vcpu, &var, VCPU_SREG_CS); + vmx_set_segment(vcpu, &var, VCPU_SREG_CS); + + vmx_get_segment(vcpu, &var, VCPU_SREG_ES); + vmx_set_segment(vcpu, &var, VCPU_SREG_ES); - vmcs_write32(GUEST_CS_AR_BYTES, 0xf3); - vmcs_write32(GUEST_CS_LIMIT, 0xffff); - if (vmcs_readl(GUEST_CS_BASE) == 0xffff0000) - vmcs_writel(GUEST_CS_BASE, 0xf0000); - vmcs_write16(GUEST_CS_SELECTOR, vmcs_readl(GUEST_CS_BASE) >> 4); + vmx_get_segment(vcpu, &var, VCPU_SREG_DS); + vmx_set_segment(vcpu, &var, VCPU_SREG_DS); - fix_rmode_seg(VCPU_SREG_ES, &vmx->rmode.es); - fix_rmode_seg(VCPU_SREG_DS, &vmx->rmode.ds); - fix_rmode_seg(VCPU_SREG_GS, &vmx->rmode.gs); - fix_rmode_seg(VCPU_SREG_FS, &vmx->rmode.fs); + vmx_get_segment(vcpu, &var, VCPU_SREG_GS); + vmx_set_segment(vcpu, &var, VCPU_SREG_GS); + + vmx_get_segment(vcpu, &var, VCPU_SREG_FS); + vmx_set_segment(vcpu, &var, VCPU_SREG_FS); continue_rmode: kvm_mmu_reset_context(vcpu); @@ -3222,6 +3230,44 @@ static void vmx_set_segment(struct kvm_vcpu *vcpu, vmcs_write32(sf->ar_bytes, ar); __clear_bit(VCPU_EXREG_CPL, (ulong *)&vcpu->arch.regs_avail); + + /* + * Fix segments for real mode guest in hosts that don't have + * "unrestricted_mode" or it was disabled. + * This is done to allow migration of the guests from hosts with + * unrestricted guest like Westmere to older host that don't have + * unrestricted guest like Nehelem. + */ + if (!enable_unrestricted_guest && vmx->rmode.vm86_active) { + switch (seg) { + case VCPU_SREG_CS: + vmcs_write32(GUEST_CS_AR_BYTES, 0xf3); + vmcs_write32(GUEST_CS_LIMIT, 0xffff); + if (vmcs_readl(GUEST_CS_BASE) == 0xffff0000) + vmcs_writel(GUEST_CS_BASE, 0xf0000); + vmcs_write16(GUEST_CS_SELECTOR, + vmcs_readl(GUEST_CS_BASE) >> 4); + break; + case VCPU_SREG_ES: + fix_rmode_seg(VCPU_SREG_ES, &vmx->rmode.es); + break; + case VCPU_SREG_DS: + fix_rmode_seg(VCPU_SREG_DS, &vmx->rmode.ds); + break; + case VCPU_SREG_GS: + fix_rmode_seg(VCPU_SREG_GS, &vmx->rmode.gs); + break; + case VCPU_SREG_FS: + fix_rmode_seg(VCPU_SREG_FS, &vmx->rmode.fs); + break; + case VCPU_SREG_SS: + vmcs_write16(GUEST_SS_SELECTOR, + vmcs_readl(GUEST_SS_BASE) >> 4); + vmcs_write32(GUEST_SS_LIMIT, 0xffff); + vmcs_write32(GUEST_SS_AR_BYTES, 0xf3); + break; + } + } } static void vmx_get_cs_db_l_bits(struct kvm_vcpu *vcpu, int *db, int *l) -- 1.7.11.3 -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
