From 4ba1d9d1ac06a9a14a03ab0882b762533be96b97 Mon Sep 17 00:00:00 2001 From: Jan Beulich Date: Tue, 17 May 2011 13:55:45 +0100 Subject: [PATCH] x86: further adjustments to arch_set_info_guest() after c/s 23142:f5e8d152a565 The adjustments to v->arch.user_regs.eflags and the initialization of the int80 direct trap must be done earlier (namely before the function may bail because of inconsistencies between input and stored state on an already initialised vCPU) so that stored state is consistent, and for arch_get_info_guest() to not have its eflags related BUG_ON() triggered. Further, v->arch.pv_vcpu.ctrlreg[] indices 3 and 1 aren't being kept up to date while the domain is running, so consistency checks must instead be done against v->arch.guest_table{,_user}. Additionally, for 64-bit pv domains, CR1 must also be checked to be consistent with the kernel mode setting for the vCPU, and the whole CR1 checking should not be done for 32-bit pv domains. Signed-off-by: Jan Beulich --- xen/arch/x86/domain.c | 38 +++++++++++++++++++++++++++----------- 1 file changed, 27 insertions(+), 11 deletions(-) diff --git a/xen/arch/x86/domain.c b/xen/arch/x86/domain.c index 8bb0f5dd81..f5f6fcfe2a 100644 --- a/xen/arch/x86/domain.c +++ b/xen/arch/x86/domain.c @@ -843,6 +843,15 @@ int arch_set_info_guest( goto out; } + init_int80_direct_trap(v); + + /* IOPL privileges are virtualised. */ + v->arch.pv_vcpu.iopl = (v->arch.user_regs.eflags >> 12) & 3; + v->arch.user_regs.eflags &= ~X86_EFLAGS_IOPL; + + /* Ensure real hardware interrupts are enabled. */ + v->arch.user_regs.eflags |= X86_EFLAGS_IF; + if ( !v->is_initialised ) { v->arch.pv_vcpu.ldt_base = c(ldt_base); @@ -850,11 +859,27 @@ int arch_set_info_guest( } else { - bool_t fail = v->arch.pv_vcpu.ctrlreg[3] != c(ctrlreg[3]); + unsigned long pfn = pagetable_get_pfn(v->arch.guest_table); + bool_t fail; + if ( !compat ) + { + fail = xen_pfn_to_cr3(pfn) != c.nat->ctrlreg[3]; #ifdef CONFIG_X86_64 - fail |= v->arch.pv_vcpu.ctrlreg[1] != c(ctrlreg[1]); + if ( pagetable_is_null(v->arch.guest_table_user) ) + fail |= c.nat->ctrlreg[1] || !(flags & VGCF_in_kernel); + else + { + pfn = pagetable_get_pfn(v->arch.guest_table_user); + fail |= xen_pfn_to_cr3(pfn) != c.nat->ctrlreg[1]; + } + } else { + l4_pgentry_t *l4tab = __va(pfn_to_paddr(pfn)); + + pfn = l4e_get_pfn(*l4tab); + fail = compat_pfn_to_cr3(pfn) != c.cmp->ctrlreg[3]; #endif + } for ( i = 0; i < ARRAY_SIZE(v->arch.pv_vcpu.gdt_frames); ++i ) fail |= v->arch.pv_vcpu.gdt_frames[i] != c(gdt_frames[i]); @@ -894,15 +919,6 @@ int arch_set_info_guest( v->arch.pv_vcpu.ctrlreg[0] &= X86_CR0_TS; v->arch.pv_vcpu.ctrlreg[0] |= read_cr0() & ~X86_CR0_TS; - init_int80_direct_trap(v); - - /* IOPL privileges are virtualised. */ - v->arch.pv_vcpu.iopl = (v->arch.user_regs.eflags >> 12) & 3; - v->arch.user_regs.eflags &= ~X86_EFLAGS_IOPL; - - /* Ensure real hardware interrupts are enabled. */ - v->arch.user_regs.eflags |= X86_EFLAGS_IF; - cr4 = v->arch.pv_vcpu.ctrlreg[4]; v->arch.pv_vcpu.ctrlreg[4] = cr4 ? pv_guest_cr4_fixup(v, cr4) : real_cr4_to_pv_guest_cr4(mmu_cr4_features); -- 2.30.2