diff options
Diffstat (limited to 'arch/x86/kvm/emulate.c')
-rw-r--r-- | arch/x86/kvm/emulate.c | 355 |
1 files changed, 2 insertions, 353 deletions
diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c index 4a43261d25a2..5cc3efa0e21c 100644 --- a/arch/x86/kvm/emulate.c +++ b/arch/x86/kvm/emulate.c @@ -242,37 +242,6 @@ enum x86_transfer_type { X86_TRANSFER_TASK_SWITCH, }; -static ulong reg_read(struct x86_emulate_ctxt *ctxt, unsigned nr) -{ - if (KVM_EMULATOR_BUG_ON(nr >= NR_EMULATOR_GPRS, ctxt)) - nr &= NR_EMULATOR_GPRS - 1; - - if (!(ctxt->regs_valid & (1 << nr))) { - ctxt->regs_valid |= 1 << nr; - ctxt->_regs[nr] = ctxt->ops->read_gpr(ctxt, nr); - } - return ctxt->_regs[nr]; -} - -static ulong *reg_write(struct x86_emulate_ctxt *ctxt, unsigned nr) -{ - if (KVM_EMULATOR_BUG_ON(nr >= NR_EMULATOR_GPRS, ctxt)) - nr &= NR_EMULATOR_GPRS - 1; - - BUILD_BUG_ON(sizeof(ctxt->regs_dirty) * BITS_PER_BYTE < NR_EMULATOR_GPRS); - BUILD_BUG_ON(sizeof(ctxt->regs_valid) * BITS_PER_BYTE < NR_EMULATOR_GPRS); - - ctxt->regs_valid |= 1 << nr; - ctxt->regs_dirty |= 1 << nr; - return &ctxt->_regs[nr]; -} - -static ulong *reg_rmw(struct x86_emulate_ctxt *ctxt, unsigned nr) -{ - reg_read(ctxt, nr); - return reg_write(ctxt, nr); -} - static void writeback_registers(struct x86_emulate_ctxt *ctxt) { unsigned long dirty = ctxt->regs_dirty; @@ -2338,335 +2307,15 @@ static int em_lseg(struct x86_emulate_ctxt *ctxt) return rc; } -static int emulator_has_longmode(struct x86_emulate_ctxt *ctxt) -{ -#ifdef CONFIG_X86_64 - return ctxt->ops->guest_has_long_mode(ctxt); -#else - return false; -#endif -} - -static void rsm_set_desc_flags(struct desc_struct *desc, u32 flags) -{ - desc->g = (flags >> 23) & 1; - desc->d = (flags >> 22) & 1; - desc->l = (flags >> 21) & 1; - desc->avl = (flags >> 20) & 1; - desc->p = (flags >> 15) & 1; - desc->dpl = (flags >> 13) & 3; - desc->s = (flags >> 12) & 1; - desc->type = (flags >> 8) & 15; -} - -static int rsm_load_seg_32(struct x86_emulate_ctxt *ctxt, const char *smstate, - int n) -{ - struct desc_struct desc; - int offset; - u16 selector; - - selector = GET_SMSTATE(u32, smstate, 0x7fa8 + n * 4); - - if (n < 3) - offset = 0x7f84 + n * 12; - else - offset = 0x7f2c + (n - 3) * 12; - - set_desc_base(&desc, GET_SMSTATE(u32, smstate, offset + 8)); - set_desc_limit(&desc, GET_SMSTATE(u32, smstate, offset + 4)); - rsm_set_desc_flags(&desc, GET_SMSTATE(u32, smstate, offset)); - ctxt->ops->set_segment(ctxt, selector, &desc, 0, n); - return X86EMUL_CONTINUE; -} - -#ifdef CONFIG_X86_64 -static int rsm_load_seg_64(struct x86_emulate_ctxt *ctxt, const char *smstate, - int n) -{ - struct desc_struct desc; - int offset; - u16 selector; - u32 base3; - - offset = 0x7e00 + n * 16; - - selector = GET_SMSTATE(u16, smstate, offset); - rsm_set_desc_flags(&desc, GET_SMSTATE(u16, smstate, offset + 2) << 8); - set_desc_limit(&desc, GET_SMSTATE(u32, smstate, offset + 4)); - set_desc_base(&desc, GET_SMSTATE(u32, smstate, offset + 8)); - base3 = GET_SMSTATE(u32, smstate, offset + 12); - - ctxt->ops->set_segment(ctxt, selector, &desc, base3, n); - return X86EMUL_CONTINUE; -} -#endif - -static int rsm_enter_protected_mode(struct x86_emulate_ctxt *ctxt, - u64 cr0, u64 cr3, u64 cr4) -{ - int bad; - u64 pcid; - - /* In order to later set CR4.PCIDE, CR3[11:0] must be zero. */ - pcid = 0; - if (cr4 & X86_CR4_PCIDE) { - pcid = cr3 & 0xfff; - cr3 &= ~0xfff; - } - - bad = ctxt->ops->set_cr(ctxt, 3, cr3); - if (bad) - return X86EMUL_UNHANDLEABLE; - - /* - * First enable PAE, long mode needs it before CR0.PG = 1 is set. - * Then enable protected mode. However, PCID cannot be enabled - * if EFER.LMA=0, so set it separately. - */ - bad = ctxt->ops->set_cr(ctxt, 4, cr4 & ~X86_CR4_PCIDE); - if (bad) - return X86EMUL_UNHANDLEABLE; - - bad = ctxt->ops->set_cr(ctxt, 0, cr0); - if (bad) - return X86EMUL_UNHANDLEABLE; - - if (cr4 & X86_CR4_PCIDE) { - bad = ctxt->ops->set_cr(ctxt, 4, cr4); - if (bad) - return X86EMUL_UNHANDLEABLE; - if (pcid) { - bad = ctxt->ops->set_cr(ctxt, 3, cr3 | pcid); - if (bad) - return X86EMUL_UNHANDLEABLE; - } - - } - - return X86EMUL_CONTINUE; -} - -static int rsm_load_state_32(struct x86_emulate_ctxt *ctxt, - const char *smstate) -{ - struct desc_struct desc; - struct desc_ptr dt; - u16 selector; - u32 val, cr0, cr3, cr4; - int i; - - cr0 = GET_SMSTATE(u32, smstate, 0x7ffc); - cr3 = GET_SMSTATE(u32, smstate, 0x7ff8); - ctxt->eflags = GET_SMSTATE(u32, smstate, 0x7ff4) | X86_EFLAGS_FIXED; - ctxt->_eip = GET_SMSTATE(u32, smstate, 0x7ff0); - - for (i = 0; i < 8; i++) - *reg_write(ctxt, i) = GET_SMSTATE(u32, smstate, 0x7fd0 + i * 4); - - val = GET_SMSTATE(u32, smstate, 0x7fcc); - - if (ctxt->ops->set_dr(ctxt, 6, val)) - return X86EMUL_UNHANDLEABLE; - - val = GET_SMSTATE(u32, smstate, 0x7fc8); - - if (ctxt->ops->set_dr(ctxt, 7, val)) - return X86EMUL_UNHANDLEABLE; - - selector = GET_SMSTATE(u32, smstate, 0x7fc4); - set_desc_base(&desc, GET_SMSTATE(u32, smstate, 0x7f64)); - set_desc_limit(&desc, GET_SMSTATE(u32, smstate, 0x7f60)); - rsm_set_desc_flags(&desc, GET_SMSTATE(u32, smstate, 0x7f5c)); - ctxt->ops->set_segment(ctxt, selector, &desc, 0, VCPU_SREG_TR); - - selector = GET_SMSTATE(u32, smstate, 0x7fc0); - set_desc_base(&desc, GET_SMSTATE(u32, smstate, 0x7f80)); - set_desc_limit(&desc, GET_SMSTATE(u32, smstate, 0x7f7c)); - rsm_set_desc_flags(&desc, GET_SMSTATE(u32, smstate, 0x7f78)); - ctxt->ops->set_segment(ctxt, selector, &desc, 0, VCPU_SREG_LDTR); - - dt.address = GET_SMSTATE(u32, smstate, 0x7f74); - dt.size = GET_SMSTATE(u32, smstate, 0x7f70); - ctxt->ops->set_gdt(ctxt, &dt); - - dt.address = GET_SMSTATE(u32, smstate, 0x7f58); - dt.size = GET_SMSTATE(u32, smstate, 0x7f54); - ctxt->ops->set_idt(ctxt, &dt); - - for (i = 0; i < 6; i++) { - int r = rsm_load_seg_32(ctxt, smstate, i); - if (r != X86EMUL_CONTINUE) - return r; - } - - cr4 = GET_SMSTATE(u32, smstate, 0x7f14); - - ctxt->ops->set_smbase(ctxt, GET_SMSTATE(u32, smstate, 0x7ef8)); - - return rsm_enter_protected_mode(ctxt, cr0, cr3, cr4); -} - -#ifdef CONFIG_X86_64 -static int rsm_load_state_64(struct x86_emulate_ctxt *ctxt, - const char *smstate) -{ - struct desc_struct desc; - struct desc_ptr dt; - u64 val, cr0, cr3, cr4; - u32 base3; - u16 selector; - int i, r; - - for (i = 0; i < 16; i++) - *reg_write(ctxt, i) = GET_SMSTATE(u64, smstate, 0x7ff8 - i * 8); - - ctxt->_eip = GET_SMSTATE(u64, smstate, 0x7f78); - ctxt->eflags = GET_SMSTATE(u32, smstate, 0x7f70) | X86_EFLAGS_FIXED; - - val = GET_SMSTATE(u64, smstate, 0x7f68); - - if (ctxt->ops->set_dr(ctxt, 6, val)) - return X86EMUL_UNHANDLEABLE; - - val = GET_SMSTATE(u64, smstate, 0x7f60); - - if (ctxt->ops->set_dr(ctxt, 7, val)) - return X86EMUL_UNHANDLEABLE; - - cr0 = GET_SMSTATE(u64, smstate, 0x7f58); - cr3 = GET_SMSTATE(u64, smstate, 0x7f50); - cr4 = GET_SMSTATE(u64, smstate, 0x7f48); - ctxt->ops->set_smbase(ctxt, GET_SMSTATE(u32, smstate, 0x7f00)); - val = GET_SMSTATE(u64, smstate, 0x7ed0); - - if (ctxt->ops->set_msr(ctxt, MSR_EFER, val & ~EFER_LMA)) - return X86EMUL_UNHANDLEABLE; - - selector = GET_SMSTATE(u32, smstate, 0x7e90); - rsm_set_desc_flags(&desc, GET_SMSTATE(u32, smstate, 0x7e92) << 8); - set_desc_limit(&desc, GET_SMSTATE(u32, smstate, 0x7e94)); - set_desc_base(&desc, GET_SMSTATE(u32, smstate, 0x7e98)); - base3 = GET_SMSTATE(u32, smstate, 0x7e9c); - ctxt->ops->set_segment(ctxt, selector, &desc, base3, VCPU_SREG_TR); - - dt.size = GET_SMSTATE(u32, smstate, 0x7e84); - dt.address = GET_SMSTATE(u64, smstate, 0x7e88); - ctxt->ops->set_idt(ctxt, &dt); - - selector = GET_SMSTATE(u32, smstate, 0x7e70); - rsm_set_desc_flags(&desc, GET_SMSTATE(u32, smstate, 0x7e72) << 8); - set_desc_limit(&desc, GET_SMSTATE(u32, smstate, 0x7e74)); - set_desc_base(&desc, GET_SMSTATE(u32, smstate, 0x7e78)); - base3 = GET_SMSTATE(u32, smstate, 0x7e7c); - ctxt->ops->set_segment(ctxt, selector, &desc, base3, VCPU_SREG_LDTR); - - dt.size = GET_SMSTATE(u32, smstate, 0x7e64); - dt.address = GET_SMSTATE(u64, smstate, 0x7e68); - ctxt->ops->set_gdt(ctxt, &dt); - - r = rsm_enter_protected_mode(ctxt, cr0, cr3, cr4); - if (r != X86EMUL_CONTINUE) - return r; - - for (i = 0; i < 6; i++) { - r = rsm_load_seg_64(ctxt, smstate, i); - if (r != X86EMUL_CONTINUE) - return r; - } - - return X86EMUL_CONTINUE; -} -#endif - static int em_rsm(struct x86_emulate_ctxt *ctxt) { - unsigned long cr0, cr4, efer; - char buf[512]; - u64 smbase; - int ret; - if ((ctxt->ops->get_hflags(ctxt) & X86EMUL_SMM_MASK) == 0) return emulate_ud(ctxt); - smbase = ctxt->ops->get_smbase(ctxt); - - ret = ctxt->ops->read_phys(ctxt, smbase + 0xfe00, buf, sizeof(buf)); - if (ret != X86EMUL_CONTINUE) - return X86EMUL_UNHANDLEABLE; - - if ((ctxt->ops->get_hflags(ctxt) & X86EMUL_SMM_INSIDE_NMI_MASK) == 0) - ctxt->ops->set_nmi_mask(ctxt, false); - - ctxt->ops->exiting_smm(ctxt); - - /* - * Get back to real mode, to prepare a safe state in which to load - * CR0/CR3/CR4/EFER. It's all a bit more complicated if the vCPU - * supports long mode. - */ - if (emulator_has_longmode(ctxt)) { - struct desc_struct cs_desc; - - /* Zero CR4.PCIDE before CR0.PG. */ - cr4 = ctxt->ops->get_cr(ctxt, 4); - if (cr4 & X86_CR4_PCIDE) - ctxt->ops->set_cr(ctxt, 4, cr4 & ~X86_CR4_PCIDE); - - /* A 32-bit code segment is required to clear EFER.LMA. */ - memset(&cs_desc, 0, sizeof(cs_desc)); - cs_desc.type = 0xb; - cs_desc.s = cs_desc.g = cs_desc.p = 1; - ctxt->ops->set_segment(ctxt, 0, &cs_desc, 0, VCPU_SREG_CS); - } - - /* For the 64-bit case, this will clear EFER.LMA. */ - cr0 = ctxt->ops->get_cr(ctxt, 0); - if (cr0 & X86_CR0_PE) - ctxt->ops->set_cr(ctxt, 0, cr0 & ~(X86_CR0_PG | X86_CR0_PE)); - - if (emulator_has_longmode(ctxt)) { - /* Clear CR4.PAE before clearing EFER.LME. */ - cr4 = ctxt->ops->get_cr(ctxt, 4); - if (cr4 & X86_CR4_PAE) - ctxt->ops->set_cr(ctxt, 4, cr4 & ~X86_CR4_PAE); - - /* And finally go back to 32-bit mode. */ - efer = 0; - ctxt->ops->set_msr(ctxt, MSR_EFER, efer); - } - - /* - * Give leave_smm() a chance to make ISA-specific changes to the vCPU - * state (e.g. enter guest mode) before loading state from the SMM - * state-save area. - */ - if (ctxt->ops->leave_smm(ctxt, buf)) - goto emulate_shutdown; - -#ifdef CONFIG_X86_64 - if (emulator_has_longmode(ctxt)) - ret = rsm_load_state_64(ctxt, buf); - else -#endif - ret = rsm_load_state_32(ctxt, buf); - - if (ret != X86EMUL_CONTINUE) - goto emulate_shutdown; + if (ctxt->ops->leave_smm(ctxt)) + ctxt->ops->triple_fault(ctxt); - /* - * Note, the ctxt->ops callbacks are responsible for handling side - * effects when writing MSRs and CRs, e.g. MMU context resets, CPUID - * runtime updates, etc... If that changes, e.g. this flow is moved - * out of the emulator to make it look more like enter_smm(), then - * those side effects need to be explicitly handled for both success - * and shutdown. - */ return emulator_recalc_and_set_mode(ctxt); - -emulate_shutdown: - ctxt->ops->triple_fault(ctxt); - return X86EMUL_CONTINUE; } static void |