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Diffstat (limited to 'arch/x86/kvm/emulate.c')
-rw-r--r--arch/x86/kvm/emulate.c355
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
generated by cgit v1.2.3 (git 2.39.0) at 2024-07-15 07:43:51 +0300