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Diffstat (limited to 'arch/x86/kvm/emulate.c')
-rw-r--r--arch/x86/kvm/emulate.c162
1 files changed, 66 insertions, 96 deletions
diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
index 2673cd5c46cb..60986f67c35a 100644
--- a/arch/x86/kvm/emulate.c
+++ b/arch/x86/kvm/emulate.c
@@ -651,9 +651,10 @@ static inline u8 ctxt_virt_addr_bits(struct x86_emulate_ctxt *ctxt)
}
static inline bool emul_is_noncanonical_address(u64 la,
- struct x86_emulate_ctxt *ctxt)
+ struct x86_emulate_ctxt *ctxt,
+ unsigned int flags)
{
- return !__is_canonical_address(la, ctxt_virt_addr_bits(ctxt));
+ return !ctxt->ops->is_canonical_addr(ctxt, la, flags);
}
/*
@@ -687,8 +688,8 @@ static unsigned insn_alignment(struct x86_emulate_ctxt *ctxt, unsigned size)
static __always_inline int __linearize(struct x86_emulate_ctxt *ctxt,
struct segmented_address addr,
unsigned *max_size, unsigned size,
- bool write, bool fetch,
- enum x86emul_mode mode, ulong *linear)
+ enum x86emul_mode mode, ulong *linear,
+ unsigned int flags)
{
struct desc_struct desc;
bool usable;
@@ -701,7 +702,7 @@ static __always_inline int __linearize(struct x86_emulate_ctxt *ctxt,
*max_size = 0;
switch (mode) {
case X86EMUL_MODE_PROT64:
- *linear = la;
+ *linear = la = ctxt->ops->get_untagged_addr(ctxt, la, flags);
va_bits = ctxt_virt_addr_bits(ctxt);
if (!__is_canonical_address(la, va_bits))
goto bad;
@@ -717,11 +718,11 @@ static __always_inline int __linearize(struct x86_emulate_ctxt *ctxt,
if (!usable)
goto bad;
/* code segment in protected mode or read-only data segment */
- if ((((ctxt->mode != X86EMUL_MODE_REAL) && (desc.type & 8))
- || !(desc.type & 2)) && write)
+ if ((((ctxt->mode != X86EMUL_MODE_REAL) && (desc.type & 8)) || !(desc.type & 2)) &&
+ (flags & X86EMUL_F_WRITE))
goto bad;
/* unreadable code segment */
- if (!fetch && (desc.type & 8) && !(desc.type & 2))
+ if (!(flags & X86EMUL_F_FETCH) && (desc.type & 8) && !(desc.type & 2))
goto bad;
lim = desc_limit_scaled(&desc);
if (!(desc.type & 8) && (desc.type & 4)) {
@@ -757,8 +758,8 @@ static int linearize(struct x86_emulate_ctxt *ctxt,
ulong *linear)
{
unsigned max_size;
- return __linearize(ctxt, addr, &max_size, size, write, false,
- ctxt->mode, linear);
+ return __linearize(ctxt, addr, &max_size, size, ctxt->mode, linear,
+ write ? X86EMUL_F_WRITE : 0);
}
static inline int assign_eip(struct x86_emulate_ctxt *ctxt, ulong dst)
@@ -771,7 +772,8 @@ static inline int assign_eip(struct x86_emulate_ctxt *ctxt, ulong dst)
if (ctxt->op_bytes != sizeof(unsigned long))
addr.ea = dst & ((1UL << (ctxt->op_bytes << 3)) - 1);
- rc = __linearize(ctxt, addr, &max_size, 1, false, true, ctxt->mode, &linear);
+ rc = __linearize(ctxt, addr, &max_size, 1, ctxt->mode, &linear,
+ X86EMUL_F_FETCH);
if (rc == X86EMUL_CONTINUE)
ctxt->_eip = addr.ea;
return rc;
@@ -907,8 +909,8 @@ static int __do_insn_fetch_bytes(struct x86_emulate_ctxt *ctxt, int op_size)
* boundary check itself. Instead, we use max_size to check
* against op_size.
*/
- rc = __linearize(ctxt, addr, &max_size, 0, false, true, ctxt->mode,
- &linear);
+ rc = __linearize(ctxt, addr, &max_size, 0, ctxt->mode, &linear,
+ X86EMUL_F_FETCH);
if (unlikely(rc != X86EMUL_CONTINUE))
return rc;
@@ -1068,7 +1070,7 @@ static __always_inline u8 test_cc(unsigned int condition, unsigned long flags)
flags = (flags & EFLAGS_MASK) | X86_EFLAGS_IF;
asm("push %[flags]; popf; " CALL_NOSPEC
- : "=a"(rc) : [thunk_target]"r"(fop), [flags]"r"(flags));
+ : "=a"(rc), ASM_CALL_CONSTRAINT : [thunk_target]"r"(fop), [flags]"r"(flags));
return rc;
}
@@ -1732,7 +1734,8 @@ static int __load_segment_descriptor(struct x86_emulate_ctxt *ctxt,
if (ret != X86EMUL_CONTINUE)
return ret;
if (emul_is_noncanonical_address(get_desc_base(&seg_desc) |
- ((u64)base3 << 32), ctxt))
+ ((u64)base3 << 32), ctxt,
+ X86EMUL_F_DT_LOAD))
return emulate_gp(ctxt, err_code);
}
@@ -1819,22 +1822,22 @@ static int writeback(struct x86_emulate_ctxt *ctxt, struct operand *op)
return X86EMUL_CONTINUE;
}
-static int push(struct x86_emulate_ctxt *ctxt, void *data, int bytes)
+static int emulate_push(struct x86_emulate_ctxt *ctxt, const void *data, int len)
{
struct segmented_address addr;
- rsp_increment(ctxt, -bytes);
+ rsp_increment(ctxt, -len);
addr.ea = reg_read(ctxt, VCPU_REGS_RSP) & stack_mask(ctxt);
addr.seg = VCPU_SREG_SS;
- return segmented_write(ctxt, addr, data, bytes);
+ return segmented_write(ctxt, addr, data, len);
}
static int em_push(struct x86_emulate_ctxt *ctxt)
{
/* Disable writeback. */
ctxt->dst.type = OP_NONE;
- return push(ctxt, &ctxt->src.val, ctxt->op_bytes);
+ return emulate_push(ctxt, &ctxt->src.val, ctxt->op_bytes);
}
static int emulate_pop(struct x86_emulate_ctxt *ctxt,
@@ -1862,7 +1865,8 @@ static int emulate_popf(struct x86_emulate_ctxt *ctxt,
void *dest, int len)
{
int rc;
- unsigned long val, change_mask;
+ unsigned long val = 0;
+ unsigned long change_mask;
int iopl = (ctxt->eflags & X86_EFLAGS_IOPL) >> X86_EFLAGS_IOPL_BIT;
int cpl = ctxt->ops->cpl(ctxt);
@@ -1919,7 +1923,7 @@ static int em_enter(struct x86_emulate_ctxt *ctxt)
return X86EMUL_UNHANDLEABLE;
rbp = reg_read(ctxt, VCPU_REGS_RBP);
- rc = push(ctxt, &rbp, stack_size(ctxt));
+ rc = emulate_push(ctxt, &rbp, stack_size(ctxt));
if (rc != X86EMUL_CONTINUE)
return rc;
assign_masked(reg_rmw(ctxt, VCPU_REGS_RBP), reg_read(ctxt, VCPU_REGS_RSP),
@@ -1953,7 +1957,7 @@ static int em_push_sreg(struct x86_emulate_ctxt *ctxt)
static int em_pop_sreg(struct x86_emulate_ctxt *ctxt)
{
int seg = ctxt->src2.val;
- unsigned long selector;
+ unsigned long selector = 0;
int rc;
rc = emulate_pop(ctxt, &selector, 2);
@@ -1999,7 +2003,7 @@ static int em_popa(struct x86_emulate_ctxt *ctxt)
{
int rc = X86EMUL_CONTINUE;
int reg = VCPU_REGS_RDI;
- u32 val;
+ u32 val = 0;
while (reg >= VCPU_REGS_RAX) {
if (reg == VCPU_REGS_RSP) {
@@ -2228,7 +2232,7 @@ static int em_cmpxchg8b(struct x86_emulate_ctxt *ctxt)
static int em_ret(struct x86_emulate_ctxt *ctxt)
{
int rc;
- unsigned long eip;
+ unsigned long eip = 0;
rc = emulate_pop(ctxt, &eip, ctxt->op_bytes);
if (rc != X86EMUL_CONTINUE)
@@ -2240,7 +2244,8 @@ static int em_ret(struct x86_emulate_ctxt *ctxt)
static int em_ret_far(struct x86_emulate_ctxt *ctxt)
{
int rc;
- unsigned long eip, cs;
+ unsigned long eip = 0;
+ unsigned long cs = 0;
int cpl = ctxt->ops->cpl(ctxt);
struct desc_struct new_desc;
@@ -2351,50 +2356,6 @@ setup_syscalls_segments(struct desc_struct *cs, struct desc_struct *ss)
ss->avl = 0;
}
-static bool vendor_intel(struct x86_emulate_ctxt *ctxt)
-{
- u32 eax, ebx, ecx, edx;
-
- eax = ecx = 0;
- ctxt->ops->get_cpuid(ctxt, &eax, &ebx, &ecx, &edx, true);
- return is_guest_vendor_intel(ebx, ecx, edx);
-}
-
-static bool em_syscall_is_enabled(struct x86_emulate_ctxt *ctxt)
-{
- const struct x86_emulate_ops *ops = ctxt->ops;
- u32 eax, ebx, ecx, edx;
-
- /*
- * syscall should always be enabled in longmode - so only become
- * vendor specific (cpuid) if other modes are active...
- */
- if (ctxt->mode == X86EMUL_MODE_PROT64)
- return true;
-
- eax = 0x00000000;
- ecx = 0x00000000;
- ops->get_cpuid(ctxt, &eax, &ebx, &ecx, &edx, true);
- /*
- * remark: Intel CPUs only support "syscall" in 64bit longmode. Also a
- * 64bit guest with a 32bit compat-app running will #UD !! While this
- * behaviour can be fixed (by emulating) into AMD response - CPUs of
- * AMD can't behave like Intel.
- */
- if (is_guest_vendor_intel(ebx, ecx, edx))
- return false;
-
- if (is_guest_vendor_amd(ebx, ecx, edx) ||
- is_guest_vendor_hygon(ebx, ecx, edx))
- return true;
-
- /*
- * default: (not Intel, not AMD, not Hygon), apply Intel's
- * stricter rules...
- */
- return false;
-}
-
static int em_syscall(struct x86_emulate_ctxt *ctxt)
{
const struct x86_emulate_ops *ops = ctxt->ops;
@@ -2408,7 +2369,15 @@ static int em_syscall(struct x86_emulate_ctxt *ctxt)
ctxt->mode == X86EMUL_MODE_VM86)
return emulate_ud(ctxt);
- if (!(em_syscall_is_enabled(ctxt)))
+ /*
+ * Intel compatible CPUs only support SYSCALL in 64-bit mode, whereas
+ * AMD allows SYSCALL in any flavor of protected mode. Note, it's
+ * infeasible to emulate Intel behavior when running on AMD hardware,
+ * as SYSCALL won't fault in the "wrong" mode, i.e. there is no #UD
+ * for KVM to trap-and-emulate, unlike emulating AMD on Intel.
+ */
+ if (ctxt->mode != X86EMUL_MODE_PROT64 &&
+ ctxt->ops->guest_cpuid_is_intel_compatible(ctxt))
return emulate_ud(ctxt);
ops->get_msr(ctxt, MSR_EFER, &efer);
@@ -2468,11 +2437,11 @@ static int em_sysenter(struct x86_emulate_ctxt *ctxt)
return emulate_gp(ctxt, 0);
/*
- * Not recognized on AMD in compat mode (but is recognized in legacy
- * mode).
+ * Intel's architecture allows SYSENTER in compatibility mode, but AMD
+ * does not. Note, AMD does allow SYSENTER in legacy protected mode.
*/
- if ((ctxt->mode != X86EMUL_MODE_PROT64) && (efer & EFER_LMA)
- && !vendor_intel(ctxt))
+ if ((ctxt->mode != X86EMUL_MODE_PROT64) && (efer & EFER_LMA) &&
+ !ctxt->ops->guest_cpuid_is_intel_compatible(ctxt))
return emulate_ud(ctxt);
/* sysenter/sysexit have not been tested in 64bit mode. */
@@ -2549,8 +2518,8 @@ static int em_sysexit(struct x86_emulate_ctxt *ctxt)
ss_sel = cs_sel + 8;
cs.d = 0;
cs.l = 1;
- if (emul_is_noncanonical_address(rcx, ctxt) ||
- emul_is_noncanonical_address(rdx, ctxt))
+ if (emul_is_noncanonical_address(rcx, ctxt, 0) ||
+ emul_is_noncanonical_address(rdx, ctxt, 0))
return emulate_gp(ctxt, 0);
break;
}
@@ -2644,7 +2613,14 @@ static void string_registers_quirk(struct x86_emulate_ctxt *ctxt)
* manner when ECX is zero due to REP-string optimizations.
*/
#ifdef CONFIG_X86_64
- if (ctxt->ad_bytes != 4 || !vendor_intel(ctxt))
+ u32 eax, ebx, ecx, edx;
+
+ if (ctxt->ad_bytes != 4)
+ return;
+
+ eax = ecx = 0;
+ ctxt->ops->get_cpuid(ctxt, &eax, &ebx, &ecx, &edx, true);
+ if (!is_guest_vendor_intel(ebx, ecx, edx))
return;
*reg_write(ctxt, VCPU_REGS_RCX) = 0;
@@ -3010,7 +2986,7 @@ static int emulator_do_task_switch(struct x86_emulate_ctxt *ctxt,
ret = em_push(ctxt);
}
- ops->get_dr(ctxt, 7, &dr7);
+ dr7 = ops->get_dr(ctxt, 7);
ops->set_dr(ctxt, 7, dr7 & ~(DR_LOCAL_ENABLE_MASK | DR_LOCAL_SLOWDOWN));
return ret;
@@ -3183,7 +3159,7 @@ fail:
static int em_ret_near_imm(struct x86_emulate_ctxt *ctxt)
{
int rc;
- unsigned long eip;
+ unsigned long eip = 0;
rc = emulate_pop(ctxt, &eip, ctxt->op_bytes);
if (rc != X86EMUL_CONTINUE)
@@ -3439,8 +3415,10 @@ static int em_invlpg(struct x86_emulate_ctxt *ctxt)
{
int rc;
ulong linear;
+ unsigned int max_size;
- rc = linearize(ctxt, ctxt->src.addr.mem, 1, false, &linear);
+ rc = __linearize(ctxt, ctxt->src.addr.mem, &max_size, 1, ctxt->mode,
+ &linear, X86EMUL_F_INVLPG);
if (rc == X86EMUL_CONTINUE)
ctxt->ops->invlpg(ctxt, linear);
/* Disable writeback. */
@@ -3518,7 +3496,8 @@ static int em_lgdt_lidt(struct x86_emulate_ctxt *ctxt, bool lgdt)
if (rc != X86EMUL_CONTINUE)
return rc;
if (ctxt->mode == X86EMUL_MODE_PROT64 &&
- emul_is_noncanonical_address(desc_ptr.address, ctxt))
+ emul_is_noncanonical_address(desc_ptr.address, ctxt,
+ X86EMUL_F_DT_LOAD))
return emulate_gp(ctxt, 0);
if (lgdt)
ctxt->ops->set_gdt(ctxt, &desc_ptr);
@@ -3863,15 +3842,6 @@ static int check_cr_access(struct x86_emulate_ctxt *ctxt)
return X86EMUL_CONTINUE;
}
-static int check_dr7_gd(struct x86_emulate_ctxt *ctxt)
-{
- unsigned long dr7;
-
- ctxt->ops->get_dr(ctxt, 7, &dr7);
-
- return dr7 & DR7_GD;
-}
-
static int check_dr_read(struct x86_emulate_ctxt *ctxt)
{
int dr = ctxt->modrm_reg;
@@ -3884,10 +3854,10 @@ static int check_dr_read(struct x86_emulate_ctxt *ctxt)
if ((cr4 & X86_CR4_DE) && (dr == 4 || dr == 5))
return emulate_ud(ctxt);
- if (check_dr7_gd(ctxt)) {
+ if (ctxt->ops->get_dr(ctxt, 7) & DR7_GD) {
ulong dr6;
- ctxt->ops->get_dr(ctxt, 6, &dr6);
+ dr6 = ctxt->ops->get_dr(ctxt, 6);
dr6 &= ~DR_TRAP_BITS;
dr6 |= DR6_BD | DR6_ACTIVE_LOW;
ctxt->ops->set_dr(ctxt, 6, dr6);
@@ -3959,7 +3929,7 @@ static int check_rdpmc(struct x86_emulate_ctxt *ctxt)
* protected mode.
*/
if ((!(cr4 & X86_CR4_PCE) && ctxt->ops->cpl(ctxt)) ||
- ctxt->ops->check_pmc(ctxt, rcx))
+ ctxt->ops->check_rdpmc_early(ctxt, rcx))
return emulate_gp(ctxt, 0);
return X86EMUL_CONTINUE;
@@ -4502,11 +4472,11 @@ static const struct instr_dual instr_dual_0f_38_f1 = {
};
static const struct gprefix three_byte_0f_38_f0 = {
- ID(0, &instr_dual_0f_38_f0), N, N, N
+ ID(0, &instr_dual_0f_38_f0), ID(0, &instr_dual_0f_38_f0), N, N
};
static const struct gprefix three_byte_0f_38_f1 = {
- ID(0, &instr_dual_0f_38_f1), N, N, N
+ ID(0, &instr_dual_0f_38_f1), ID(0, &instr_dual_0f_38_f1), N, N
};
/*
@@ -5446,7 +5416,7 @@ twobyte_insn:
ctxt->dst.val = ops->get_cr(ctxt, ctxt->modrm_reg);
break;
case 0x21: /* mov from dr to reg */
- ops->get_dr(ctxt, ctxt->modrm_reg, &ctxt->dst.val);
+ ctxt->dst.val = ops->get_dr(ctxt, ctxt->modrm_reg);
break;
case 0x40 ... 0x4f: /* cmov */
if (test_cc(ctxt->b, ctxt->eflags))