aboutsummaryrefslogtreecommitdiffstats
path: root/arch/x86/kvm/emulate.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/x86/kvm/emulate.c')
-rw-r--r--arch/x86/kvm/emulate.c67
1 files changed, 62 insertions, 5 deletions
diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
index 2fe9912aeed7..5560ac478135 100644
--- a/arch/x86/kvm/emulate.c
+++ b/arch/x86/kvm/emulate.c
@@ -22,6 +22,7 @@
#include "kvm_cache_regs.h"
#include <asm/kvm_emulate.h>
#include <linux/stringify.h>
+#include <asm/fpu/api.h>
#include <asm/debugreg.h>
#include <asm/nospec-branch.h>
@@ -1057,8 +1058,23 @@ static void fetch_register_operand(struct operand *op)
}
}
+static void emulator_get_fpu(void)
+{
+ fpregs_lock();
+
+ fpregs_assert_state_consistent();
+ if (test_thread_flag(TIF_NEED_FPU_LOAD))
+ switch_fpu_return();
+}
+
+static void emulator_put_fpu(void)
+{
+ fpregs_unlock();
+}
+
static void read_sse_reg(struct x86_emulate_ctxt *ctxt, sse128_t *data, int reg)
{
+ emulator_get_fpu();
switch (reg) {
case 0: asm("movdqa %%xmm0, %0" : "=m"(*data)); break;
case 1: asm("movdqa %%xmm1, %0" : "=m"(*data)); break;
@@ -1080,11 +1096,13 @@ static void read_sse_reg(struct x86_emulate_ctxt *ctxt, sse128_t *data, int reg)
#endif
default: BUG();
}
+ emulator_put_fpu();
}
static void write_sse_reg(struct x86_emulate_ctxt *ctxt, sse128_t *data,
int reg)
{
+ emulator_get_fpu();
switch (reg) {
case 0: asm("movdqa %0, %%xmm0" : : "m"(*data)); break;
case 1: asm("movdqa %0, %%xmm1" : : "m"(*data)); break;
@@ -1106,10 +1124,12 @@ static void write_sse_reg(struct x86_emulate_ctxt *ctxt, sse128_t *data,
#endif
default: BUG();
}
+ emulator_put_fpu();
}
static void read_mmx_reg(struct x86_emulate_ctxt *ctxt, u64 *data, int reg)
{
+ emulator_get_fpu();
switch (reg) {
case 0: asm("movq %%mm0, %0" : "=m"(*data)); break;
case 1: asm("movq %%mm1, %0" : "=m"(*data)); break;
@@ -1121,10 +1141,12 @@ static void read_mmx_reg(struct x86_emulate_ctxt *ctxt, u64 *data, int reg)
case 7: asm("movq %%mm7, %0" : "=m"(*data)); break;
default: BUG();
}
+ emulator_put_fpu();
}
static void write_mmx_reg(struct x86_emulate_ctxt *ctxt, u64 *data, int reg)
{
+ emulator_get_fpu();
switch (reg) {
case 0: asm("movq %0, %%mm0" : : "m"(*data)); break;
case 1: asm("movq %0, %%mm1" : : "m"(*data)); break;
@@ -1136,6 +1158,7 @@ static void write_mmx_reg(struct x86_emulate_ctxt *ctxt, u64 *data, int reg)
case 7: asm("movq %0, %%mm7" : : "m"(*data)); break;
default: BUG();
}
+ emulator_put_fpu();
}
static int em_fninit(struct x86_emulate_ctxt *ctxt)
@@ -1143,7 +1166,9 @@ static int em_fninit(struct x86_emulate_ctxt *ctxt)
if (ctxt->ops->get_cr(ctxt, 0) & (X86_CR0_TS | X86_CR0_EM))
return emulate_nm(ctxt);
+ emulator_get_fpu();
asm volatile("fninit");
+ emulator_put_fpu();
return X86EMUL_CONTINUE;
}
@@ -1154,7 +1179,9 @@ static int em_fnstcw(struct x86_emulate_ctxt *ctxt)
if (ctxt->ops->get_cr(ctxt, 0) & (X86_CR0_TS | X86_CR0_EM))
return emulate_nm(ctxt);
+ emulator_get_fpu();
asm volatile("fnstcw %0": "+m"(fcw));
+ emulator_put_fpu();
ctxt->dst.val = fcw;
@@ -1168,7 +1195,9 @@ static int em_fnstsw(struct x86_emulate_ctxt *ctxt)
if (ctxt->ops->get_cr(ctxt, 0) & (X86_CR0_TS | X86_CR0_EM))
return emulate_nm(ctxt);
+ emulator_get_fpu();
asm volatile("fnstsw %0": "+m"(fsw));
+ emulator_put_fpu();
ctxt->dst.val = fsw;
@@ -4076,8 +4105,12 @@ static int em_fxsave(struct x86_emulate_ctxt *ctxt)
if (rc != X86EMUL_CONTINUE)
return rc;
+ emulator_get_fpu();
+
rc = asm_safe("fxsave %[fx]", , [fx] "+m"(fx_state));
+ emulator_put_fpu();
+
if (rc != X86EMUL_CONTINUE)
return rc;
@@ -4120,6 +4153,8 @@ static int em_fxrstor(struct x86_emulate_ctxt *ctxt)
if (rc != X86EMUL_CONTINUE)
return rc;
+ emulator_get_fpu();
+
if (size < __fxstate_size(16)) {
rc = fxregs_fixup(&fx_state, size);
if (rc != X86EMUL_CONTINUE)
@@ -4135,6 +4170,8 @@ static int em_fxrstor(struct x86_emulate_ctxt *ctxt)
rc = asm_safe("fxrstor %[fx]", : [fx] "m"(fx_state));
out:
+ emulator_put_fpu();
+
return rc;
}
@@ -5121,6 +5158,7 @@ int x86_decode_insn(struct x86_emulate_ctxt *ctxt, void *insn, int insn_len)
ctxt->fetch.ptr = ctxt->fetch.data;
ctxt->fetch.end = ctxt->fetch.data + insn_len;
ctxt->opcode_len = 1;
+ ctxt->intercept = x86_intercept_none;
if (insn_len > 0)
memcpy(ctxt->fetch.data, insn, insn_len);
else {
@@ -5173,16 +5211,28 @@ int x86_decode_insn(struct x86_emulate_ctxt *ctxt, void *insn, int insn_len)
ctxt->ad_bytes = def_ad_bytes ^ 6;
break;
case 0x26: /* ES override */
+ has_seg_override = true;
+ ctxt->seg_override = VCPU_SREG_ES;
+ break;
case 0x2e: /* CS override */
+ has_seg_override = true;
+ ctxt->seg_override = VCPU_SREG_CS;
+ break;
case 0x36: /* SS override */
+ has_seg_override = true;
+ ctxt->seg_override = VCPU_SREG_SS;
+ break;
case 0x3e: /* DS override */
has_seg_override = true;
- ctxt->seg_override = (ctxt->b >> 3) & 3;
+ ctxt->seg_override = VCPU_SREG_DS;
break;
case 0x64: /* FS override */
+ has_seg_override = true;
+ ctxt->seg_override = VCPU_SREG_FS;
+ break;
case 0x65: /* GS override */
has_seg_override = true;
- ctxt->seg_override = ctxt->b & 7;
+ ctxt->seg_override = VCPU_SREG_GS;
break;
case 0x40 ... 0x4f: /* REX */
if (mode != X86EMUL_MODE_PROT64)
@@ -5266,10 +5316,15 @@ done_prefixes:
}
break;
case Escape:
- if (ctxt->modrm > 0xbf)
- opcode = opcode.u.esc->high[ctxt->modrm - 0xc0];
- else
+ if (ctxt->modrm > 0xbf) {
+ size_t size = ARRAY_SIZE(opcode.u.esc->high);
+ u32 index = array_index_nospec(
+ ctxt->modrm - 0xc0, size);
+
+ opcode = opcode.u.esc->high[index];
+ } else {
opcode = opcode.u.esc->op[(ctxt->modrm >> 3) & 7];
+ }
break;
case InstrDual:
if ((ctxt->modrm >> 6) == 3)
@@ -5411,7 +5466,9 @@ static int flush_pending_x87_faults(struct x86_emulate_ctxt *ctxt)
{
int rc;
+ emulator_get_fpu();
rc = asm_safe("fwait");
+ emulator_put_fpu();
if (unlikely(rc != X86EMUL_CONTINUE))
return emulate_exception(ctxt, MF_VECTOR, 0, false);
generated by cgit 1.2.3-korg (git 2.39.0) at 2024-05-04 09:40:08 +0000