Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
Merge branch 'kvm-updates/3.3' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Fixing a regression with the PMU MSRs when PMU virtualization is
disabled, a guest-internal DoS with the SYSCALL instruction, and a dirty
memory logging race that may cause live migration to fail.
* 'kvm-updates/3.3' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
KVM: do not #GP on perf MSR writes when vPMU is disabled
KVM: x86: fix missing checks in syscall emulation
KVM: x86: extend "struct x86_emulate_ops" with "get_cpuid"
KVM: Fix __set_bit() race in mark_page_dirty() during dirty logging
+113
-1
+16
arch/x86/include/asm/kvm_emulate.h
+16
arch/x86/include/asm/kvm_emulate.h
···
190
190
int (*intercept)(struct x86_emulate_ctxt *ctxt,
191
191
struct x86_instruction_info *info,
192
192
enum x86_intercept_stage stage);
193
+
194
+
bool (*get_cpuid)(struct x86_emulate_ctxt *ctxt,
195
+
u32 *eax, u32 *ebx, u32 *ecx, u32 *edx);
193
196
};
194
197
195
198
typedef u32 __attribute__((vector_size(16))) sse128_t;
···
300
297
/* any protected mode */
301
298
#define X86EMUL_MODE_PROT (X86EMUL_MODE_PROT16|X86EMUL_MODE_PROT32| \
302
299
X86EMUL_MODE_PROT64)
300
+
301
+
/* CPUID vendors */
302
+
#define X86EMUL_CPUID_VENDOR_AuthenticAMD_ebx 0x68747541
303
+
#define X86EMUL_CPUID_VENDOR_AuthenticAMD_ecx 0x444d4163
304
+
#define X86EMUL_CPUID_VENDOR_AuthenticAMD_edx 0x69746e65
305
+
306
+
#define X86EMUL_CPUID_VENDOR_AMDisbetterI_ebx 0x69444d41
307
+
#define X86EMUL_CPUID_VENDOR_AMDisbetterI_ecx 0x21726574
308
+
#define X86EMUL_CPUID_VENDOR_AMDisbetterI_edx 0x74656273
309
+
310
+
#define X86EMUL_CPUID_VENDOR_GenuineIntel_ebx 0x756e6547
311
+
#define X86EMUL_CPUID_VENDOR_GenuineIntel_ecx 0x6c65746e
312
+
#define X86EMUL_CPUID_VENDOR_GenuineIntel_edx 0x49656e69
303
313
304
314
enum x86_intercept_stage {
305
315
X86_ICTP_NONE = 0, /* Allow zero-init to not match anything */
+51
arch/x86/kvm/emulate.c
+51
arch/x86/kvm/emulate.c
···
1891
1891
ss->p = 1;
1892
1892
}
1893
1893
1894
+
static bool em_syscall_is_enabled(struct x86_emulate_ctxt *ctxt)
1895
+
{
1896
+
struct x86_emulate_ops *ops = ctxt->ops;
1897
+
u32 eax, ebx, ecx, edx;
1898
+
1899
+
/*
1900
+
* syscall should always be enabled in longmode - so only become
1901
+
* vendor specific (cpuid) if other modes are active...
1902
+
*/
1903
+
if (ctxt->mode == X86EMUL_MODE_PROT64)
1904
+
return true;
1905
+
1906
+
eax = 0x00000000;
1907
+
ecx = 0x00000000;
1908
+
if (ops->get_cpuid(ctxt, &eax, &ebx, &ecx, &edx)) {
1909
+
/*
1910
+
* Intel ("GenuineIntel")
1911
+
* remark: Intel CPUs only support "syscall" in 64bit
1912
+
* longmode. Also an 64bit guest with a
1913
+
* 32bit compat-app running will #UD !! While this
1914
+
* behaviour can be fixed (by emulating) into AMD
1915
+
* response - CPUs of AMD can't behave like Intel.
1916
+
*/
1917
+
if (ebx == X86EMUL_CPUID_VENDOR_GenuineIntel_ebx &&
1918
+
ecx == X86EMUL_CPUID_VENDOR_GenuineIntel_ecx &&
1919
+
edx == X86EMUL_CPUID_VENDOR_GenuineIntel_edx)
1920
+
return false;
1921
+
1922
+
/* AMD ("AuthenticAMD") */
1923
+
if (ebx == X86EMUL_CPUID_VENDOR_AuthenticAMD_ebx &&
1924
+
ecx == X86EMUL_CPUID_VENDOR_AuthenticAMD_ecx &&
1925
+
edx == X86EMUL_CPUID_VENDOR_AuthenticAMD_edx)
1926
+
return true;
1927
+
1928
+
/* AMD ("AMDisbetter!") */
1929
+
if (ebx == X86EMUL_CPUID_VENDOR_AMDisbetterI_ebx &&
1930
+
ecx == X86EMUL_CPUID_VENDOR_AMDisbetterI_ecx &&
1931
+
edx == X86EMUL_CPUID_VENDOR_AMDisbetterI_edx)
1932
+
return true;
1933
+
}
1934
+
1935
+
/* default: (not Intel, not AMD), apply Intel's stricter rules... */
1936
+
return false;
1937
+
}
1938
+
1894
1939
static int em_syscall(struct x86_emulate_ctxt *ctxt)
1895
1940
{
1896
1941
struct x86_emulate_ops *ops = ctxt->ops;
···
1949
1904
ctxt->mode == X86EMUL_MODE_VM86)
1950
1905
return emulate_ud(ctxt);
1951
1906
1907
+
if (!(em_syscall_is_enabled(ctxt)))
1908
+
return emulate_ud(ctxt);
1909
+
1952
1910
ops->get_msr(ctxt, MSR_EFER, &efer);
1953
1911
setup_syscalls_segments(ctxt, &cs, &ss);
1912
+
1913
+
if (!(efer & EFER_SCE))
1914
+
return emulate_ud(ctxt);
1954
1915
1955
1916
ops->get_msr(ctxt, MSR_STAR, &msr_data);
1956
1917
msr_data >>= 32;
+45
arch/x86/kvm/x86.c
+45
arch/x86/kvm/x86.c
···
1495
1495
1496
1496
int kvm_set_msr_common(struct kvm_vcpu *vcpu, u32 msr, u64 data)
1497
1497
{
1498
+
bool pr = false;
1499
+
1498
1500
switch (msr) {
1499
1501
case MSR_EFER:
1500
1502
return set_efer(vcpu, data);
···
1636
1634
case MSR_K7_PERFCTR3:
1637
1635
pr_unimpl(vcpu, "unimplemented perfctr wrmsr: "
1638
1636
"0x%x data 0x%llx\n", msr, data);
1637
+
break;
1638
+
case MSR_P6_PERFCTR0:
1639
+
case MSR_P6_PERFCTR1:
1640
+
pr = true;
1641
+
case MSR_P6_EVNTSEL0:
1642
+
case MSR_P6_EVNTSEL1:
1643
+
if (kvm_pmu_msr(vcpu, msr))
1644
+
return kvm_pmu_set_msr(vcpu, msr, data);
1645
+
1646
+
if (pr || data != 0)
1647
+
pr_unimpl(vcpu, "disabled perfctr wrmsr: "
1648
+
"0x%x data 0x%llx\n", msr, data);
1639
1649
break;
1640
1650
case MSR_K7_CLK_CTL:
1641
1651
/*
···
1847
1833
case MSR_K8_INT_PENDING_MSG:
1848
1834
case MSR_AMD64_NB_CFG:
1849
1835
case MSR_FAM10H_MMIO_CONF_BASE:
1836
+
data = 0;
1837
+
break;
1838
+
case MSR_P6_PERFCTR0:
1839
+
case MSR_P6_PERFCTR1:
1840
+
case MSR_P6_EVNTSEL0:
1841
+
case MSR_P6_EVNTSEL1:
1842
+
if (kvm_pmu_msr(vcpu, msr))
1843
+
return kvm_pmu_get_msr(vcpu, msr, pdata);
1850
1844
data = 0;
1851
1845
break;
1852
1846
case MSR_IA32_UCODE_REV:
···
4202
4180
return kvm_x86_ops->check_intercept(emul_to_vcpu(ctxt), info, stage);
4203
4181
}
4204
4182
4183
+
static bool emulator_get_cpuid(struct x86_emulate_ctxt *ctxt,
4184
+
u32 *eax, u32 *ebx, u32 *ecx, u32 *edx)
4185
+
{
4186
+
struct kvm_cpuid_entry2 *cpuid = NULL;
4187
+
4188
+
if (eax && ecx)
4189
+
cpuid = kvm_find_cpuid_entry(emul_to_vcpu(ctxt),
4190
+
*eax, *ecx);
4191
+
4192
+
if (cpuid) {
4193
+
*eax = cpuid->eax;
4194
+
*ecx = cpuid->ecx;
4195
+
if (ebx)
4196
+
*ebx = cpuid->ebx;
4197
+
if (edx)
4198
+
*edx = cpuid->edx;
4199
+
return true;
4200
+
}
4201
+
4202
+
return false;
4203
+
}
4204
+
4205
4205
static struct x86_emulate_ops emulate_ops = {
4206
4206
.read_std = kvm_read_guest_virt_system,
4207
4207
.write_std = kvm_write_guest_virt_system,
···
4255
4211
.get_fpu = emulator_get_fpu,
4256
4212
.put_fpu = emulator_put_fpu,
4257
4213
.intercept = emulator_intercept,
4214
+
.get_cpuid = emulator_get_cpuid,
4258
4215
};
4259
4216
4260
4217
static void cache_all_regs(struct kvm_vcpu *vcpu)
+1
-1
virt/kvm/kvm_main.c
+1
-1
virt/kvm/kvm_main.c
···
1543
1543
if (memslot && memslot->dirty_bitmap) {
1544
1544
unsigned long rel_gfn = gfn - memslot->base_gfn;
1545
1545
1546
-
if (!__test_and_set_bit_le(rel_gfn, memslot->dirty_bitmap))
1546
+
if (!test_and_set_bit_le(rel_gfn, memslot->dirty_bitmap))
1547
1547
memslot->nr_dirty_pages++;
1548
1548
}
1549
1549
}