Re: [libvirt] [PATCH 03/10] cpu_x86: Add full support for ecx_in CPUID parameter

This patch makes our CPUID handling code up-to-date with the current specification found in Intel® 64 and IA-32 Architectures Developer's Manual: Vol. 2A http://www.intel.com/content/www/us/en/processors/architectures-software-... Signed-off-by: Jiri Denemark <jdenemar(a)redhat.com&gt; --- src/cpu/cpu_map.xml | 1 - src/cpu/cpu_x86.c | 278 ++++++++++++++++++++++++++++++++++++++++++++++++++-- 2 files changed, 269 insertions(+), 10 deletions(-)

@@ -1862,8 +1862,7 @@ cpuidCall(virCPUx86CPUID *cpuid) { # if __x86_64__ asm("xor %%ebx, %%ebx;" /* clear the other registers as some cpuid */ - "xor %%ecx, %%ecx;" /* functions may use them as additional */ - "xor %%edx, %%edx;" /* arguments */ + "xor %%edx, %%edx;" /* functions may use them as additional arguments */ "cpuid;" : "=a" (cpuid->eax), "=b" (cpuid->ebx), @@ -1877,8 +1876,7 @@ cpuidCall(virCPUx86CPUID *cpuid) */ asm("push %%ebx;" "xor %%ebx, %%ebx;" /* clear the other registers as some cpuid */ - "xor %%ecx, %%ecx;" /* functions may use them as additional */ - "xor %%edx, %%edx;" /* arguments */ + "xor %%edx, %%edx;" /* functions may use them as additional arguments */ "cpuid;" "mov %%ebx, %1;" "pop %%ebx;"

@@ -1893,21 +1891,283 @@ cpuidCall(virCPUx86CPUID *cpuid) } +/* Leaf 0x4

+ * + * Sub leaf n+1 is invalid if eax[4:0] in sub leaf n equals 0. + */ +static int +cpuidSetLeaf4(virCPUx86Data *data, + virCPUx86CPUID *subLeaf0) +{ + virCPUx86CPUID cpuid = *subLeaf0; + + if (virCPUx86DataAddCPUID(data, subLeaf0) < 0) + return -1; + + while (cpuid.eax & 0x1f) { + cpuid.ecx_in++; + cpuidCall(&cpuid); + if (virCPUx86DataAddCPUID(data, &cpuid) < 0) + return -1; + } + return 0; +} + + +/* Leaf 0x7

+ * + * Sub leaf n is invalid if n > eax in sub leaf 0. + */ +static int +cpuidSetLeaf7(virCPUx86Data *data, + virCPUx86CPUID *subLeaf0) +{ + virCPUx86CPUID cpuid = { .eax_in = 0x7 }; + uint32_t sub; + + if (virCPUx86DataAddCPUID(data, subLeaf0) < 0) + return -1; + + for (sub = 1; sub <= subLeaf0->eax; sub++) { + cpuid.ecx_in = sub; + cpuidCall(&cpuid); + if (virCPUx86DataAddCPUID(data, &cpuid) < 0) + return -1; + } + return 0; +} + + +/* Leaf 0xb

+ * + * Sub leaf n is invalid if it returns 0 in ecx[15:8]. + * Sub leaf n+1 is invalid if sub leaf n is invalid. + * Some output values do not depend on ecx, thus sub leaf 0 provides + * meaningful data even if it was (theoretically) considered invalid.

+ */ +static int +cpuidSetLeafB(virCPUx86Data *data, + virCPUx86CPUID *subLeaf0) +{ + virCPUx86CPUID cpuid = *subLeaf0; + + while (cpuid.ecx & 0xff00) { + if (virCPUx86DataAddCPUID(data, &cpuid) < 0) + return -1; + cpuid.ecx_in++; + cpuidCall(&cpuid); + } + return 0; +} + + +/* Leaf 0xd

+ * + * Sub leaves 0 and 1 are valid. + * Sub leaf n (2 <= n < 32) is invalid if eax[n] from sub leaf 0 is not set + * and ecx[n] from sub leaf 1 is not set. + * Sub leaf n (32 <= n < 64) is invalid if edx[n-32] from sub leaf 0 is not set + * and edx[n-32] from sub leaf 1 is not set. + */ +static int +cpuidSetLeafD(virCPUx86Data *data, + virCPUx86CPUID *subLeaf0) +{ + virCPUx86CPUID cpuid = { .eax_in = 0xd }; + virCPUx86CPUID sub0; + virCPUx86CPUID sub1; + uint32_t sub; + + if (virCPUx86DataAddCPUID(data, subLeaf0) < 0) + return -1; + + cpuid.ecx_in = 1; + cpuidCall(&cpuid); + if (virCPUx86DataAddCPUID(data, &cpuid) < 0) + return -1; + + sub0 = *subLeaf0; + sub1 = cpuid; + for (sub = 2; sub < 64; sub++) { + if (sub < 32 && + !(sub0.eax & (1 << sub)) && + !(sub1.ecx & (1 << sub))) + continue; + if (sub >= 32 && + !(sub0.edx & (1 << (sub - 32))) && + !(sub1.edx & (1 << (sub - 32)))) + continue; + + cpuid.ecx_in = sub; + cpuidCall(&cpuid); + if (virCPUx86DataAddCPUID(data, &cpuid) < 0) + return -1; + } + return 0; +} + + +/* Leaf 0xf, 0x10

+ * + * res reports valid resource identification (ResID) starting at bit 1. + * Values associated with each valid ResID are reported by ResID sub leaf. + * + * 0xf: Sub leaf n is valid if edx[n] (= res[ResID]) from sub leaf 0 is set. + * 0x10: Sub leaf n is valid if ebx[n] (= res[ResID]) from sub leaf 0 is set. + */ +static int +cpuidSetLeafResID(virCPUx86Data *data, + virCPUx86CPUID *subLeaf0, + uint32_t res) +{ + virCPUx86CPUID cpuid = { .eax_in = subLeaf0->eax_in }; + uint32_t sub; + + if (virCPUx86DataAddCPUID(data, subLeaf0) < 0) + return -1; + + for (sub = 1; sub < 32; sub++) { + if (!(res & (1 << sub))) + continue; + cpuid.ecx_in = sub; + cpuidCall(&cpuid); + if (virCPUx86DataAddCPUID(data, &cpuid) < 0) + return -1; + } + return 0; +} + + +/* Leaf 0x12

+ * + * Sub leaves 0 and 1 is supported if ebx[2] from leaf 0x7 (SGX) is set. + * Sub leaves n >= 2 are valid as long as eax[3:0] != 0. + */ +static int +cpuidSetLeaf12(virCPUx86Data *data, + virCPUx86CPUID *subLeaf0) +{ + virCPUx86CPUID cpuid = { .eax_in = 0x7 }; + virCPUx86CPUID *cpuid7; + + if (!(cpuid7 = x86DataCpuid(data, &cpuid)) || + !(cpuid7->ebx & (1 << 2))) + return 0; + + if (virCPUx86DataAddCPUID(data, subLeaf0) < 0) + return -1; + + cpuid.eax_in = 0x12; + cpuid.ecx_in = 1; + cpuidCall(&cpuid); + if (virCPUx86DataAddCPUID(data, &cpuid) < 0) + return -1; + + cpuid.ecx_in = 2; + cpuidCall(&cpuid); + while (cpuid.eax & 0xf) { + if (virCPUx86DataAddCPUID(data, &cpuid) < 0) + return -1; + cpuid.ecx_in++; + cpuidCall(&cpuid); + } + return 0; +} + + +/* Leaf 0x14

+ * + * Sub leaf 0 reports the maximum supported sub leaf in eax. + */ +static int +cpuidSetLeaf14(virCPUx86Data *data, + virCPUx86CPUID *subLeaf0) +{ + virCPUx86CPUID cpuid = { .eax_in = 0x14 }; + uint32_t sub; + + if (virCPUx86DataAddCPUID(data, subLeaf0) < 0) + return -1; + + for (sub = 1; sub <= subLeaf0->eax; sub++) { + cpuid.ecx_in = sub; + cpuidCall(&cpuid); + if (virCPUx86DataAddCPUID(data, &cpuid) < 0) + return -1; + } + return 0; +} + + +/* Leaf 0x17

+ * + * Sub leaf 0 is valid if eax >= 3. + * Sub leaf 0 reports the maximum supported sub leaf in eax. + */ +static int +cpuidSetLeaf17(virCPUx86Data *data, + virCPUx86CPUID *subLeaf0) +{ + virCPUx86CPUID cpuid = { .eax_in = 0x17 }; + uint32_t sub; + + if (subLeaf0->eax < 3) + return 0; + + if (virCPUx86DataAddCPUID(data, subLeaf0) < 0) + return -1; + + for (sub = 1; sub <= subLeaf0->eax; sub++) { + cpuid.ecx_in = sub; + cpuidCall(&cpuid); + if (virCPUx86DataAddCPUID(data, &cpuid) < 0) + return -1; + } + return 0; +}