[Qemu-devel] [PULL 00/12] x86 queue, 2018-06-25

[Qemu-devel] [PULL 00/12] x86 queue, 2018-06-25

[Eduardo Habkost]

The following changes since commit 35e238c9330669882487f9929e0aa97900431853:

  Merge remote-tracking branch 'remotes/kraxel/tags/audio-20180625-pull-request' into staging (2018-06-25 15:25:26 +0100)

are available in the Git repository at:

  git://github.com/ehabkost/qemu.git tags/x86-next-pull-request

for you to fetch changes up to 0b6e9aa89e02c8b213af019aad816e00ba8243f8:

  Merge branch 'master' of git://git.qemu.org/qemu into x86-next (2018-06-25 14:10:56 -0300)

----------------------------------------------------------------
x86 queue, 2018-06-25

* Add TOPOEXT feature to EPYC CPU model
* AMD's amd-ssbd and amd-no-ssbd CPUID features
* Removed unused CPUID flag names: ospke, osxsave
* Better formatting of '-cpu help'

----------------------------------------------------------------

Babu Moger (5):
  i386: Add support for CPUID_8000_001E for AMD
  i386: Allow TOPOEXT to be enabled on older kernels
  i386: Fix up the Node id for CPUID_8000_001E
  i386: Enable TOPOEXT feature on AMD EPYC CPU
  i386: Remove generic SMT thread check

Daniel P. Berrangé (3):
  i386: improve alignment of CPU model listing
  i386: improve sorting of CPU model names
  i386: display known CPUID features linewrapped, in alphabetical order

Eduardo Habkost (2):
  i386: Remove osxsave CPUID flag name
  i386: Remove ospke CPUID flag name

Konrad Rzeszutek Wilk (2):
  i386: define the AMD 'amd-ssbd' CPUID feature bit
  i386: Define AMD's no SSB mitigation needed.

 include/hw/i386/pc.h |  12 +++
 target/i386/cpu.c    | 203 +++++++++++++++++++++++++++++++++++--------
 target/i386/kvm.c    |   7 ++
 3 files changed, 188 insertions(+), 34 deletions(-)

-- 
2.18.0.rc1.1.g3f1ff2140

[Qemu-devel] [PULL 01/12] i386: Add support for CPUID_8000_001E for AMD

[Eduardo Habkost]

From: Babu Moger <babu.moger@amd.com>

Add support for cpuid leaf CPUID_8000_001E. Build the config that closely
match the underlying hardware. Please refer to the Processor Programming
Reference (PPR) for AMD Family 17h Model for more details.

Signed-off-by: Babu Moger <babu.moger@amd.com>
Message-Id: <1528498581-131037-2-git-send-email-babu.moger@amd.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
---
 target/i386/cpu.c | 86 +++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 86 insertions(+)

diff --git a/target/i386/cpu.c b/target/i386/cpu.c
index 1e69e68f25..86fb1a4fb8 100644
--- a/target/i386/cpu.c
+++ b/target/i386/cpu.c
@@ -427,6 +427,87 @@ static void encode_cache_cpuid8000001d(CPUCacheInfo *cache, CPUState *cs,
            (cache->complex_indexing ? CACHE_COMPLEX_IDX : 0);
 }
 
+/* Data structure to hold the configuration info for a given core index */
+struct core_topology {
+    /* core complex id of the current core index */
+    int ccx_id;
+    /*
+     * Adjusted core index for this core in the topology
+     * This can be 0,1,2,3 with max 4 cores in a core complex
+     */
+    int core_id;
+    /* Node id for this core index */
+    int node_id;
+    /* Number of nodes in this config */
+    int num_nodes;
+};
+
+/*
+ * Build the configuration closely match the EPYC hardware. Using the EPYC
+ * hardware configuration values (MAX_CCX, MAX_CORES_IN_CCX, MAX_CORES_IN_NODE)
+ * right now. This could change in future.
+ * nr_cores : Total number of cores in the config
+ * core_id  : Core index of the current CPU
+ * topo     : Data structure to hold all the config info for this core index
+ */
+static void build_core_topology(int nr_cores, int core_id,
+                                struct core_topology *topo)
+{
+    int nodes, cores_in_ccx;
+
+    /* First get the number of nodes required */
+    nodes = nodes_in_socket(nr_cores);
+
+    cores_in_ccx = cores_in_core_complex(nr_cores);
+
+    topo->node_id = core_id / (cores_in_ccx * MAX_CCX);
+    topo->ccx_id = (core_id % (cores_in_ccx * MAX_CCX)) / cores_in_ccx;
+    topo->core_id = core_id % cores_in_ccx;
+    topo->num_nodes = nodes;
+}
+
+/* Encode cache info for CPUID[8000001E] */
+static void encode_topo_cpuid8000001e(CPUState *cs, X86CPU *cpu,
+                                       uint32_t *eax, uint32_t *ebx,
+                                       uint32_t *ecx, uint32_t *edx)
+{
+    struct core_topology topo = {0};
+
+    build_core_topology(cs->nr_cores, cpu->core_id, &topo);
+    *eax = cpu->apic_id;
+    /*
+     * CPUID_Fn8000001E_EBX
+     * 31:16 Reserved
+     * 15:8  Threads per core (The number of threads per core is
+     *       Threads per core + 1)
+     *  7:0  Core id (see bit decoding below)
+     *       SMT:
+     *           4:3 node id
+     *             2 Core complex id
+     *           1:0 Core id
+     *       Non SMT:
+     *           5:4 node id
+     *             3 Core complex id
+     *           1:0 Core id
+     */
+    if (cs->nr_threads - 1) {
+        *ebx = ((cs->nr_threads - 1) << 8) | (topo.node_id << 3) |
+                (topo.ccx_id << 2) | topo.core_id;
+    } else {
+        *ebx = (topo.node_id << 4) | (topo.ccx_id << 3) | topo.core_id;
+    }
+    /*
+     * CPUID_Fn8000001E_ECX
+     * 31:11 Reserved
+     * 10:8  Nodes per processor (Nodes per processor is number of nodes + 1)
+     *  7:0  Node id (see bit decoding below)
+     *         2  Socket id
+     *       1:0  Node id
+     */
+    *ecx = ((topo.num_nodes - 1) << 8) | (cpu->socket_id << 2) | topo.node_id;
+    *edx = 0;
+}
+
 /*
  * Definitions of the hardcoded cache entries we expose:
  * These are legacy cache values. If there is a need to change any
@@ -4120,6 +4201,11 @@ void cpu_x86_cpuid(CPUX86State *env, uint32_t index, uint32_t count,
             break;
         }
         break;
+    case 0x8000001E:
+        assert(cpu->core_id <= 255);
+        encode_topo_cpuid8000001e(cs, cpu,
+                                  eax, ebx, ecx, edx);
+        break;
     case 0xC0000000:
         *eax = env->cpuid_xlevel2;
         *ebx = 0;
-- 
2.18.0.rc1.1.g3f1ff2140

[Qemu-devel] [PULL 02/12] i386: improve alignment of CPU model listing

[Eduardo Habkost]

From: Daniel P. Berrangé <berrange@redhat.com>

Since the addition of the -IBRS CPU model variants, the descriptions
shown by '-cpu help' are not well aligned, as several model names
overflow the space allowed. Right aligning the CPU model names is also
not attractive, because it obscures the common name prefixes of many
models. The CPU model name field needs to be 4 characters larger, and
be left aligned instead.

Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20180606165527.17365-2-berrange@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
---
 target/i386/cpu.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/target/i386/cpu.c b/target/i386/cpu.c
index 86fb1a4fb8..e1d7157d8c 100644
--- a/target/i386/cpu.c
+++ b/target/i386/cpu.c
@@ -3380,7 +3380,7 @@ static void x86_cpu_list_entry(gpointer data, gpointer user_data)
         desc = cc->cpu_def->model_id;
     }
 
-    (*s->cpu_fprintf)(s->file, "x86 %16s  %-48s\n",
+    (*s->cpu_fprintf)(s->file, "x86 %-20s  %-48s\n",
                       name, desc);
     g_free(name);
 }
-- 
2.18.0.rc1.1.g3f1ff2140

[Qemu-devel] [PULL 03/12] i386: improve sorting of CPU model names

[Eduardo Habkost]

From: Daniel P. Berrangé <berrange@redhat.com>

The current list of CPU model names output by "-cpu help" is sorted
alphabetically based on the internal QOM class name. The text that is
displayed, however, uses the CPU model name, which is equivalent to the
QOM class name, minus a suffix. Unfortunately that suffix has an effect
on the sort ordering, for example, causing the various Broadwell
variants to appear reversed:

  x86 486
  x86 Broadwell-IBRS        Intel Core Processor (Broadwell, IBRS)
  x86 Broadwell-noTSX-IBRS  Intel Core Processor (Broadwell, no TSX, IBRS
  x86 Broadwell-noTSX       Intel Core Processor (Broadwell, no TSX)
  x86 Broadwell             Intel Core Processor (Broadwell)
  x86 Conroe                Intel Celeron_4x0 (Conroe/Merom Class Core 2)

By sorting on the actual CPU model name text that is displayed, the
result is

  x86 486
  x86 Broadwell             Intel Core Processor (Broadwell)
  x86 Broadwell-IBRS        Intel Core Processor (Broadwell, IBRS)
  x86 Broadwell-noTSX       Intel Core Processor (Broadwell, no TSX)
  x86 Broadwell-noTSX-IBRS  Intel Core Processor (Broadwell, no TSX, IBRS)
  x86 Conroe                Intel Celeron_4x0 (Conroe/Merom Class Core 2)

This requires extra string allocations during sorting, but this is not a
concern given the usage scenario and the number of CPU models that exist.

Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20180606165527.17365-3-berrange@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
---
 target/i386/cpu.c | 14 +++++++++-----
 1 file changed, 9 insertions(+), 5 deletions(-)

diff --git a/target/i386/cpu.c b/target/i386/cpu.c
index e1d7157d8c..19ac1e6569 100644
--- a/target/i386/cpu.c
+++ b/target/i386/cpu.c
@@ -3351,15 +3351,19 @@ static gint x86_cpu_list_compare(gconstpointer a, gconstpointer b)
     ObjectClass *class_b = (ObjectClass *)b;
     X86CPUClass *cc_a = X86_CPU_CLASS(class_a);
     X86CPUClass *cc_b = X86_CPU_CLASS(class_b);
-    const char *name_a, *name_b;
+    char *name_a, *name_b;
+    int ret;
 
     if (cc_a->ordering != cc_b->ordering) {
-        return cc_a->ordering - cc_b->ordering;
+        ret = cc_a->ordering - cc_b->ordering;
     } else {
-        name_a = object_class_get_name(class_a);
-        name_b = object_class_get_name(class_b);
-        return strcmp(name_a, name_b);
+        name_a = x86_cpu_class_get_model_name(cc_a);
+        name_b = x86_cpu_class_get_model_name(cc_b);
+        ret = strcmp(name_a, name_b);
+        g_free(name_a);
+        g_free(name_b);
     }
+    return ret;
 }
 
 static GSList *get_sorted_cpu_model_list(void)
-- 
2.18.0.rc1.1.g3f1ff2140

[Qemu-devel] [PULL 04/12] i386: display known CPUID features linewrapped, in alphabetical order

[Eduardo Habkost]

From: Daniel P. Berrangé <berrange@redhat.com>

When using '-cpu help' the list of CPUID features is grouped according
to the internal low level CPUID grouping. The data printed results in
very long lines too.

This combines to make it hard for users to read the output and identify
if QEMU knows about the feature they wish to use.

This change gets rid of the grouping of features and treats all flags as
single list. The list is sorted into alphabetical order and the printing
with line wrapping at the 77th column.

Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20180606165527.17365-4-berrange@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
---
 target/i386/cpu.c | 41 +++++++++++++++++++++++++++--------------
 1 file changed, 27 insertions(+), 14 deletions(-)

diff --git a/target/i386/cpu.c b/target/i386/cpu.c
index 19ac1e6569..9da4920421 100644
--- a/target/i386/cpu.c
+++ b/target/i386/cpu.c
@@ -3331,17 +3331,21 @@ static void x86_cpu_class_check_missing_features(X86CPUClass *xcc,
 
 /* Print all cpuid feature names in featureset
  */
-static void listflags(FILE *f, fprintf_function print, const char **featureset)
+static void listflags(FILE *f, fprintf_function print, GList *features)
 {
-    int bit;
-    bool first = true;
-
-    for (bit = 0; bit < 32; bit++) {
-        if (featureset[bit]) {
-            print(f, "%s%s", first ? "" : " ", featureset[bit]);
-            first = false;
+    size_t len = 0;
+    GList *tmp;
+
+    for (tmp = features; tmp; tmp = tmp->next) {
+        const char *name = tmp->data;
+        if ((len + strlen(name) + 1) >= 75) {
+            print(f, "\n");
+            len = 0;
         }
+        print(f, "%s%s", len == 0 ? "  " : " ", name);
+        len += strlen(name) + 1;
     }
+    print(f, "\n");
 }
 
 /* Sort alphabetically by type name, respecting X86CPUClass::ordering. */
@@ -3392,26 +3396,35 @@ static void x86_cpu_list_entry(gpointer data, gpointer user_data)
 /* list available CPU models and flags */
 void x86_cpu_list(FILE *f, fprintf_function cpu_fprintf)
 {
-    int i;
+    int i, j;
     CPUListState s = {
         .file = f,
         .cpu_fprintf = cpu_fprintf,
     };
     GSList *list;
+    GList *names = NULL;
 
     (*cpu_fprintf)(f, "Available CPUs:\n");
     list = get_sorted_cpu_model_list();
     g_slist_foreach(list, x86_cpu_list_entry, &s);
     g_slist_free(list);
 
-    (*cpu_fprintf)(f, "\nRecognized CPUID flags:\n");
+    names = NULL;
     for (i = 0; i < ARRAY_SIZE(feature_word_info); i++) {
         FeatureWordInfo *fw = &feature_word_info[i];
-
-        (*cpu_fprintf)(f, "  ");
-        listflags(f, cpu_fprintf, fw->feat_names);
-        (*cpu_fprintf)(f, "\n");
+        for (j = 0; j < 32; j++) {
+            if (fw->feat_names[j]) {
+                names = g_list_append(names, (gpointer)fw->feat_names[j]);
+            }
+        }
     }
+
+    names = g_list_sort(names, (GCompareFunc)strcmp);
+
+    (*cpu_fprintf)(f, "\nRecognized CPUID flags:\n");
+    listflags(f, cpu_fprintf, names);
+    (*cpu_fprintf)(f, "\n");
+    g_list_free(names);
 }
 
 static void x86_cpu_definition_entry(gpointer data, gpointer user_data)
-- 
2.18.0.rc1.1.g3f1ff2140

[Qemu-devel] [PULL 05/12] i386: Remove osxsave CPUID flag name

[Eduardo Habkost]

OSXAVE is not a static feature flag: it changes dynamically at
runtime depending on CR4, and it was never configurable: KVM
never returned OSXSAVE on GET_SUPPORTED_CPUID, and it is not
included in TCG_EXT_FEATURES.

Remove OSXSAVE from the feature name array so users don't try to
configure it manually.

Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Message-Id: <20180611203855.13269-1-ehabkost@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
---
 target/i386/cpu.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/target/i386/cpu.c b/target/i386/cpu.c
index 9da4920421..60deae3100 100644
--- a/target/i386/cpu.c
+++ b/target/i386/cpu.c
@@ -788,7 +788,7 @@ static FeatureWordInfo feature_word_info[FEATURE_WORDS] = {
             "fma", "cx16", "xtpr", "pdcm",
             NULL, "pcid", "dca", "sse4.1",
             "sse4.2", "x2apic", "movbe", "popcnt",
-            "tsc-deadline", "aes", "xsave", "osxsave",
+            "tsc-deadline", "aes", "xsave", NULL /* osxsave */,
             "avx", "f16c", "rdrand", "hypervisor",
         },
         .cpuid_eax = 1, .cpuid_reg = R_ECX,
-- 
2.18.0.rc1.1.g3f1ff2140

[Qemu-devel] [PULL 06/12] i386: Remove ospke CPUID flag name

[Eduardo Habkost]

OSPKE is not a static feature flag: it changes dynamically at
runtime depending on CR4, and it was never configurable: KVM
never returned OSPKE on GET_SUPPORTED_CPUID, and on TCG enables
it automatically if CR4_PKE_MASK is set.

Remove OSPKE from the feature name array so users don't try to
configure it manually.

Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Message-Id: <20180611203712.12086-1-ehabkost@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
---
 target/i386/cpu.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/target/i386/cpu.c b/target/i386/cpu.c
index 60deae3100..d7dfefcde0 100644
--- a/target/i386/cpu.c
+++ b/target/i386/cpu.c
@@ -738,7 +738,8 @@ static void x86_cpu_vendor_words2str(char *dst, uint32_t vendor1,
           CPUID_7_0_EBX_HLE, CPUID_7_0_EBX_AVX2,
           CPUID_7_0_EBX_INVPCID, CPUID_7_0_EBX_RTM,
           CPUID_7_0_EBX_RDSEED */
-#define TCG_7_0_ECX_FEATURES (CPUID_7_0_ECX_PKU | CPUID_7_0_ECX_OSPKE | \
+#define TCG_7_0_ECX_FEATURES (CPUID_7_0_ECX_PKU | \
+          /* CPUID_7_0_ECX_OSPKE is dynamic */ \
           CPUID_7_0_ECX_LA57)
 #define TCG_7_0_EDX_FEATURES 0
 #define TCG_APM_FEATURES 0
@@ -955,7 +956,7 @@ static FeatureWordInfo feature_word_info[FEATURE_WORDS] = {
     [FEAT_7_0_ECX] = {
         .feat_names = {
             NULL, "avx512vbmi", "umip", "pku",
-            "ospke", NULL, "avx512vbmi2", NULL,
+            NULL /* ospke */, NULL, "avx512vbmi2", NULL,
             "gfni", "vaes", "vpclmulqdq", "avx512vnni",
             "avx512bitalg", NULL, "avx512-vpopcntdq", NULL,
             "la57", NULL, NULL, NULL,
-- 
2.18.0.rc1.1.g3f1ff2140

[Qemu-devel] [PULL 07/12] i386: define the AMD 'amd-ssbd' CPUID feature bit

[Eduardo Habkost]

From: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>

AMD future CPUs expose _two_ ways to utilize the Intel equivalant
of the Speculative Store Bypass Disable. The first is via
the virtualized VIRT_SPEC CTRL MSR (0xC001_011f) and the second
is via the SPEC_CTRL MSR (0x48). The document titled:
124441_AMD64_SpeculativeStoreBypassDisable_Whitepaper_final.pdf

gives priority of SPEC CTRL MSR over the VIRT SPEC CTRL MSR.

A copy of this document is available at
      https://bugzilla.kernel.org/show_bug.cgi?id=199889

Anyhow, this means that on future AMD CPUs there will be  _two_ ways to
deal with SSBD.

Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Message-Id: <20180601153809.15259-2-konrad.wilk@oracle.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
---
 target/i386/cpu.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/target/i386/cpu.c b/target/i386/cpu.c
index d7dfefcde0..7234bebfcb 100644
--- a/target/i386/cpu.c
+++ b/target/i386/cpu.c
@@ -1009,7 +1009,7 @@ static FeatureWordInfo feature_word_info[FEATURE_WORDS] = {
             "ibpb", NULL, NULL, NULL,
             NULL, NULL, NULL, NULL,
             NULL, NULL, NULL, NULL,
-            NULL, "virt-ssbd", NULL, NULL,
+            "amd-ssbd", "virt-ssbd", NULL, NULL,
             NULL, NULL, NULL, NULL,
         },
         .cpuid_eax = 0x80000008,
-- 
2.18.0.rc1.1.g3f1ff2140

[Qemu-devel] [PULL 08/12] i386: Define AMD's no SSB mitigation needed.

[Eduardo Habkost]

From: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>

AMD future CPUs expose a mechanism to tell the guest that the
Speculative Store Bypass Disable is not needed and that the
CPU is all good.

This is exposed via the CPUID 8000_0008.EBX[26] bit.

See 124441_AMD64_SpeculativeStoreBypassDisable_Whitepaper_final.pdf

A copy of this document is available at
        https://bugzilla.kernel.org/show_bug.cgi?id=199889

Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Message-Id: <20180601153809.15259-3-konrad.wilk@oracle.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
---
 target/i386/cpu.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/target/i386/cpu.c b/target/i386/cpu.c
index 7234bebfcb..7a4484bb06 100644
--- a/target/i386/cpu.c
+++ b/target/i386/cpu.c
@@ -1009,7 +1009,7 @@ static FeatureWordInfo feature_word_info[FEATURE_WORDS] = {
             "ibpb", NULL, NULL, NULL,
             NULL, NULL, NULL, NULL,
             NULL, NULL, NULL, NULL,
-            "amd-ssbd", "virt-ssbd", NULL, NULL,
+            "amd-ssbd", "virt-ssbd", "amd-no-ssb", NULL,
             NULL, NULL, NULL, NULL,
         },
         .cpuid_eax = 0x80000008,
-- 
2.18.0.rc1.1.g3f1ff2140

[Qemu-devel] [PULL 09/12] i386: Allow TOPOEXT to be enabled on older kernels

[Eduardo Habkost]

From: Babu Moger <babu.moger@amd.com>

Enabling TOPOEXT feature might cause compatibility issues if
older kernels does not set this feature. Lets set this feature
unconditionally.

Signed-off-by: Babu Moger <babu.moger@amd.com>
Message-Id: <1528939107-17193-2-git-send-email-babu.moger@amd.com>
[ehabkost: rewrite comment and commit message]
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
---
 target/i386/kvm.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/target/i386/kvm.c b/target/i386/kvm.c
index 445e0e0b11..2d174f3a91 100644
--- a/target/i386/kvm.c
+++ b/target/i386/kvm.c
@@ -372,6 +372,13 @@ uint32_t kvm_arch_get_supported_cpuid(KVMState *s, uint32_t function,
         if (host_tsx_blacklisted()) {
             ret &= ~(CPUID_7_0_EBX_RTM | CPUID_7_0_EBX_HLE);
         }
+    } else if (function == 0x80000001 && reg == R_ECX) {
+        /*
+         * It's safe to enable TOPOEXT even if it's not returned by
+         * GET_SUPPORTED_CPUID.  Unconditionally enabling TOPOEXT here allows
+         * us to keep CPU models including TOPOEXT runnable on older kernels.
+         */
+        ret |= CPUID_EXT3_TOPOEXT;
     } else if (function == 0x80000001 && reg == R_EDX) {
         /* On Intel, kvm returns cpuid according to the Intel spec,
          * so add missing bits according to the AMD spec:
-- 
2.18.0.rc1.1.g3f1ff2140

[Qemu-devel] [PULL 10/12] i386: Fix up the Node id for CPUID_8000_001E

[Eduardo Habkost]

From: Babu Moger <babu.moger@amd.com>

This is part of topoext support. To keep the compatibility, it is better
we support all the combination of nr_cores and nr_threads currently
supported. By allowing more nr_cores and nr_threads, we might end up with
more nodes than we can actually support with the real hardware. We need to
fix up the node id to make this work. We can achieve this by shifting the
socket_id bits left to address more nodes.

Signed-off-by: Babu Moger <babu.moger@amd.com>
Message-Id: <1529443919-67509-2-git-send-email-babu.moger@amd.com>
Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
---
 target/i386/cpu.c | 26 +++++++++++++++++++++++++-
 1 file changed, 25 insertions(+), 1 deletion(-)

diff --git a/target/i386/cpu.c b/target/i386/cpu.c
index 7a4484bb06..130391c840 100644
--- a/target/i386/cpu.c
+++ b/target/i386/cpu.c
@@ -19,6 +19,7 @@
 
 #include "qemu/osdep.h"
 #include "qemu/cutils.h"
+#include "qemu/bitops.h"
 
 #include "cpu.h"
 #include "exec/exec-all.h"
@@ -472,6 +473,8 @@ static void encode_topo_cpuid8000001e(CPUState *cs, X86CPU *cpu,
                                        uint32_t *ecx, uint32_t *edx)
 {
     struct core_topology topo = {0};
+    unsigned long nodes;
+    int shift;
 
     build_core_topology(cs->nr_cores, cpu->core_id, &topo);
     *eax = cpu->apic_id;
@@ -504,7 +507,28 @@ static void encode_topo_cpuid8000001e(CPUState *cs, X86CPU *cpu,
      *         2  Socket id
      *       1:0  Node id
      */
-    *ecx = ((topo.num_nodes - 1) << 8) | (cpu->socket_id << 2) | topo.node_id;
+    if (topo.num_nodes <= 4) {
+        *ecx = ((topo.num_nodes - 1) << 8) | (cpu->socket_id << 2) |
+                topo.node_id;
+    } else {
+        /*
+         * Node id fix up. Actual hardware supports up to 4 nodes. But with
+         * more than 32 cores, we may end up with more than 4 nodes.
+         * Node id is a combination of socket id and node id. Only requirement
+         * here is that this number should be unique accross the system.
+         * Shift the socket id to accommodate more nodes. We dont expect both
+         * socket id and node id to be big number at the same time. This is not
+         * an ideal config but we need to to support it. Max nodes we can have
+         * is 32 (255/8) with 8 cores per node and 255 max cores. We only need
+         * 5 bits for nodes. Find the left most set bit to represent the total
+         * number of nodes. find_last_bit returns last set bit(0 based). Left
+         * shift(+1) the socket id to represent all the nodes.
+         */
+        nodes = topo.num_nodes - 1;
+        shift = find_last_bit(&nodes, 8);
+        *ecx = ((topo.num_nodes - 1) << 8) | (cpu->socket_id << (shift + 1)) |
+                topo.node_id;
+    }
     *edx = 0;
 }
 
-- 
2.18.0.rc1.1.g3f1ff2140

[Qemu-devel] [PULL 11/12] i386: Enable TOPOEXT feature on AMD EPYC CPU

[Eduardo Habkost]

From: Babu Moger <babu.moger@amd.com>

Enable TOPOEXT feature on EPYC CPU. This is required to support
hyperthreading on VM guests. Also extend xlevel to 0x8000001E.

Disable topoext on PC_COMPAT_2_12 and keep xlevel 0x8000000a.

Signed-off-by: Babu Moger <babu.moger@amd.com>
Message-Id: <1529443919-67509-3-git-send-email-babu.moger@amd.com>
[ehabkost: Added EPYC-IBPB.xlevel to PC_COMPAT_2_12]
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
---
 include/hw/i386/pc.h | 12 ++++++++++++
 target/i386/cpu.c    | 10 ++++++----
 2 files changed, 18 insertions(+), 4 deletions(-)

diff --git a/include/hw/i386/pc.h b/include/hw/i386/pc.h
index fc8dedca12..316230e570 100644
--- a/include/hw/i386/pc.h
+++ b/include/hw/i386/pc.h
@@ -303,6 +303,18 @@ bool e820_get_entry(int, uint32_t, uint64_t *, uint64_t *);
         .driver   = TYPE_X86_CPU,\
         .property = "legacy-cache",\
         .value    = "on",\
+    },{\
+        .driver   = TYPE_X86_CPU,\
+        .property = "topoext",\
+        .value    = "off",\
+    },{\
+        .driver   = "EPYC-" TYPE_X86_CPU,\
+        .property = "xlevel",\
+        .value    = stringify(0x8000000a),\
+    },{\
+        .driver   = "EPYC-IBPB" TYPE_X86_CPU,\
+        .property = "xlevel",\
+        .value    = stringify(0x8000000a),\
     },
 
 #define PC_COMPAT_2_11 \
diff --git a/target/i386/cpu.c b/target/i386/cpu.c
index 130391c840..d6ed29b484 100644
--- a/target/i386/cpu.c
+++ b/target/i386/cpu.c
@@ -2579,7 +2579,8 @@ static X86CPUDefinition builtin_x86_defs[] = {
         .features[FEAT_8000_0001_ECX] =
             CPUID_EXT3_OSVW | CPUID_EXT3_3DNOWPREFETCH |
             CPUID_EXT3_MISALIGNSSE | CPUID_EXT3_SSE4A | CPUID_EXT3_ABM |
-            CPUID_EXT3_CR8LEG | CPUID_EXT3_SVM | CPUID_EXT3_LAHF_LM,
+            CPUID_EXT3_CR8LEG | CPUID_EXT3_SVM | CPUID_EXT3_LAHF_LM |
+            CPUID_EXT3_TOPOEXT,
         .features[FEAT_7_0_EBX] =
             CPUID_7_0_EBX_FSGSBASE | CPUID_7_0_EBX_BMI1 | CPUID_7_0_EBX_AVX2 |
             CPUID_7_0_EBX_SMEP | CPUID_7_0_EBX_BMI2 | CPUID_7_0_EBX_RDSEED |
@@ -2594,7 +2595,7 @@ static X86CPUDefinition builtin_x86_defs[] = {
             CPUID_XSAVE_XGETBV1,
         .features[FEAT_6_EAX] =
             CPUID_6_EAX_ARAT,
-        .xlevel = 0x8000000A,
+        .xlevel = 0x8000001E,
         .model_id = "AMD EPYC Processor",
         .cache_info = &epyc_cache_info,
     },
@@ -2624,7 +2625,8 @@ static X86CPUDefinition builtin_x86_defs[] = {
         .features[FEAT_8000_0001_ECX] =
             CPUID_EXT3_OSVW | CPUID_EXT3_3DNOWPREFETCH |
             CPUID_EXT3_MISALIGNSSE | CPUID_EXT3_SSE4A | CPUID_EXT3_ABM |
-            CPUID_EXT3_CR8LEG | CPUID_EXT3_SVM | CPUID_EXT3_LAHF_LM,
+            CPUID_EXT3_CR8LEG | CPUID_EXT3_SVM | CPUID_EXT3_LAHF_LM |
+            CPUID_EXT3_TOPOEXT,
         .features[FEAT_8000_0008_EBX] =
             CPUID_8000_0008_EBX_IBPB,
         .features[FEAT_7_0_EBX] =
@@ -2641,7 +2643,7 @@ static X86CPUDefinition builtin_x86_defs[] = {
             CPUID_XSAVE_XGETBV1,
         .features[FEAT_6_EAX] =
             CPUID_6_EAX_ARAT,
-        .xlevel = 0x8000000A,
+        .xlevel = 0x8000001E,
         .model_id = "AMD EPYC Processor (with IBPB)",
         .cache_info = &epyc_cache_info,
     },
-- 
2.18.0.rc1.1.g3f1ff2140

[Qemu-devel] [PULL 12/12] i386: Remove generic SMT thread check

[Eduardo Habkost]

From: Babu Moger <babu.moger@amd.com>

Remove generic non-intel check while validating hyperthreading support.
Certain AMD CPUs can support hyperthreading now.

CPU family with TOPOEXT feature can support hyperthreading now.

Signed-off-by: Babu Moger <babu.moger@amd.com>
Tested-by: Geoffrey McRae <geoff@hostfission.com>
Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
Message-Id: <1529443919-67509-4-git-send-email-babu.moger@amd.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
---
 target/i386/cpu.c | 17 +++++++++++------
 1 file changed, 11 insertions(+), 6 deletions(-)

diff --git a/target/i386/cpu.c b/target/i386/cpu.c
index d6ed29b484..e6c2f8a22a 100644
--- a/target/i386/cpu.c
+++ b/target/i386/cpu.c
@@ -4985,17 +4985,22 @@ static void x86_cpu_realizefn(DeviceState *dev, Error **errp)
 
     qemu_init_vcpu(cs);
 
-    /* Only Intel CPUs support hyperthreading. Even though QEMU fixes this
-     * issue by adjusting CPUID_0000_0001_EBX and CPUID_8000_0008_ECX
-     * based on inputs (sockets,cores,threads), it is still better to gives
+    /*
+     * Most Intel and certain AMD CPUs support hyperthreading. Even though QEMU
+     * fixes this issue by adjusting CPUID_0000_0001_EBX and CPUID_8000_0008_ECX
+     * based on inputs (sockets,cores,threads), it is still better to give
      * users a warning.
      *
      * NOTE: the following code has to follow qemu_init_vcpu(). Otherwise
      * cs->nr_threads hasn't be populated yet and the checking is incorrect.
      */
-    if (!IS_INTEL_CPU(env) && cs->nr_threads > 1 && !ht_warned) {
-        error_report("AMD CPU doesn't support hyperthreading. Please configure"
-                     " -smp options properly.");
+     if (IS_AMD_CPU(env) &&
+         !(env->features[FEAT_8000_0001_ECX] & CPUID_EXT3_TOPOEXT) &&
+         cs->nr_threads > 1 && !ht_warned) {
+            error_report("This family of AMD CPU doesn't support "
+                         "hyperthreading(%d). Please configure -smp "
+                         "options properly or try enabling topoext feature.",
+                         cs->nr_threads);
         ht_warned = true;
     }
 
-- 
2.18.0.rc1.1.g3f1ff2140

Re: [Qemu-devel] [PULL 00/12] x86 queue, 2018-06-25

[Peter Maydell]

On 25 June 2018 at 23:25, Eduardo Habkost <ehabkost@redhat.com> wrote:
> The following changes since commit 35e238c9330669882487f9929e0aa97900431853:
>
>   Merge remote-tracking branch 'remotes/kraxel/tags/audio-20180625-pull-request' into staging (2018-06-25 15:25:26 +0100)
>
> are available in the Git repository at:
>
>   git://github.com/ehabkost/qemu.git tags/x86-next-pull-request
>
> for you to fetch changes up to 0b6e9aa89e02c8b213af019aad816e00ba8243f8:
>
>   Merge branch 'master' of git://git.qemu.org/qemu into x86-next (2018-06-25 14:10:56 -0300)
>
> ----------------------------------------------------------------
> x86 queue, 2018-06-25
>
> * Add TOPOEXT feature to EPYC CPU model
> * AMD's amd-ssbd and amd-no-ssbd CPUID features
> * Removed unused CPUID flag names: ospke, osxsave
> * Better formatting of '-cpu help'
>
Applied, thanks.

-- PMM

Re: [Qemu-devel] [PULL 09/12] i386: Allow TOPOEXT to be enabled on older kernels

[Richard W.M. Jones]

On Mon, Jun 25, 2018 at 07:25:21PM -0300, Eduardo Habkost wrote:
> From: Babu Moger <babu.moger@amd.com>
> 
> Enabling TOPOEXT feature might cause compatibility issues if
> older kernels does not set this feature. Lets set this feature
> unconditionally.
> 
> Signed-off-by: Babu Moger <babu.moger@amd.com>
> Message-Id: <1528939107-17193-2-git-send-email-babu.moger@amd.com>
> [ehabkost: rewrite comment and commit message]
> Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
> ---
>  target/i386/kvm.c | 7 +++++++
>  1 file changed, 7 insertions(+)
> 
> diff --git a/target/i386/kvm.c b/target/i386/kvm.c
> index 445e0e0b11..2d174f3a91 100644
> --- a/target/i386/kvm.c
> +++ b/target/i386/kvm.c
> @@ -372,6 +372,13 @@ uint32_t kvm_arch_get_supported_cpuid(KVMState *s, uint32_t function,
>          if (host_tsx_blacklisted()) {
>              ret &= ~(CPUID_7_0_EBX_RTM | CPUID_7_0_EBX_HLE);
>          }
> +    } else if (function == 0x80000001 && reg == R_ECX) {
> +        /*
> +         * It's safe to enable TOPOEXT even if it's not returned by
> +         * GET_SUPPORTED_CPUID.  Unconditionally enabling TOPOEXT here allows
> +         * us to keep CPU models including TOPOEXT runnable on older kernels.
> +         */
> +        ret |= CPUID_EXT3_TOPOEXT;
>      } else if (function == 0x80000001 && reg == R_EDX) {
>          /* On Intel, kvm returns cpuid according to the Intel spec,
>           * so add missing bits according to the AMD spec:

This commit breaks KVM (not TCG) with -cpu host on:

  AMD Phenom(tm) 9600B Quad-Core Processor

More details including full qemu command line etc in this bug:

  https://bugzilla.redhat.com/show_bug.cgi?id=1613277

Rich.

-- 
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