x86/spec-ctrl: Enumerations for Gather Data Sampling

GDS_CTRL is introduced by the August 2023 microcode.  GDS_NO is for current
and future processors not susceptible to GDS.

This is part of XSA-435 / CVE-2022-40982

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
(cherry picked from commit 9f585f59d90c8d3a1b21369a852b7d7eee8a29b9)

diff --git a/tools/misc/xen-cpuid.c b/tools/misc/xen-cpuid.c
index 10421cbdbda6699138d705c269691279d0292a41..d2912c096b313617f4cdc8d039028147c2c229c6 100644 (file)
--- a/tools/misc/xen-cpuid.c
+++ b/tools/misc/xen-cpuid.c
@@ -235,7 +235,8 @@ static const char *const str_m10Al[32] =
     [18] = "fb-clear-ctrl",       [19] = "rrsba",
     [20] = "bhi-no",              [21] = "xapic-status",
     /* 22 */                      [23] = "ovrclk-status",
-    [24] = "pbrsb-no",
+    [24] = "pbrsb-no",            [25] = "gds-ctrl",
+    [26] = "gds-no",
 };
 
 static const char *const str_m10Ah[32] =

diff --git a/xen/arch/x86/include/asm/cpufeature.h b/xen/arch/x86/include/asm/cpufeature.h
index ec9456e1fdc3098eca7cec1a66334b3554c9e9ac..458806cc8cdf1c2f327a2b675ac604fd63428c97 100644 (file)
--- a/xen/arch/x86/include/asm/cpufeature.h
+++ b/xen/arch/x86/include/asm/cpufeature.h
@@ -156,6 +156,8 @@
 #define cpu_has_taa_no          boot_cpu_has(X86_FEATURE_TAA_NO)
 #define cpu_has_fb_clear        boot_cpu_has(X86_FEATURE_FB_CLEAR)
 #define cpu_has_rrsba           boot_cpu_has(X86_FEATURE_RRSBA)
+#define cpu_has_gds_ctrl        boot_cpu_has(X86_FEATURE_GDS_CTRL)
+#define cpu_has_gds_no          boot_cpu_has(X86_FEATURE_GDS_NO)
 
 /* Synthesized. */
 #define cpu_has_arch_perfmon    boot_cpu_has(X86_FEATURE_ARCH_PERFMON)

diff --git a/xen/arch/x86/include/asm/msr-index.h b/xen/arch/x86/include/asm/msr-index.h
index 40450b66ad7517aa6826af873f54764247ac7dfd..2e0f9caee09072555b891d3ee2f736f62974e1ed 100644 (file)
--- a/xen/arch/x86/include/asm/msr-index.h
+++ b/xen/arch/x86/include/asm/msr-index.h
@@ -86,6 +86,8 @@
 #define  ARCH_CAPS_RRSBA                    (_AC(1, ULL) << 19)
 #define  ARCH_CAPS_BHI_NO                   (_AC(1, ULL) << 20)
 #define  ARCH_CAPS_PBRSB_NO                 (_AC(1, ULL) << 24)
+#define  ARCH_CAPS_GDS_CTRL                 (_AC(1, ULL) << 25)
+#define  ARCH_CAPS_GDS_NO                   (_AC(1, ULL) << 26)
 
 #define MSR_FLUSH_CMD                       0x0000010b
 #define  FLUSH_CMD_L1D                      (_AC(1, ULL) <<  0)
@@ -104,6 +106,8 @@
 #define  MCU_OPT_CTRL_RTM_ALLOW             (_AC(1, ULL) <<  1)
 #define  MCU_OPT_CTRL_RTM_LOCKED            (_AC(1, ULL) <<  2)
 #define  MCU_OPT_CTRL_FB_CLEAR_DIS          (_AC(1, ULL) <<  3)
+#define  MCU_OPT_CTRL_GDS_MIT_DIS           (_AC(1, ULL) <<  4)
+#define  MCU_OPT_CTRL_GDS_MIT_LOCK          (_AC(1, ULL) <<  5)
 
 #define MSR_RTIT_OUTPUT_BASE                0x00000560
 #define MSR_RTIT_OUTPUT_MASK                0x00000561

diff --git a/xen/arch/x86/spec_ctrl.c b/xen/arch/x86/spec_ctrl.c
index c42ec3b8f670353b37662f5e5e40edc2491d70a0..d79374d63cfebb52a029f783ab8c07ee98ce8dc4 100644 (file)
--- a/xen/arch/x86/spec_ctrl.c
+++ b/xen/arch/x86/spec_ctrl.c
@@ -423,7 +423,7 @@ static void __init print_details(enum ind_thunk thunk)
      * Hardware read-only information, stating immunity to certain issues, or
      * suggestions of which mitigation to use.
      */
-    printk("  Hardware hints:%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s\n",
+    printk("  Hardware hints:%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s\n",
            (caps & ARCH_CAPS_RDCL_NO)                        ? " RDCL_NO"        : "",
            (caps & ARCH_CAPS_EIBRS)                          ? " EIBRS"          : "",
            (caps & ARCH_CAPS_RSBA)                           ? " RSBA"           : "",
@@ -438,6 +438,7 @@ static void __init print_details(enum ind_thunk thunk)
            (caps & ARCH_CAPS_PSDP_NO)                        ? " PSDP_NO"        : "",
            (caps & ARCH_CAPS_FB_CLEAR)                       ? " FB_CLEAR"       : "",
            (caps & ARCH_CAPS_PBRSB_NO)                       ? " PBRSB_NO"       : "",
+           (caps & ARCH_CAPS_GDS_NO)                         ? " GDS_NO"         : "",
            (e8b  & cpufeat_mask(X86_FEATURE_IBRS_ALWAYS))    ? " IBRS_ALWAYS"    : "",
            (e8b  & cpufeat_mask(X86_FEATURE_STIBP_ALWAYS))   ? " STIBP_ALWAYS"   : "",
            (e8b  & cpufeat_mask(X86_FEATURE_IBRS_FAST))      ? " IBRS_FAST"      : "",
@@ -448,7 +449,7 @@ static void __init print_details(enum ind_thunk thunk)
            (e21a & cpufeat_mask(X86_FEATURE_SRSO_NO))        ? " SRSO_NO"        : "");
 
     /* Hardware features which need driving to mitigate issues. */
-    printk("  Hardware features:%s%s%s%s%s%s%s%s%s%s%s%s\n",
+    printk("  Hardware features:%s%s%s%s%s%s%s%s%s%s%s%s%s\n",
            (e8b  & cpufeat_mask(X86_FEATURE_IBPB)) ||
            (_7d0 & cpufeat_mask(X86_FEATURE_IBRSB))          ? " IBPB"           : "",
            (e8b  & cpufeat_mask(X86_FEATURE_IBRS)) ||
@@ -465,6 +466,7 @@ static void __init print_details(enum ind_thunk thunk)
            (e8b  & cpufeat_mask(X86_FEATURE_VIRT_SSBD))      ? " VIRT_SSBD"      : "",
            (caps & ARCH_CAPS_TSX_CTRL)                       ? " TSX_CTRL"       : "",
            (caps & ARCH_CAPS_FB_CLEAR_CTRL)                  ? " FB_CLEAR_CTRL"  : "",
+           (caps & ARCH_CAPS_GDS_CTRL)                       ? " GDS_CTRL"       : "",
            (e21a & cpufeat_mask(X86_FEATURE_SBPB))           ? " SBPB"           : "");
 
     /* Compiled-in support which pertains to mitigations. */

diff --git a/xen/include/public/arch-x86/cpufeatureset.h b/xen/include/public/arch-x86/cpufeatureset.h
index 2fc8158024558a12d498c01767c345fbfd6540eb..d6ce4af6f58a21478f6191eef52239179c44c8fa 100644 (file)
--- a/xen/include/public/arch-x86/cpufeatureset.h
+++ b/xen/include/public/arch-x86/cpufeatureset.h
@@ -327,6 +327,8 @@ XEN_CPUFEATURE(BHI_NO,             16*32+20) /*A  No Branch History Injection  *
 XEN_CPUFEATURE(XAPIC_STATUS,       16*32+21) /*   MSR_XAPIC_DISABLE_STATUS */
 XEN_CPUFEATURE(OVRCLK_STATUS,      16*32+23) /*   MSR_OVERCLOCKING_STATUS */
 XEN_CPUFEATURE(PBRSB_NO,           16*32+24) /*A  No Post-Barrier RSB predictions */
+XEN_CPUFEATURE(GDS_CTRL,           16*32+25) /*   MCU_OPT_CTRL.GDS_MIT_{DIS,LOCK} */
+XEN_CPUFEATURE(GDS_NO,             16*32+26) /*A  No Gather Data Sampling */
 
 /* Intel-defined CPU features, MSR_ARCH_CAPS 0x10a.edx, word 17 */