[PATCH] x86/spec-ctrl: Print all AMD speculative hints/features

Andrew Cooper posted 1 patch 2 weeks, 3 days ago
xen/arch/x86/spec_ctrl.c | 13 ++++++++++---
1 file changed, 10 insertions(+), 3 deletions(-)

[PATCH] x86/spec-ctrl: Print all AMD speculative hints/features

Posted by Andrew Cooper 2 weeks, 3 days ago
We already print Intel features that aren't yet implemented/used, so be
consistent on AMD too.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
---
CC: Jan Beulich <JBeulich@suse.com>
CC: Roger Pau Monné <roger.pau@citrix.com>
CC: Wei Liu <wl@xen.org>

For reference, here are the bit layouts on different generations of AMD CPUs.

Fam15, and Zen1:
  (XEN)   Hardware hints:
  (XEN)   Hardware features: IBPB

Zen2:
  (XEN)   Hardware hints: IBRS_FAST IBRS_SAME_MODE
  (XEN)   Hardware features: IBPB IBRS STIBP SSBD

Zen3:
  (XEN)   Hardware hints: STIBP_ALWAYS IBRS_FAST IBRS_SAME_MODE
  (XEN)   Hardware features: IBPB IBRS STIBP SSBD PSFD
---
 xen/arch/x86/spec_ctrl.c | 13 ++++++++++---
 1 file changed, 10 insertions(+), 3 deletions(-)

diff --git a/xen/arch/x86/spec_ctrl.c b/xen/arch/x86/spec_ctrl.c
index f0c67d41b85f..16d2a1d172b5 100644
--- a/xen/arch/x86/spec_ctrl.c
+++ b/xen/arch/x86/spec_ctrl.c
@@ -321,7 +321,7 @@ static void __init print_details(enum ind_thunk thunk, uint64_t caps)
      * 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\n",
+    printk("  Hardware hints:%s%s%s%s%s%s%s%s%s%s%s\n",
            (caps & ARCH_CAPS_RDCL_NO)                        ? " RDCL_NO"        : "",
            (caps & ARCH_CAPS_IBRS_ALL)                       ? " IBRS_ALL"       : "",
            (caps & ARCH_CAPS_RSBA)                           ? " RSBA"           : "",
@@ -329,16 +329,23 @@ static void __init print_details(enum ind_thunk thunk, uint64_t caps)
            (e8b  & cpufeat_mask(X86_FEATURE_SSB_NO)) ||
            (caps & ARCH_CAPS_SSB_NO)                         ? " SSB_NO"         : "",
            (caps & ARCH_CAPS_MDS_NO)                         ? " MDS_NO"         : "",
-           (caps & ARCH_CAPS_TAA_NO)                         ? " TAA_NO"         : "");
+           (caps & ARCH_CAPS_TAA_NO)                         ? " TAA_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"      : "",
+           (e8b  & cpufeat_mask(X86_FEATURE_IBRS_SAME_MODE)) ? " IBRS_SAME_MODE" : "");
 
     /* Hardware features which need driving to mitigate issues. */
-    printk("  Hardware features:%s%s%s%s%s%s%s%s%s\n",
+    printk("  Hardware features:%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)) ||
            (_7d0 & cpufeat_mask(X86_FEATURE_IBRSB))          ? " IBRS"           : "",
+           (e8b  & cpufeat_mask(X86_FEATURE_AMD_STIBP)) ||
            (_7d0 & cpufeat_mask(X86_FEATURE_STIBP))          ? " STIBP"          : "",
            (e8b  & cpufeat_mask(X86_FEATURE_AMD_SSBD)) ||
            (_7d0 & cpufeat_mask(X86_FEATURE_SSBD))           ? " SSBD"           : "",
+           (e8b  & cpufeat_mask(X86_FEATURE_PSFD))           ? " PSFD"           : "",
            (_7d0 & cpufeat_mask(X86_FEATURE_L1D_FLUSH))      ? " L1D_FLUSH"      : "",
            (_7d0 & cpufeat_mask(X86_FEATURE_MD_CLEAR))       ? " MD_CLEAR"       : "",
            (_7d0 & cpufeat_mask(X86_FEATURE_SRBDS_CTRL))     ? " SRBDS_CTRL"     : "",
-- 
2.11.0


Re: [PATCH] x86/spec-ctrl: Print all AMD speculative hints/features

Posted by Jan Beulich 2 weeks, 2 days ago
On 08.09.2021 19:33, Andrew Cooper wrote:
> We already print Intel features that aren't yet implemented/used, so be
> consistent on AMD too.
> 
> Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>

Reviewed-by: Jan Beulich <jbeulich@suse.com>