x86/sysctl: Retrofit XEN_SYSCTL_cpu_featureset_{pv,hvm}_max

Featuresets are supposed to be disappearing when the CPU policy infrastructure
is complete, but that has taken longer than expected, and isn't going to be
complete imminently either.

In the meantime, Xen does have proper default/max featuresets, and xen-cpuid
can even get them via the XEN_SYSCTL_cpu_policy_* interface, but only knows
now to render them nicely via the featureset interface.

Differences between default and max are a frequent source of errors,
frequently too in secret leading up to an embargo, so extend the featureset
sysctl to allow xen-cpuid to render them all nicely.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Christian Lindig <christian.lindig@cloud.com>
(cherry picked from commit 433d012c6c2737ad5a9aaa994355a4140d601852)

diff --git a/tools/misc/xen-cpuid.c b/tools/misc/xen-cpuid.c
index e774a9950ebbec42f391645c3429eeeb5310320d..859345ae8ab23d06e90d35269a138bfd0224a089 100644 (file)
--- a/tools/misc/xen-cpuid.c
+++ b/tools/misc/xen-cpuid.c
@@ -245,10 +245,12 @@ static const struct {
 #define COL_ALIGN "18"
 
 static const char *const fs_names[] = {
-    [XEN_SYSCTL_cpu_featureset_host] = "Host",
-    [XEN_SYSCTL_cpu_featureset_raw]  = "Raw",
-    [XEN_SYSCTL_cpu_featureset_pv]   = "PV",
-    [XEN_SYSCTL_cpu_featureset_hvm]  = "HVM",
+    [XEN_SYSCTL_cpu_featureset_raw]     = "Raw",
+    [XEN_SYSCTL_cpu_featureset_host]    = "Host",
+    [XEN_SYSCTL_cpu_featureset_pv]      = "PV Default",
+    [XEN_SYSCTL_cpu_featureset_hvm]     = "HVM Default",
+    [XEN_SYSCTL_cpu_featureset_pv_max]  = "PV Max",
+    [XEN_SYSCTL_cpu_featureset_hvm_max] = "HVM Max",
 };
 
 static void dump_leaf(uint32_t leaf, const char *const *strs)

diff --git a/tools/ocaml/libs/xc/xenctrl.ml b/tools/ocaml/libs/xc/xenctrl.ml
index aa650533f718fe41e2cfbe32189e3708dc3b42da..49aa9102f50339857b3f49083278250fe15609b4 100644 (file)
--- a/tools/ocaml/libs/xc/xenctrl.ml
+++ b/tools/ocaml/libs/xc/xenctrl.ml
@@ -309,7 +309,13 @@ external version_changeset: handle -> string = "stub_xc_version_changeset"
 external version_capabilities: handle -> string =
   "stub_xc_version_capabilities"
 
-type featureset_index = Featureset_raw | Featureset_host | Featureset_pv | Featureset_hvm
+type featureset_index =
+  | Featureset_raw
+  | Featureset_host
+  | Featureset_pv
+  | Featureset_hvm
+  | Featureset_pv_max
+  | Featureset_hvm_max
 external get_cpu_featureset : handle -> featureset_index -> int64 array = "stub_xc_get_cpu_featureset"
 
 external watchdog : handle -> int -> int32 -> int

diff --git a/tools/ocaml/libs/xc/xenctrl.mli b/tools/ocaml/libs/xc/xenctrl.mli
index 5bf5f5dfea36a54c0e6453b98b9f0f3e5ee87646..b9b92741296de4751a47c85c953e5c96dc81be28 100644 (file)
--- a/tools/ocaml/libs/xc/xenctrl.mli
+++ b/tools/ocaml/libs/xc/xenctrl.mli
@@ -235,7 +235,13 @@ external version_changeset : handle -> string = "stub_xc_version_changeset"
 external version_capabilities : handle -> string
   = "stub_xc_version_capabilities"
 
-type featureset_index = Featureset_raw | Featureset_host | Featureset_pv | Featureset_hvm
+type featureset_index =
+  | Featureset_raw
+  | Featureset_host
+  | Featureset_pv
+  | Featureset_hvm
+  | Featureset_pv_max
+  | Featureset_hvm_max
 external get_cpu_featureset : handle -> featureset_index -> int64 array = "stub_xc_get_cpu_featureset"
 
 external pages_to_kib : int64 -> int64 = "stub_pages_to_kib"

diff --git a/xen/arch/x86/sysctl.c b/xen/arch/x86/sysctl.c
index f8f8d797557e7afd1b5e3e0170bf5e254865d51e..d6612a17078d701c04869ac34bc37b94499d2d9c 100644 (file)
--- a/xen/arch/x86/sysctl.c
+++ b/xen/arch/x86/sysctl.c
@@ -327,14 +327,16 @@ long arch_do_sysctl(
 
     case XEN_SYSCTL_get_cpu_featureset:
     {
-        static const struct cpuid_policy *const policy_table[4] = {
+        static const struct cpuid_policy *const policy_table[6] = {
             [XEN_SYSCTL_cpu_featureset_raw]  = &raw_cpuid_policy,
             [XEN_SYSCTL_cpu_featureset_host] = &host_cpuid_policy,
 #ifdef CONFIG_PV
             [XEN_SYSCTL_cpu_featureset_pv]   = &pv_def_cpuid_policy,
+            [XEN_SYSCTL_cpu_featureset_pv_max] = &pv_max_cpuid_policy,
 #endif
 #ifdef CONFIG_HVM
             [XEN_SYSCTL_cpu_featureset_hvm]  = &hvm_def_cpuid_policy,
+            [XEN_SYSCTL_cpu_featureset_hvm_max] = &hvm_max_cpuid_policy,
 #endif
         };
         const struct cpuid_policy *p = NULL;

diff --git a/xen/include/public/sysctl.h b/xen/include/public/sysctl.h
index 001a4de27375ae64c7e3e9f0cc76aae1ca26664a..e8dded9fb94af0d089db229f79f3b717b77e859b 100644 (file)
--- a/xen/include/public/sysctl.h
+++ b/xen/include/public/sysctl.h
@@ -796,6 +796,8 @@ struct xen_sysctl_cpu_featureset {
 #define XEN_SYSCTL_cpu_featureset_host     1
 #define XEN_SYSCTL_cpu_featureset_pv       2
 #define XEN_SYSCTL_cpu_featureset_hvm      3
+#define XEN_SYSCTL_cpu_featureset_pv_max   4
+#define XEN_SYSCTL_cpu_featureset_hvm_max  5
     uint32_t index;       /* IN: Which featureset to query? */
     uint32_t nr_features; /* IN/OUT: Number of entries in/written to
                            * 'features', or the maximum number of features if