File xsa435-0-17.patch of Package xen.31430

From 433d012c6c2737ad5a9aaa994355a4140d601852 Mon Sep 17 00:00:00 2001
From: Andrew Cooper <andrew.cooper3@citrix.com>
Date: Fri, 10 Mar 2023 19:37:56 +0000
Subject: 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>

--- a/tools/misc/xen-cpuid.c
+++ b/tools/misc/xen-cpuid.c
@@ -233,10 +233,12 @@ 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)
--- a/tools/ocaml/libs/xc/xenctrl.ml
+++ b/tools/ocaml/libs/xc/xenctrl.ml
@@ -281,7 +281,13 @@ external version_changeset: handle -> st
 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
--- a/tools/ocaml/libs/xc/xenctrl.mli
+++ b/tools/ocaml/libs/xc/xenctrl.mli
@@ -212,7 +212,13 @@ external version_changeset : handle -> s
 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"
--- a/xen/arch/x86/sysctl.c
+++ b/xen/arch/x86/sysctl.c
@@ -364,6 +364,8 @@ long arch_do_sysctl(
             [XEN_SYSCTL_cpu_featureset_host] = &host_cpuid_policy,
             [XEN_SYSCTL_cpu_featureset_pv]   = &pv_max_cpuid_policy,
             [XEN_SYSCTL_cpu_featureset_hvm]  = &hvm_max_cpuid_policy,
+            [XEN_SYSCTL_cpu_featureset_pv_max]  = &pv_max_cpuid_policy,
+            [XEN_SYSCTL_cpu_featureset_hvm_max] = &hvm_max_cpuid_policy,
         };
         const struct cpuid_policy *p = NULL;
         uint32_t featureset[FSCAPINTS];
--- a/xen/include/public/sysctl.h
+++ b/xen/include/public/sysctl.h
@@ -802,6 +802,8 @@ 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