[xen stable-4.12] libx86/CPUID: fix (not just) leaf 7 processing

[patchbot@xxxxxxx]

commit 736c67bc46a333b24a9b0ffc902768ab96505ad6
Author:     Jan Beulich <jbeulich@xxxxxxxx>
AuthorDate: Thu Apr 9 09:32:36 2020 +0200
Commit:     Jan Beulich <jbeulich@xxxxxxxx>
CommitDate: Thu Apr 9 09:32:36 2020 +0200

    libx86/CPUID: fix (not just) leaf 7 processing
    
    x86_cpuid_policy_fill_native() should, as it did originally, iterate
    over all subleaves here as well as over all main leaves. Switch to
    using a "<= MIN()"-based approach similar to that used in
    x86_cpuid_copy_to_buffer(). Also follow this for the extended main
    leaves then.
    
    Fixes: 1bd2b750537b ("libx86: Fix 32bit stubdom build of 
x86_cpuid_policy_fill_native()")
    Signed-off-by: Jan Beulich <jbeulich@xxxxxxxx>
    Reviewed-by: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
    master commit: eb0bad81fceb3e81df5f73441771b49b732edf56
    master date: 2020-03-27 11:40:59 +0100
---
 xen/lib/x86/cpuid.c | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/xen/lib/x86/cpuid.c b/xen/lib/x86/cpuid.c
index 5a3159b357..2e99e30dc9 100644
--- a/xen/lib/x86/cpuid.c
+++ b/xen/lib/x86/cpuid.c
@@ -7,8 +7,8 @@ void x86_cpuid_policy_fill_native(struct cpuid_policy *p)
     unsigned int i;
 
     cpuid_leaf(0, &p->basic.raw[0]);
-    for ( i = 1; i < min_t(unsigned int, ARRAY_SIZE(p->basic.raw),
-                           p->basic.max_leaf); ++i )
+    for ( i = 1; i <= MIN(p->basic.max_leaf,
+                          ARRAY_SIZE(p->basic.raw) - 1); ++i )
     {
         switch ( i )
         {
@@ -52,8 +52,8 @@ void x86_cpuid_policy_fill_native(struct cpuid_policy *p)
     {
         cpuid_count_leaf(7, 0, &p->feat.raw[0]);
 
-        for ( i = 1; i < min_t(unsigned int, ARRAY_SIZE(p->feat.raw),
-                               p->feat.max_subleaf); ++i )
+        for ( i = 1; i <= MIN(p->feat.max_subleaf,
+                              ARRAY_SIZE(p->feat.raw) - 1); ++i )
             cpuid_count_leaf(7, i, &p->feat.raw[i]);
     }
 
@@ -106,8 +106,8 @@ void x86_cpuid_policy_fill_native(struct cpuid_policy *p)
 
     /* Extended leaves. */
     cpuid_leaf(0x80000000, &p->extd.raw[0]);
-    for ( i = 1; i < min_t(unsigned int, ARRAY_SIZE(p->extd.raw),
-                           p->extd.max_leaf + 1 - 0x80000000); ++i )
+    for ( i = 1; i <= MIN(p->extd.max_leaf & 0xffffU,
+                          ARRAY_SIZE(p->extd.raw) - 1); ++i )
         cpuid_leaf(0x80000000 + i, &p->extd.raw[i]);
 }
 
--
generated by git-patchbot for /home/xen/git/xen.git#stable-4.12