[Xen-devel] [PATCH 1/3] x86/amd: revert commit 944e0fc51a89c9827b9

[Juergen Gross <jgross@xxxxxxxx>]

Revert commit 944e0fc51a89c9827b98813d65dc083274777c7f ("x86/amd: don't
set X86_BUG_SYSRET_SS_ATTRS when running under Xen") as it is lacking
a prerequisite patch and is making things worse.

Signed-off-by: Juergen Gross <jgross@xxxxxxxx>
---
 arch/x86/kernel/cpu/amd.c | 5 ++---
 arch/x86/xen/enlighten.c  | 4 +++-
 2 files changed, 5 insertions(+), 4 deletions(-)

diff --git a/arch/x86/kernel/cpu/amd.c b/arch/x86/kernel/cpu/amd.c
index 4c2be99fa0fb..cd0abf8ed314 100644
--- a/arch/x86/kernel/cpu/amd.c
+++ b/arch/x86/kernel/cpu/amd.c
@@ -857,9 +857,8 @@ static void init_amd(struct cpuinfo_x86 *c)
                if (cpu_has(c, X86_FEATURE_3DNOW) || cpu_has(c, X86_FEATURE_LM))
                        set_cpu_cap(c, X86_FEATURE_3DNOWPREFETCH);
 
-       /* AMD CPUs don't reset SS attributes on SYSRET, Xen does. */
-       if (!cpu_has(c, X86_FEATURE_XENPV))
-               set_cpu_bug(c, X86_BUG_SYSRET_SS_ATTRS);
+       /* AMD CPUs don't reset SS attributes on SYSRET */
+       set_cpu_bug(c, X86_BUG_SYSRET_SS_ATTRS);
 }
 
 #ifdef CONFIG_X86_32
diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c
index 081437b5f381..2bea87cc0ff2 100644
--- a/arch/x86/xen/enlighten.c
+++ b/arch/x86/xen/enlighten.c
@@ -1977,8 +1977,10 @@ EXPORT_SYMBOL_GPL(xen_hvm_need_lapic);
 
 static void xen_set_cpu_features(struct cpuinfo_x86 *c)
 {
-       if (xen_pv_domain())
+       if (xen_pv_domain()) {
+               clear_cpu_bug(c, X86_BUG_SYSRET_SS_ATTRS);
                set_cpu_cap(c, X86_FEATURE_XENPV);
+       }
 }
 
 static void xen_pin_vcpu(int cpu)
-- 
2.13.6


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