x86/amd: revert commit 944e0fc51a89c9827b9
authorJuergen Gross <jgross@suse.com>
Wed, 30 May 2018 11:09:56 +0000 (13:09 +0200)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Wed, 6 Jun 2018 14:44:34 +0000 (16:44 +0200)
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@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
arch/x86/kernel/cpu/amd.c
arch/x86/xen/enlighten.c

index 4c2be99..cd0abf8 100644 (file)
@@ -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
index e3a3f5a..b19ba66 100644 (file)
@@ -1980,8 +1980,10 @@ 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)