x86: properly gate clearing of PKU feature

setup_clear_cpu_cap() is __init and hence may not be called post-boot.
Note that opt_pku nevertheless is not getting __initdata added - see
e.g. commit 43fa95ae6a ("mm: make opt_bootscrub non-init").

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
master commit: 41c7700a00011ad08be3c9d71126b67e08e58ac3
master date: 2019-08-29 15:10:07 +0200

diff --git a/xen/arch/x86/cpu/common.c b/xen/arch/x86/cpu/common.c
index e438191c369e5b15c9dc2b5075095bc1379b74d8..b40c45d0971951c6e11f188e2d064da72f9923e3 100644 (file)
--- a/xen/arch/x86/cpu/common.c
+++ b/xen/arch/x86/cpu/common.c
@@ -472,7 +472,7 @@ void identify_cpu(struct cpuinfo_x86 *c)
                this_cpu->c_init(c);
 
 
-       if ( !opt_pku )
+       if (c == &boot_cpu_data && !opt_pku)
                setup_clear_cpu_cap(X86_FEATURE_PKU);
 
        /*