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authorIngo Molnar <mingo@kernel.org>2015-04-30 09:09:26 +0200
committerIngo Molnar <mingo@kernel.org>2015-05-19 15:48:03 +0200
commit5e907bb0459399b0d1cc8d4c7e9f363a995b748a (patch)
tree7a0ba64607b1e538740ef6f5d6b95a91c80418fc /arch/x86/kernel/alternative.c
parentx86/fpu: Better document fpu__clear() state handling (diff)
downloadlinux-5e907bb0459399b0d1cc8d4c7e9f363a995b748a.tar.xz
linux-5e907bb0459399b0d1cc8d4c7e9f363a995b748a.zip
x86/alternatives, x86/fpu: Add 'alternatives_patched' debug flag and use it in xsave_state()
We'd like to use xsave_state() earlier, but its SYSTEM_BOOTING check is too imprecise. The real condition that xsave_state() would like to check is whether alternative XSAVE instructions were patched into the kernel image already. Add such a (read-mostly) debug flag and use it in xsave_state(). Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'arch/x86/kernel/alternative.c')
-rw-r--r--arch/x86/kernel/alternative.c5
1 files changed, 5 insertions, 0 deletions
diff --git a/arch/x86/kernel/alternative.c b/arch/x86/kernel/alternative.c
index aef653193160..7fe097235376 100644
--- a/arch/x86/kernel/alternative.c
+++ b/arch/x86/kernel/alternative.c
@@ -21,6 +21,10 @@
#include <asm/io.h>
#include <asm/fixmap.h>
+int __read_mostly alternatives_patched;
+
+EXPORT_SYMBOL_GPL(alternatives_patched);
+
#define MAX_PATCH_LEN (255-1)
static int __initdata_or_module debug_alternative;
@@ -627,6 +631,7 @@ void __init alternative_instructions(void)
apply_paravirt(__parainstructions, __parainstructions_end);
restart_nmi();
+ alternatives_patched = 1;
}
/**