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x86: Clean up cr4 manipulation

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CR4 manipulation was split, seemingly at random, between direct
(write_cr4) and using a helper (set/clear_in_cr4).  Unfortunately,
the set_in_cr4 and clear_in_cr4 helpers also poke at the boot code,
which only a small subset of users actually wanted.

This patch replaces all cr4 access in functions that don't leave cr4
exactly the way they found it with new helpers cr4_set_bits,
cr4_clear_bits, and cr4_set_bits_and_update_boot.

Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Vince Weaver <vince@deater.net>
Cc: "hillf.zj" <hillf.zj@alibaba-inc.com>
Cc: Valdis Kletnieks <Valdis.Kletnieks@vt.edu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/495a10bdc9e67016b8fd3945700d46cfd5c12c2f.1414190806.git.luto@amacapital.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This commit is contained in:
Andy Lutomirski
2014-10-24 15:58:07 -07:00
committed by Ingo Molnar
parent 0967160ad6
commit 375074cc73
15 changed files with 70 additions and 57 deletions
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3
arch/x86/include/asm/virtext.h
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@@ -19,6 +19,7 @@
#include <asm/vmx.h>
#include <asm/svm.h>
#include <asm/tlbflush.h>
/*
* VMX functions:
@@ -40,7 +41,7 @@ static inline int cpu_has_vmx(void)
static inline void cpu_vmxoff(void)
{
asm volatile (ASM_VMX_VMXOFF : : : "cc");
write_cr4(read_cr4() & ~X86_CR4_VMXE);
cr4_clear_bits(X86_CR4_VMXE);
}
static inline int cpu_vmx_enabled(void)