diff options
| author | Andy Lutomirski <luto@kernel.org> | 2016-09-28 22:34:14 +0300 |
|---|---|---|
| committer | Sasha Levin <alexander.levin@verizon.com> | 2016-12-23 17:41:34 +0300 |
| commit | 0e3f4b0fd5f8031d56251a452630a3448133895c (patch) | |
| tree | 6d8ed47ccfc996a6e95b0d16a9867d61a0c7867a /arch | |
| parent | d884eb7cb82c974de5c8282c06b08edd1d0f2712 (diff) | |
| download | linux-0e3f4b0fd5f8031d56251a452630a3448133895c.tar.xz | |
x86/init: Fix cr4_init_shadow() on CR4-less machines
[ Upstream commit e1bfc11c5a6f40222a698a818dc269113245820e ]
cr4_init_shadow() will panic on 486-like machines without CR4. Fix
it using __read_cr4_safe().
Reported-by: david@saggiorato.net
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Reviewed-by: Borislav Petkov <bp@suse.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Fixes: 1e02ce4cccdc ("x86: Store a per-cpu shadow copy of CR4")
Link: http://lkml.kernel.org/r/43a20f81fb504013bf613913dc25574b45336a61.1475091074.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/x86/include/asm/tlbflush.h | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/arch/x86/include/asm/tlbflush.h b/arch/x86/include/asm/tlbflush.h index cd791948b286..7e459b7ee708 100644 --- a/arch/x86/include/asm/tlbflush.h +++ b/arch/x86/include/asm/tlbflush.h @@ -32,7 +32,7 @@ DECLARE_PER_CPU_SHARED_ALIGNED(struct tlb_state, cpu_tlbstate); /* Initialize cr4 shadow for this CPU. */ static inline void cr4_init_shadow(void) { - this_cpu_write(cpu_tlbstate.cr4, __read_cr4()); + this_cpu_write(cpu_tlbstate.cr4, __read_cr4_safe()); } /* Set in this cpu's CR4. */ |