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| author | Andy Lutomirski <luto@kernel.org> | 2016-09-29 21:48:11 +0200 |
|---|---|---|
| committer | Thomas Gleixner <tglx@linutronix.de> | 2016-09-30 12:37:40 +0200 |
| commit | 192d1dccbfc5b901b66527df9df80304693cf06e (patch) | |
| tree | 8ee15ef8ca5f7bc9887dbd61f66c171013c4aae5 /arch/x86/kernel/setup.c | |
| parent | x86/init: Fix cr4_init_shadow() on CR4-less machines (diff) | |
| download | linux-192d1dccbfc5b901b66527df9df80304693cf06e.tar.xz linux-192d1dccbfc5b901b66527df9df80304693cf06e.zip | |
x86/boot: Fix another __read_cr4() case on 486
The condition for reading CR4 was wrong: there are some CPUs with
CPUID but not CR4. Rather than trying to make the condition exact,
use __read_cr4_safe().
Fixes: 18bc7bd523e0 ("x86/boot: Synchronize trampoline_cr4_features and mmu_cr4_features directly")
Reported-by: david@saggiorato.net
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Reviewed-by: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Link: http://lkml.kernel.org/r/8c453a61c4f44ab6ff43c29780ba04835234d2e5.1475178369.git.luto@kernel.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Diffstat (limited to 'arch/x86/kernel/setup.c')
| -rw-r--r-- | arch/x86/kernel/setup.c | 4 |
1 files changed, 1 insertions, 3 deletions
diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c index 0fa60f5f5a16..98c9cd6f3b5d 100644 --- a/arch/x86/kernel/setup.c +++ b/arch/x86/kernel/setup.c @@ -1137,9 +1137,7 @@ void __init setup_arch(char **cmdline_p) * auditing all the early-boot CR4 manipulation would be needed to * rule it out. */ - if (boot_cpu_data.cpuid_level >= 0) - /* A CPU has %cr4 if and only if it has CPUID. */ - mmu_cr4_features = __read_cr4(); + mmu_cr4_features = __read_cr4_safe(); memblock_set_current_limit(get_max_mapped()); |