diff options
author | Andy Lutomirski <luto@kernel.org> | 2016-10-31 23:18:43 +0100 |
---|---|---|
committer | Ingo Molnar <mingo@kernel.org> | 2016-11-01 07:47:53 +0100 |
commit | fc560a80bac91e512fc37cdfe03a982ef4543c6b (patch) | |
tree | 6ee04f275c4236a9324793df05ba07806cd0584e /arch | |
parent | x86/fpu: Get rid of two redundant clts() calls (diff) | |
download | linux-fc560a80bac91e512fc37cdfe03a982ef4543c6b.tar.xz linux-fc560a80bac91e512fc37cdfe03a982ef4543c6b.zip |
x86/fpu: Stop saving and restoring CR0.TS in fpu__init_check_bugs()
fpu__init_check_bugs() runs long after the early FPU init, so CR0.TS
will be clear by the time it runs. The save-and-restore dance would
have been unnecessary anyway, though, as kernel_fpu_begin() would
have been good enough.
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Quentin Casasnovas <quentin.casasnovas@oracle.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: kvm list <kvm@vger.kernel.org>
Link: http://lkml.kernel.org/r/76d1f1eacb5caead98197d1eb50ac6110ab20c6a.1477951965.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'arch')
-rw-r--r-- | arch/x86/kernel/fpu/bugs.c | 7 |
1 files changed, 0 insertions, 7 deletions
diff --git a/arch/x86/kernel/fpu/bugs.c b/arch/x86/kernel/fpu/bugs.c index aad34aafc0e0..d913047f832c 100644 --- a/arch/x86/kernel/fpu/bugs.c +++ b/arch/x86/kernel/fpu/bugs.c @@ -23,17 +23,12 @@ static double __initdata y = 3145727.0; */ void __init fpu__init_check_bugs(void) { - u32 cr0_saved; s32 fdiv_bug; /* kernel_fpu_begin/end() relies on patched alternative instructions. */ if (!boot_cpu_has(X86_FEATURE_FPU)) return; - /* We might have CR0::TS set already, clear it: */ - cr0_saved = read_cr0(); - write_cr0(cr0_saved & ~X86_CR0_TS); - kernel_fpu_begin(); /* @@ -56,8 +51,6 @@ void __init fpu__init_check_bugs(void) kernel_fpu_end(); - write_cr0(cr0_saved); - if (fdiv_bug) { set_cpu_bug(&boot_cpu_data, X86_BUG_FDIV); pr_warn("Hmm, FPU with FDIV bug\n"); |