]> git.ipfire.org Git - thirdparty/kernel/stable.git/commit
x86/fpu: Fix 'no387' regression
authorAndy Lutomirski <luto@kernel.org>
Thu, 21 Jan 2016 23:24:31 +0000 (15:24 -0800)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Sat, 16 Jun 2018 07:54:25 +0000 (09:54 +0200)
commit0e005aa5597ca9759954ea8131fe139f2f53c1f6
tree6a631e4002e270c5359ffbe92a6348c144712456
parent1d9af7dc0cd4d46bc34ac8656373188d8991f13c
x86/fpu: Fix 'no387' regression

commit f363938c70a04e6bc99023a5e0c44ef7879b903f upstream.

After fixing FPU option parsing, we now parse the 'no387' boot option
too early: no387 clears X86_FEATURE_FPU before it's even probed, so
the boot CPU promptly re-enables it.

I suspect it gets even more confused on SMP.

Fix the probing code to leave X86_FEATURE_FPU off if it's been
disabled by setup_clear_cpu_cap().

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Andy Lutomirski <luto@amacapital.net>
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: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Quentin Casasnovas <quentin.casasnovas@oracle.com>
Cc: Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: yu-cheng yu <yu-cheng.yu@intel.com>
Fixes: 4f81cbafcce2 ("x86/fpu: Fix early FPU command-line parsing")
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
arch/x86/kernel/fpu/init.c