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x86/cpu: Move X86_BUG_ESPFIX initialization to generic_identify() 

It was in detect_nopl(), which was either a mistake by me or some kind
of mis-merge.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Reviewed-by: Borislav Petkov <bp@suse.de>
Cc: Andy Lutomirski <luto@amacapital.net>
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: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rudolf Marek <r.marek@assembler.cz>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: ff236456f072 ("x86/cpu: Move X86_BUG_ESPFIX initialization to generic_identify")
Link: http://lkml.kernel.org/r/0949337f13660461edca08ab67d1a841441289c9.1460075211.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This commit is contained in:
Andy Lutomirski 2016-04-07 17:31:48 -07:00 committed by Ingo Molnar
parent 3e2b68d752
commit 0230bb038f
1 changed files with 25 additions and 25 deletions
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50
arch/x86/kernel/cpu/common.c
View File

@ -861,31 +861,6 @@ static void detect_nopl(struct cpuinfo_x86 *c)
clear_cpu_cap(c, X86_FEATURE_NOPL);
#else
set_cpu_cap(c, X86_FEATURE_NOPL);
#endif
/*
* ESPFIX is a strange bug. All real CPUs have it. Paravirt
* systems that run Linux at CPL > 0 may or may not have the
* issue, but, even if they have the issue, there's absolutely
* nothing we can do about it because we can't use the real IRET
* instruction.
*
* NB: For the time being, only 32-bit kernels support
* X86_BUG_ESPFIX as such. 64-bit kernels directly choose
* whether to apply espfix using paravirt hooks. If any
* non-paravirt system ever shows up that does *not* have the
* ESPFIX issue, we can change this.
*/
#ifdef CONFIG_X86_32
#ifdef CONFIG_PARAVIRT
do {
extern void native_iret(void);
if (pv_cpu_ops.iret == native_iret)
set_cpu_bug(c, X86_BUG_ESPFIX);
} while (0);
#else
set_cpu_bug(c, X86_BUG_ESPFIX);
#endif
#endif
}
@ -952,6 +927,31 @@ static void generic_identify(struct cpuinfo_x86 *c)
detect_nopl(c);
detect_null_seg_behavior(c);
/*
* ESPFIX is a strange bug. All real CPUs have it. Paravirt
* systems that run Linux at CPL > 0 may or may not have the
* issue, but, even if they have the issue, there's absolutely
* nothing we can do about it because we can't use the real IRET
* instruction.
*
* NB: For the time being, only 32-bit kernels support
* X86_BUG_ESPFIX as such. 64-bit kernels directly choose
* whether to apply espfix using paravirt hooks. If any
* non-paravirt system ever shows up that does *not* have the
* ESPFIX issue, we can change this.
*/
#ifdef CONFIG_X86_32
# ifdef CONFIG_PARAVIRT
do {
extern void native_iret(void);
if (pv_cpu_ops.iret == native_iret)
set_cpu_bug(c, X86_BUG_ESPFIX);
} while (0);
# else
set_cpu_bug(c, X86_BUG_ESPFIX);
# endif
#endif
}
static void x86_init_cache_qos(struct cpuinfo_x86 *c)