mirror of
https://github.com/AuxXxilium/linux_dsm_epyc7002.git
synced 2024-12-27 06:45:09 +07:00
ff05ab2305
To facillitate other usage of ignoring alternatives; rename ANNOTATE_NOSPEC_IGNORE to ANNOTATE_IGNORE_ALTERNATIVE. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Borislav Petkov <bp@alien8.de> 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> Signed-off-by: Ingo Molnar <mingo@kernel.org>
115 lines
2.7 KiB
C
115 lines
2.7 KiB
C
/* SPDX-License-Identifier: GPL-2.0 */
|
|
#ifndef _ASM_X86_ALTERNATIVE_ASM_H
|
|
#define _ASM_X86_ALTERNATIVE_ASM_H
|
|
|
|
#ifdef __ASSEMBLY__
|
|
|
|
#include <asm/asm.h>
|
|
|
|
#ifdef CONFIG_SMP
|
|
.macro LOCK_PREFIX
|
|
672: lock
|
|
.pushsection .smp_locks,"a"
|
|
.balign 4
|
|
.long 672b - .
|
|
.popsection
|
|
.endm
|
|
#else
|
|
.macro LOCK_PREFIX
|
|
.endm
|
|
#endif
|
|
|
|
/*
|
|
* objtool annotation to ignore the alternatives and only consider the original
|
|
* instruction(s).
|
|
*/
|
|
.macro ANNOTATE_IGNORE_ALTERNATIVE
|
|
.Lannotate_\@:
|
|
.pushsection .discard.ignore_alts
|
|
.long .Lannotate_\@ - .
|
|
.popsection
|
|
.endm
|
|
|
|
/*
|
|
* Issue one struct alt_instr descriptor entry (need to put it into
|
|
* the section .altinstructions, see below). This entry contains
|
|
* enough information for the alternatives patching code to patch an
|
|
* instruction. See apply_alternatives().
|
|
*/
|
|
.macro altinstruction_entry orig alt feature orig_len alt_len pad_len
|
|
.long \orig - .
|
|
.long \alt - .
|
|
.word \feature
|
|
.byte \orig_len
|
|
.byte \alt_len
|
|
.byte \pad_len
|
|
.endm
|
|
|
|
/*
|
|
* Define an alternative between two instructions. If @feature is
|
|
* present, early code in apply_alternatives() replaces @oldinstr with
|
|
* @newinstr. ".skip" directive takes care of proper instruction padding
|
|
* in case @newinstr is longer than @oldinstr.
|
|
*/
|
|
.macro ALTERNATIVE oldinstr, newinstr, feature
|
|
140:
|
|
\oldinstr
|
|
141:
|
|
.skip -(((144f-143f)-(141b-140b)) > 0) * ((144f-143f)-(141b-140b)),0x90
|
|
142:
|
|
|
|
.pushsection .altinstructions,"a"
|
|
altinstruction_entry 140b,143f,\feature,142b-140b,144f-143f,142b-141b
|
|
.popsection
|
|
|
|
.pushsection .altinstr_replacement,"ax"
|
|
143:
|
|
\newinstr
|
|
144:
|
|
.popsection
|
|
.endm
|
|
|
|
#define old_len 141b-140b
|
|
#define new_len1 144f-143f
|
|
#define new_len2 145f-144f
|
|
|
|
/*
|
|
* gas compatible max based on the idea from:
|
|
* http://graphics.stanford.edu/~seander/bithacks.html#IntegerMinOrMax
|
|
*
|
|
* The additional "-" is needed because gas uses a "true" value of -1.
|
|
*/
|
|
#define alt_max_short(a, b) ((a) ^ (((a) ^ (b)) & -(-((a) < (b)))))
|
|
|
|
|
|
/*
|
|
* Same as ALTERNATIVE macro above but for two alternatives. If CPU
|
|
* has @feature1, it replaces @oldinstr with @newinstr1. If CPU has
|
|
* @feature2, it replaces @oldinstr with @feature2.
|
|
*/
|
|
.macro ALTERNATIVE_2 oldinstr, newinstr1, feature1, newinstr2, feature2
|
|
140:
|
|
\oldinstr
|
|
141:
|
|
.skip -((alt_max_short(new_len1, new_len2) - (old_len)) > 0) * \
|
|
(alt_max_short(new_len1, new_len2) - (old_len)),0x90
|
|
142:
|
|
|
|
.pushsection .altinstructions,"a"
|
|
altinstruction_entry 140b,143f,\feature1,142b-140b,144f-143f,142b-141b
|
|
altinstruction_entry 140b,144f,\feature2,142b-140b,145f-144f,142b-141b
|
|
.popsection
|
|
|
|
.pushsection .altinstr_replacement,"ax"
|
|
143:
|
|
\newinstr1
|
|
144:
|
|
\newinstr2
|
|
145:
|
|
.popsection
|
|
.endm
|
|
|
|
#endif /* __ASSEMBLY__ */
|
|
|
|
#endif /* _ASM_X86_ALTERNATIVE_ASM_H */
|