From: Peter Zijlstra <peterz@infradead.org>
To: David Woodhouse <dwmw2@infradead.org>,
Josh Poimboeuf <jpoimboe@redhat.com>
Cc: linux-kernel@vger.kernel.org, Dave Hansen <dave.hansen@intel.com>,
Ashok Raj <ashok.raj@intel.com>,
Thomas Gleixner <tglx@linutronix.de>,
Tim Chen <tim.c.chen@linux.intel.com>,
Andy Lutomirski <luto@kernel.org>,
Linus Torvalds <torvalds@linux-foundation.org>,
Greg KH <gregkh@linuxfoundation.org>,
Andrea Arcangeli <aarcange@redhat.com>,
Andi Kleen <ak@linux.intel.com>,
Arjan Van De Ven <arjan.van.de.ven@intel.com>,
Dan Williams <dan.j.williams@intel.com>,
Paolo Bonzini <pbonzini@redhat.com>,
Jun Nakajima <jun.nakajima@intel.com>,
Asit Mallick <asit.k.mallick@intel.com>,
Peter Zijlstra <peterz@infradead.org>
Subject: [PATCH v2 05/10] x86: Annotate static_cpu_has alternative
Date: Tue, 16 Jan 2018 15:28:30 +0100 [thread overview]
Message-ID: <20180116143241.176728634@infradead.org> (raw)
In-Reply-To: 20180116142825.376986833@infradead.org
[-- Attachment #1: peterz-x86-static_cpu_has-annotate.patch --]
[-- Type: text/plain, Size: 1696 bytes --]
In order to recognise static_cpu_has() alternatives from any other
alternative without dodgy heuristics, we need to explicitly mark them.
Use the new type field for this.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
---
arch/x86/include/asm/alternative.h | 1 +
arch/x86/include/asm/cpufeature.h | 5 +++--
2 files changed, 4 insertions(+), 2 deletions(-)
--- a/arch/x86/include/asm/alternative.h
+++ b/arch/x86/include/asm/alternative.h
@@ -46,6 +46,7 @@
#endif
#define ALT_TYPE_DEFAULT 0
+#define ALT_TYPE_STATIC_CPU_HAS 1 /* objtool, static_cpu_has */
struct alt_instr {
s32 instr_offset; /* original instruction */
--- a/arch/x86/include/asm/cpufeature.h
+++ b/arch/x86/include/asm/cpufeature.h
@@ -157,7 +157,7 @@ static __always_inline __pure bool _stat
" .byte 3b - 1b\n" /* src len */
" .byte 5f - 4f\n" /* repl len */
" .byte 3b - 2b\n" /* pad len */
- " .byte 0\n" /* type */
+ " .byte %P[type]\n" /* type */
".previous\n"
".section .altinstr_replacement,\"ax\"\n"
"4: jmp %l[t_no]\n"
@@ -170,7 +170,7 @@ static __always_inline __pure bool _stat
" .byte 3b - 1b\n" /* src len */
" .byte 0\n" /* repl len */
" .byte 0\n" /* pad len */
- " .byte 0\n" /* type */
+ " .byte %P[type]\n" /* type */
".previous\n"
".section .altinstr_aux,\"ax\"\n"
"6:\n"
@@ -181,6 +181,7 @@ static __always_inline __pure bool _stat
: : [feature] "i" (bit),
[always] "i" (X86_FEATURE_ALWAYS),
[bitnum] "i" (1 << (bit & 7)),
+ [type] "i" (ALT_TYPE_STATIC_CPU_HAS),
[cap_byte] "m" (((const char *)boot_cpu_data.x86_capability)[bit >> 3])
: : t_yes, t_no);
t_yes:
next prev parent reply other threads:[~2018-01-16 14:37 UTC|newest]
Thread overview: 34+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-01-16 14:28 [PATCH v2 00/10] objtool validation of static branches and retpoline Peter Zijlstra
2018-01-16 14:28 ` [PATCH v2 01/10] x86: Reindent _static_cpu_has Peter Zijlstra
2018-01-16 15:48 ` Borislav Petkov
2018-01-16 14:28 ` [PATCH v2 02/10] x86: Update _static_cpu_has to use all named variables Peter Zijlstra
2018-01-18 11:21 ` Borislav Petkov
2018-01-18 15:09 ` Peter Zijlstra
2018-01-18 15:24 ` Borislav Petkov
2018-01-16 14:28 ` [PATCH v2 03/10] x86: Add a type field to alt_instr Peter Zijlstra
2018-01-16 22:49 ` Josh Poimboeuf
2018-01-16 22:53 ` Borislav Petkov
2018-01-16 23:06 ` Josh Poimboeuf
2018-01-18 11:32 ` Borislav Petkov
2018-01-16 14:28 ` [PATCH v2 04/10] objtool: Implement base jump_assert support Peter Zijlstra
2018-01-16 14:28 ` Peter Zijlstra [this message]
2018-01-18 13:15 ` [PATCH v2 05/10] x86: Annotate static_cpu_has alternative Borislav Petkov
2018-01-16 14:28 ` [PATCH v2 06/10] objtool: Implement jump_assert for _static_cpu_has() Peter Zijlstra
2018-01-16 23:02 ` Josh Poimboeuf
2018-01-17 9:19 ` Peter Zijlstra
2018-01-17 14:27 ` Josh Poimboeuf
2018-01-17 14:30 ` Josh Poimboeuf
2018-01-17 16:30 ` Peter Zijlstra
2018-01-16 14:28 ` [PATCH v2 07/10] x86/jump_label: Implement arch_static_assert() Peter Zijlstra
2018-01-18 13:33 ` Borislav Petkov
2018-01-18 15:31 ` Peter Zijlstra
2018-01-16 14:28 ` [PATCH v2 08/10] objtool: Add retpoline validation Peter Zijlstra
2018-01-16 14:28 ` [PATCH v2 09/10] x86: Annotate dynamic jump in head_64.S Peter Zijlstra
2018-01-16 14:28 ` [PATCH v2 10/10] objtool: More complex static jump implementation Peter Zijlstra
2018-01-16 15:20 ` Peter Zijlstra
2018-01-17 3:05 ` Josh Poimboeuf
2018-01-17 8:18 ` Peter Zijlstra
2018-01-16 19:49 ` [PATCH v2 11/10] objtool: Even more complex static block checks Peter Zijlstra
2018-01-17 3:12 ` Josh Poimboeuf
2018-01-17 8:13 ` Peter Zijlstra
2018-01-17 14:13 ` Josh Poimboeuf
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