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From: Borislav Petkov <bp@alien8.de>
To: X86 ML <x86@kernel.org>
Cc: LKML <linux-kernel@vger.kernel.org>
Subject: [PATCH v1 07/12] x86, copy_user_64.S: Convert to ALTERNATIVE_2
Date: Tue,  3 Feb 2015 19:16:25 +0100	[thread overview]
Message-ID: <1422987390-17878-8-git-send-email-bp@alien8.de> (raw)
In-Reply-To: <1422987390-17878-1-git-send-email-bp@alien8.de>

From: Borislav Petkov <bp@suse.de>

Use the asm macro and drop the locally grown version.

Signed-off-by: Borislav Petkov <bp@suse.de>
---
 arch/x86/lib/copy_user_64.S | 40 ++++++++++------------------------------
 1 file changed, 10 insertions(+), 30 deletions(-)

diff --git a/arch/x86/lib/copy_user_64.S b/arch/x86/lib/copy_user_64.S
index 4e6121ab5456..fa997dfaef24 100644
--- a/arch/x86/lib/copy_user_64.S
+++ b/arch/x86/lib/copy_user_64.S
@@ -16,30 +16,6 @@
 #include <asm/asm.h>
 #include <asm/smap.h>
 
-/*
- * By placing feature2 after feature1 in altinstructions section, we logically
- * implement:
- * If CPU has feature2, jmp to alt2 is used
- * else if CPU has feature1, jmp to alt1 is used
- * else jmp to orig is used.
- */
-	.macro ALTERNATIVE_JUMP feature1,feature2,orig,alt1,alt2
-0:
-	jmp \orig
-1:
-	.section .altinstr_replacement,"ax"
-2:
-	jmp \alt1
-3:
-	jmp \alt2
-	.previous
-
-	.section .altinstructions,"a"
-	altinstruction_entry 0b,2b,\feature1,5,5
-	altinstruction_entry 0b,3b,\feature2,5,5
-	.previous
-	.endm
-
 	.macro ALIGN_DESTINATION
 	/* check for bad alignment of destination */
 	movl %edi,%ecx
@@ -73,9 +49,11 @@ ENTRY(_copy_to_user)
 	jc bad_to_user
 	cmpq TI_addr_limit(%rax),%rcx
 	ja bad_to_user
-	ALTERNATIVE_JUMP X86_FEATURE_REP_GOOD,X86_FEATURE_ERMS,	\
-		copy_user_generic_unrolled,copy_user_generic_string,	\
-		copy_user_enhanced_fast_string
+	ALTERNATIVE_2 "jmp copy_user_generic_unrolled",		\
+		      "jmp copy_user_generic_string",		\
+		      X86_FEATURE_REP_GOOD,			\
+		      "jmp copy_user_enhanced_fast_string",	\
+		      X86_FEATURE_ERMS
 	CFI_ENDPROC
 ENDPROC(_copy_to_user)
 
@@ -88,9 +66,11 @@ ENTRY(_copy_from_user)
 	jc bad_from_user
 	cmpq TI_addr_limit(%rax),%rcx
 	ja bad_from_user
-	ALTERNATIVE_JUMP X86_FEATURE_REP_GOOD,X86_FEATURE_ERMS,	\
-		copy_user_generic_unrolled,copy_user_generic_string,	\
-		copy_user_enhanced_fast_string
+	ALTERNATIVE_2 "jmp copy_user_generic_unrolled",		\
+		      "jmp copy_user_generic_string",		\
+		      X86_FEATURE_REP_GOOD,			\
+		      "jmp copy_user_enhanced_fast_string",	\
+		      X86_FEATURE_ERMS
 	CFI_ENDPROC
 ENDPROC(_copy_from_user)
 
-- 
2.2.0.33.gc18b867


  parent reply	other threads:[~2015-02-03 18:19 UTC|newest]

Thread overview: 21+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-02-03 18:16 [PATCH v1 00/12] x86, alternatives: Instruction padding and more robust JMPs Borislav Petkov
2015-02-03 18:16 ` [PATCH v1 01/12] x86, copy_user: Remove FIX_ALIGNMENT define Borislav Petkov
2015-02-03 18:16 ` [PATCH v1 02/12] x86, alternatives: Cleanup DPRINTK macro Borislav Petkov
2015-02-03 19:01   ` Joe Perches
2015-02-03 18:16 ` [PATCH v1 03/12] x86, alternatives: Add instruction padding Borislav Petkov
2015-02-03 18:16 ` [PATCH v1 04/12] x86, alternatives: Make JMPs more robust Borislav Petkov
2015-02-03 18:16 ` [PATCH v1 05/12] x86, alternatives: Use optimized NOPs for padding Borislav Petkov
2015-02-03 19:36   ` Andy Lutomirski
2015-02-03 19:54     ` Borislav Petkov
2015-02-03 18:16 ` [PATCH v1 06/12] x86, copy_page_64.S: Use generic ALTERNATIVE macro Borislav Petkov
2015-02-03 18:16 ` Borislav Petkov [this message]
2015-02-03 18:16 ` [PATCH v1 08/12] x86, SMAP: Use " Borislav Petkov
2015-02-03 18:16 ` [PATCH v1 09/12] x86, alternative: Convert X86_INVD_BUG to generic macro Borislav Petkov
2015-02-03 18:16 ` [PATCH v1 10/12] x86, alternatives: Convert clear_page_64.S Borislav Petkov
2015-02-03 18:16 ` [PATCH v1 11/12] x86, alternative: Use alternative_2 in rdtsc_barrier Borislav Petkov
2015-02-03 19:55   ` Andy Lutomirski
2015-02-03 20:08     ` Borislav Petkov
2015-02-03 18:16 ` [PATCH v1 12/12] x86, alternative: Cleanup prefetch primitives Borislav Petkov
2015-02-18 21:20 ` [PATCH v1 00/12] x86, alternatives: Instruction padding and more robust JMPs Ingo Molnar
2015-02-18 21:23   ` Borislav Petkov
2015-02-24 11:04   ` Borislav Petkov

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