40 lines
1.7 KiB
Diff
40 lines
1.7 KiB
Diff
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From 8c8187d41b99acd4f2078d0fff6807e0eeb47407 Mon Sep 17 00:00:00 2001
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From: Arnd Bergmann <arnd@arndb.de>
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Date: Thu, 26 Jul 2018 10:13:23 +0200
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Subject: [PATCH] ARM: fix put_user() for gcc-8
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Building kernels before linux-4.7 with gcc-8 results in many build failures
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when gcc triggers a check that was meant to catch broken compilers:
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/tmp/ccCGMQmS.s:648: Error: .err encountered
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According to the discussion in the gcc bugzilla, a local "register
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asm()" variable is still supposed to be the correct way to force an
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inline assembly to use a particular register, but marking it 'const'
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lets the compiler do optimizations that break that, i.e the compiler is
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free to treat the variable as either 'const' or 'register' in that case.
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Upstream commit 9f73bd8bb445 ("ARM: uaccess: remove put_user() code
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duplication") fixed this problem in linux-4.8 as part of a larger change,
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but seems a little too big to be backported to 4.4.
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Let's take the simplest fix and change only the one broken line in the
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same way as newer kernels.
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Suggested-by: Bernd Edlinger <bernd.edlinger@hotmail.de>
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Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85745
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Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=86673
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Signed-off-by: Arnd Bergmann <arnd@arndb.de>
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Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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---
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arch/arm/include/asm/uaccess.h | 2 +-
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1 file changed, 1 insertion(+), 1 deletion(-)
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diff --git a/arch/arm/include/asm/uaccess.h b/arch/arm/include/asm/uaccess.h
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index b04850fdeb5..f8ad54b24ac 100644
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--- a/arch/arm/include/asm/uaccess.h
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+++ b/arch/arm/include/asm/uaccess.h
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@@ -162 +162 @@ extern int __put_user_8(void *, unsigned long long);
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- register const typeof(*(p)) __r2 asm("r2") = (x); \
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+ register typeof(*(p)) __r2 asm("r2") = (x); \
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