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From: Martin Schwidefsky <schwidefsky@de.ibm.com>
To: linux-kernel@vger.kernel.org, linux-s390@vger.kernel.org
Cc: Bastian Blank <bastian@waldi.eu.org>,
	Heiko Carstens <heiko.carstens@de.ibm.com>,
	Martin Schwidefsky <schwidefsky@de.ibm.com>
Subject: [patch 03/10] Get rid of memcpy gcc warning workaround.
Date: Wed, 05 Mar 2008 12:54:35 +0100	[thread overview]
Message-ID: <20080305115713.586405448@de.ibm.com> (raw)
In-Reply-To: <20080305115432.691030908@de.ibm.com>

[-- Attachment #1: 003-memcpy-warning.diff --]
[-- Type: text/plain, Size: 2065 bytes --]

From: Heiko Carstens <heiko.carstens@de.ibm.com>

Compile smp.o with -Wno-nonnull so gcc stops warning about memcpy
being used with a null parameter. Also remove the workaround code
and use a char * cast instead of a void * cast to do computations.

Cc: Bastian Blank <bastian@waldi.eu.org>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
---

 arch/s390/kernel/Makefile |    5 +++++
 arch/s390/kernel/smp.c    |   10 ++--------
 2 files changed, 7 insertions(+), 8 deletions(-)

Index: quilt-2.6/arch/s390/kernel/Makefile
===================================================================
--- quilt-2.6.orig/arch/s390/kernel/Makefile
+++ quilt-2.6/arch/s390/kernel/Makefile
@@ -4,6 +4,11 @@
 
 EXTRA_AFLAGS	:= -traditional
 
+#
+# Passing null pointers is ok for smp code, since we access the lowcore here.
+#
+CFLAGS_smp.o	:= -Wno-nonnull
+
 obj-y	:=  bitmap.o traps.o time.o process.o base.o early.o \
             setup.o sys_s390.o ptrace.o signal.o cpcmd.o ebcdic.o \
 	    semaphore.o s390_ext.o debug.o irq.o ipl.o dis.o diag.o
Index: quilt-2.6/arch/s390/kernel/smp.c
===================================================================
--- quilt-2.6.orig/arch/s390/kernel/smp.c
+++ quilt-2.6/arch/s390/kernel/smp.c
@@ -629,14 +629,8 @@ static int __cpuinit smp_alloc_lowcore(i
 	panic_stack = __get_free_page(GFP_KERNEL);
 	if (!panic_stack || !async_stack)
 		goto out;
-	/*
-	 * Only need to copy the first 512 bytes from address 0. But since
-	 * the compiler emits a warning if src == NULL for memcpy use copy_page
-	 * instead. Copies more than needed but this code is not performance
-	 * critical.
-	 */
-	copy_page(lowcore, &S390_lowcore);
-	memset((void *)lowcore + 512, 0, sizeof(*lowcore) - 512);
+	memcpy(lowcore, &S390_lowcore, 512);
+	memset((char *)lowcore + 512, 0, sizeof(*lowcore) - 512);
 	lowcore->async_stack = async_stack + ASYNC_SIZE;
 	lowcore->panic_stack = panic_stack + PAGE_SIZE;
 

-- 
blue skies,
   Martin.

"Reality continues to ruin my life." - Calvin.


  parent reply	other threads:[~2008-03-05 12:01 UTC|newest]

Thread overview: 11+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2008-03-05 11:54 [patch 00/10] s390 bux fixes for 2.6.25-rc4 Martin Schwidefsky
2008-03-05 11:54 ` [patch 01/10] Update default configuration Martin Schwidefsky
2008-03-05 11:54 ` [patch 02/10] idle: Fix machine check handling in idle loop Martin Schwidefsky
2008-03-05 11:54 ` Martin Schwidefsky [this message]
2008-03-05 11:54 ` [patch 04/10] dasd: let dasd erp matching recognize alias recovery Martin Schwidefsky
2008-03-05 11:54 ` [patch 05/10] dasd: fix reference counting in display method for proc/dasd/devices Martin Schwidefsky
2008-03-05 11:54 ` [patch 06/10] sclp_vt220: speed up console output for interactive work Martin Schwidefsky
2008-03-05 11:54 ` [patch 07/10] zcrypt: fix ap_device_list handling Martin Schwidefsky
2008-03-05 11:54 ` [patch 08/10] Fix IPL from NSS Martin Schwidefsky
2008-03-05 11:54 ` [patch 09/10] Load disabled wait psw if reipl fails Martin Schwidefsky
2008-03-05 11:54 ` [patch 10/10] incorrect reipl nss name Martin Schwidefsky

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