Re: [PATCH] linkage.h: fix build breakage due to symbol prefixhandling

From: Stephen Rothwell
Date: Wed May 01 2013 - 23:38:12 EST


Hi all,

On Thu, 02 May 2013 09:58:08 +0930 Rusty Russell <rusty@xxxxxxxxxxxxxxx> wrote:
>
> James Hogan <james.hogan@xxxxxxxxxx> writes:
> > Al's commit e1b5bb6d1236d4ad2084c53aa83dde7cdf6f8eea ("consolidate
> > cond_syscall and SYSCALL_ALIAS declarations") broke the build on
> > blackfin and metag due to the following code:
> >
> > #ifndef SYMBOL_NAME
> > #ifdef CONFIG_SYMBOL_PREFIX
> > #define SYMBOL_NAME(x) CONFIG_SYMBOL_PREFIX ## x
> > #else
> > #define SYMBOL_NAME(x) x
> > #endif
> > #endif
> > #define __SYMBOL_NAME(x) __stringify(SYMBOL_NAME(x))
> >
> > __stringify literally stringifies CONFIG_SYMBOL_PREFIX ##x, so you get
> > lines like this in kernel/sys_ni.s:
> >
> > .weak CONFIG_SYMBOL_PREFIXsys_quotactl
> > .set CONFIG_SYMBOL_PREFIXsys_quotactl,CONFIG_SYMBOL_PREFIXsys_ni_syscall
> >
> > The patches in Rusty's modules-next tree such as "CONFIG_SYMBOL_PREFIX:
> > cleanup." clean up the whole mess around symbol prefixes, so this patch
> > just attempts to fix the build in the mean time. The intermediate
> > definition of SYMBOL_NAME above isn't used and is incorrect when
> > CONFIG_SYMBOL_PREFIX is defined as CONFIG_SYMBOL_PREFIX is a quoted
> > string literal, so define __SYMBOL_NAME directly depending on
> > CONFIG_SYMBOL_PREFIX.
>
> I just pushed my modules-next tree to Linus, so hopefully the nightmare
> is over soon!

This is the merge fix patch I have been carrying in linux-next since
March 14: (this probably does not quite apply any more but, hey ...)

From: Stephen Rothwell <sfr@xxxxxxxxxxxxxxxx>
Date: Thu, 14 Mar 2013 17:14:41 +1100
Subject: [PATCH] cond_syscall and SYSCALL_ALIAS merge fixup

Signed-off-by: Stephen Rothwell <sfr@xxxxxxxxxxxxxxxx>
---
include/linux/linkage.h | 20 ++++++--------------
1 file changed, 6 insertions(+), 14 deletions(-)

diff --git a/include/linux/linkage.h b/include/linux/linkage.h
index 829d66c..bedcddf 100644
--- a/include/linux/linkage.h
+++ b/include/linux/linkage.h
@@ -2,7 +2,7 @@
#define _LINUX_LINKAGE_H

#include <linux/compiler.h>
-#include <linux/stringify.h>
+#include <linux/export.h>
#include <asm/linkage.h>

#ifdef __cplusplus
@@ -15,24 +15,16 @@
#define asmlinkage CPP_ASMLINKAGE
#endif

-#ifndef SYMBOL_NAME
-#ifdef CONFIG_SYMBOL_PREFIX
-#define SYMBOL_NAME(x) CONFIG_SYMBOL_PREFIX ## x
-#else
-#define SYMBOL_NAME(x) x
-#endif
-#endif
-#define __SYMBOL_NAME(x) __stringify(SYMBOL_NAME(x))
-
#ifndef cond_syscall
-#define cond_syscall(x) asm(".weak\t" __SYMBOL_NAME(x) \
- "\n\t.set\t" __SYMBOL_NAME(x) "," __SYMBOL_NAME(sys_ni_syscall));
+#define cond_syscall(x) asm(".weak\t" VMLINUX_SYMBOL_STR(x) "\n\t" \
+ ".set\t" VMLINUX_SYMBOL_STR(x) "," \
+ VMLINUX_SYMBOL_STR(sys_ni_syscall))
#endif

#ifndef SYSCALL_ALIAS
#define SYSCALL_ALIAS(alias, name) \
- asm ("\t.globl " __SYMBOL_NAME(alias) \
- "\n\t.set\t" __SYMBOL_NAME(alias) "," __SYMBOL_NAME(name))
+ asm ("\t.globl " VMLINUX_SYMBOL_STR(alias) \
+ "\n\t.set\t" VMLINUX_SYMBOL_STR(alias) "," VMLINUX_SYMBOL_STR(name))
#endif

#define __page_aligned_data __section(.data..page_aligned) __aligned(PAGE_SIZE)
--
1.8.1

--
Cheers,
Stephen Rothwell sfr@xxxxxxxxxxxxxxxx

Attachment: pgp00000.pgp
Description: PGP signature