[PATCH] 2.6.14-rc5 fails to build with out CONFIG_FUTEX

[PATCH] 2.6.14-rc5 fails to build with out CONFIG_FUTEX

[George Anzinger]

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Both kernel/exit.c and fs/dcache.c refer to functions in kernel/futex.c which is not built unless 
CONFIG_FUTEX is true.  This causes a build failure at link time:
   LD      vmlinux
kernel/built-in.o(.text+0xab58): In function `do_exit':
/usr/src/linux-2.6.14-rc/kernel/exit.c:851: undefined reference to `exit_futex'
fs/built-in.o(.text+0x1b2bf): In function `dput':
/usr/src/linux-2.6.14-rc/fs/dcache.c:165: undefined reference to `futex_free_robust_list'

Attached patch "defines" away the problem.
-- 
George Anzinger   george@mvista.com
HRT (High-res-timers):  http://sourceforge.net/projects/high-res-timers/

[-- Attachment #2: futux-fix.patch --]
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Source: MontaVista Software, Inc.

Type: Defect Fix 
Description:
CONFIG_FUTEX is an option but kernel/exit.c and fs/dcache.c refer to functions in kernel/futux.c unconditionally.  This patch ties those request off and allows a build with CONFIG_FUTEX  "not set".

Signed-off-by: George Anzinger <george@mvista.com>

 include/linux/futex.h |    6 +++++-
 1 files changed, 5 insertions(+), 1 deletion(-)

Index: linux-2.6.14-rc/include/linux/futex.h
===================================================================
--- linux-2.6.14-rc.orig/include/linux/futex.h
+++ linux-2.6.14-rc/include/linux/futex.h
@@ -35,9 +35,13 @@
 long do_futex(unsigned long uaddr, int op, int val,
 		unsigned long timeout, unsigned long uaddr2, int val2,
 		int val3);
-
+#ifdef CONFIG_FUTEX
 extern void futex_free_robust_list(struct inode *inode);
 extern void exit_futex(struct task_struct *tsk);
+#else
+#define futex_free_robust_list(a)
+#define exit_futex(b)
+#endif
 static inline void futex_init_inode(struct inode *inode)
 {
 	INIT_LIST_HEAD(&inode->i_data.robust_list);

Re: [PATCH] 2.6.14-rc5 fails to build with out CONFIG_FUTEX

[Andrew Morton]

George Anzinger <george@mvista.com> wrote:
>
> Both kernel/exit.c and fs/dcache.c refer to functions in kernel/futex.c which is not built unless 
> CONFIG_FUTEX is true.  This causes a build failure at link time:
>    LD      vmlinux
> kernel/built-in.o(.text+0xab58): In function `do_exit':
> /usr/src/linux-2.6.14-rc/kernel/exit.c:851: undefined reference to `exit_futex'
> fs/built-in.o(.text+0x1b2bf): In function `dput':
> /usr/src/linux-2.6.14-rc/fs/dcache.c:165: undefined reference to `futex_free_robust_list'

This problem is specific to the robust-futexes patch.

Re: [PATCH] 2.6.14-rc5 fails to build with out CONFIG_FUTEX

[George Anzinger]

Andrew Morton wrote:
> George Anzinger <george@mvista.com> wrote:
> 
>>Both kernel/exit.c and fs/dcache.c refer to functions in kernel/futex.c which is not built unless 
>>CONFIG_FUTEX is true.  This causes a build failure at link time:
>>   LD      vmlinux
>>kernel/built-in.o(.text+0xab58): In function `do_exit':
>>/usr/src/linux-2.6.14-rc/kernel/exit.c:851: undefined reference to `exit_futex'
>>fs/built-in.o(.text+0x1b2bf): In function `dput':
>>/usr/src/linux-2.6.14-rc/fs/dcache.c:165: undefined reference to `futex_free_robust_list'
> 
> 
> This problem is specific to the robust-futexes patch.

And that appears to be in rc5, right?

-- 
George Anzinger   george@mvista.com
HRT (High-res-timers):  http://sourceforge.net/projects/high-res-timers/

Re: [PATCH] 2.6.14-rc5 fails to build with out CONFIG_FUTEX

[Andrew Morton]

George Anzinger <george@mvista.com> wrote:
>
> Andrew Morton wrote:
> > George Anzinger <george@mvista.com> wrote:
> > 
> >>Both kernel/exit.c and fs/dcache.c refer to functions in kernel/futex.c which is not built unless 
> >>CONFIG_FUTEX is true.  This causes a build failure at link time:
> >>   LD      vmlinux
> >>kernel/built-in.o(.text+0xab58): In function `do_exit':
> >>/usr/src/linux-2.6.14-rc/kernel/exit.c:851: undefined reference to `exit_futex'
> >>fs/built-in.o(.text+0x1b2bf): In function `dput':
> >>/usr/src/linux-2.6.14-rc/fs/dcache.c:165: undefined reference to `futex_free_robust_list'
> > 
> > 
> > This problem is specific to the robust-futexes patch.
> 
> And that appears to be in rc5, right?
> 

Nope.  Your patch is not applicable to mainline kernels.

Re: [PATCH] 2.6.14-rc5 fails to build with out CONFIG_FUTEX

[George Anzinger]

Andrew Morton wrote:
> George Anzinger <george@mvista.com> wrote:
> 
>>Andrew Morton wrote:
>>
>>>George Anzinger <george@mvista.com> wrote:
>>>
>>>
>>>>Both kernel/exit.c and fs/dcache.c refer to functions in kernel/futex.c which is not built unless 
>>>>CONFIG_FUTEX is true.  This causes a build failure at link time:
>>>>  LD      vmlinux
>>>>kernel/built-in.o(.text+0xab58): In function `do_exit':
>>>>/usr/src/linux-2.6.14-rc/kernel/exit.c:851: undefined reference to `exit_futex'
>>>>fs/built-in.o(.text+0x1b2bf): In function `dput':
>>>>/usr/src/linux-2.6.14-rc/fs/dcache.c:165: undefined reference to `futex_free_robust_list'
>>>
>>>
>>>This problem is specific to the robust-futexes patch.
>>
>>And that appears to be in rc5, right?
>>
Ok, got it, excuse the noise.

-- 
George Anzinger   george@mvista.com
HRT (High-res-timers):  http://sourceforge.net/projects/high-res-timers/

Re: [PATCH] 2.6.14-rc5 fails to build with out CONFIG_FUTEX

[Ingo Molnar]

* George Anzinger <george@mvista.com> wrote:

> Both kernel/exit.c and fs/dcache.c refer to functions in 
> kernel/futex.c which is not built unless CONFIG_FUTEX is true.  This 
> causes a build failure at link time:

uhm, -rt5 you wanted to write, and a different Cc: list, right? :-)

otherwise, thanks and applied.

	Ingo