Re: [PATCH] fix build error when CONFIG_SWAP is not set

On Mon, Jan 24, 2011 at 22:07, Sam Ravnborg [off-list ref] wrote:

On Mon, Jan 24, 2011 at 12:44:12PM -0800, Andrew Morton wrote:

quoted

On Mon, 24 Jan 2011 22:30:46 +0300
Sergei Shtylyov [off-list ref] wrote:

quoted

Yoichi Yuasa wrote:

quoted

In file included from
linux-2.6/arch/mips/include/asm/tlb.h:21,
                 from mm/pgtable-generic.c:9:
include/asm-generic/tlb.h: In function 'tlb_flush_mmu':
include/asm-generic/tlb.h:76: error: implicit declaration of function
'release_pages'
include/asm-generic/tlb.h: In function 'tlb_remove_page':
include/asm-generic/tlb.h:105: error: implicit declaration of function
'page_cache_release'
make[1]: *** [mm/pgtable-generic.o] Error 1

Signed-off-by: Yoichi Yuasa <redacted>

[...]

quoted

diff --git a/include/linux/swap.h b/include/linux/swap.h
index 4d55932..92c1be6 100644
--- a/include/linux/swap.h
+++ b/include/linux/swap.h

@@ -8,6 +8,7 @@

 #include <linux/memcontrol.h>
 #include <linux/sched.h>
 #include <linux/node.h>
+#include <linux/pagemap.h>

    Hm, if the errors are in <asm-generic/tlb.h>, why add #include in
<linux/swap.h>?

The build error is caused by macros which are defined in swap.h.

I worry about the effects of the patch - I don't know which of swap.h
and pagemap.h is the "innermost" header file.  There's potential for
new build errors due to strange inclusion graphs.

err, there's also this, in swap.h:

/* only sparc can not include linux/pagemap.h in this file
 * so leave page_cache_release and release_pages undeclared... */

Yeah, I noticed this too a while ago, when trying to get m68k
allnoconfig "working".
Was wondering whether this was still true...

I just checked.
sparc32 with a defconfig barfed out like this:
 CC      arch/sparc/kernel/traps_32.o
In file included from /home/sam/kernel/linux-2.6.git/include/linux/pagemap.h:7:0,
                from /home/sam/kernel/linux-2.6.git/include/linux/swap.h:11,
                from /home/sam/kernel/linux-2.6.git/arch/sparc/include/asm/pgtable_32.h:15,
                from /home/sam/kernel/linux-2.6.git/arch/sparc/include/asm/pgtable.h:6,
                from /home/sam/kernel/linux-2.6.git/arch/sparc/kernel/traps_32.c:23:
/home/sam/kernel/linux-2.6.git/include/linux/mm.h: In function 'is_vmalloc_addr':
/home/sam/kernel/linux-2.6.git/include/linux/mm.h:301:17: error: 'VMALLOC_START' undeclared (first use in this function)
/home/sam/kernel/linux-2.6.git/include/linux/mm.h:301:17: note: each undeclared identifier is reported only once for each function it appears in
/home/sam/kernel/linux-2.6.git/include/linux/mm.h:301:41: error: 'VMALLOC_END' undeclared (first use in this function)
/home/sam/kernel/linux-2.6.git/include/linux/mm.h: In function 'maybe_mkwrite':
/home/sam/kernel/linux-2.6.git/include/linux/mm.h:483:3: error: implicit declaration of function 'pte_mkwrite'

When I removed the include it could build again.

... and so it is. Good to know, thanks for checking!

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds

--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org.  For more info on Linux MM,
see: http://www.linux-mm.org/ .
Fight unfair telecom policy in Canada: sign http://dissolvethecrtc.ca/
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>