lkml.org 
[lkml]   [2009]   [Aug]   [28]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
SubjectRe: modules: Fix build error in the !CONFIG_KALLSYMS case
From
Date
On Fri, 2009-08-28 at 10:44 +0200, Ingo Molnar wrote:
> * Linus Torvalds <torvalds@linux-foundation.org> wrote:
>
> > James Bottomley (1):
> > module: workaround duplicate section names
>
> -tip testing found that this patch breaks the build on x86 if
> CONFIG_KALLSYMS is disabled:
>
> kernel/module.c: In function ‘load_module’:
> kernel/module.c:2367: error: ‘struct module’ has no member named ‘sect_attrs’
> distcc[8269] ERROR: compile kernel/module.c on ph/32 failed
> make[1]: *** [kernel/module.o] Error 1
> make: *** [kernel] Error 2
> make: *** Waiting for unfinished jobs....
>
> Commit 1b364bf misses the fact that section attributes are only
> built and dealt with if kallsyms is enabled. The patch below fixes
> this.

Thanks for finding the bug.

> ( note, technically speaking this should depend on CONFIG_SYSFS as
> well but this patch is correct too and keeps the #ifdef less
> intrusive - in the KALLSYMS && !SYSFS case the code is a NOP. )

Agree with this, but there is a way of fixing it, see below.

> Signed-off-by: Ingo Molnar <mingo@elte.hu>
> ---
> kernel/module.c | 2 ++
> 1 files changed, 2 insertions(+), 0 deletions(-)
>
> diff --git a/kernel/module.c b/kernel/module.c
> index eccb561..b4016d1 100644
> --- a/kernel/module.c
> +++ b/kernel/module.c
> @@ -2355,8 +2355,10 @@ static noinline struct module *load_module(void __user *umod,
> if (err < 0)
> goto unlink;
> add_sect_attrs(mod, hdr->e_shnum, secstrings, sechdrs);
> +#ifdef CONFIG_KALLSYMS
> if (mod->sect_attrs)
> add_notes_attrs(mod, hdr->e_shnum, secstrings, sechdrs);
> +#endif

Rather than adding to the #ifdef litter in the file, isn't it better to
move the test to a section of it that's already ifdef'd?

This also fixes the problem of depending on CONFIG_SYSFS you mention.

James

---

diff --git a/kernel/module.c b/kernel/module.c
index eccb561..2d53718 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -1274,6 +1274,10 @@ static void add_notes_attrs(struct module *mod, unsigned int nsect,
struct module_notes_attrs *notes_attrs;
struct bin_attribute *nattr;

+ /* failed to create section attributes, so can't create notes */
+ if (!mod->sect_attrs)
+ return;
+
/* Count notes sections and allocate structures. */
notes = 0;
for (i = 0; i < nsect; i++)
@@ -2355,8 +2359,7 @@ static noinline struct module *load_module(void __user *umod,
if (err < 0)
goto unlink;
add_sect_attrs(mod, hdr->e_shnum, secstrings, sechdrs);
- if (mod->sect_attrs)
- add_notes_attrs(mod, hdr->e_shnum, secstrings, sechdrs);
+ add_notes_attrs(mod, hdr->e_shnum, secstrings, sechdrs);

/* Get rid of temporary copy */
vfree(hdr);

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2009-08-28 14:11    [W:1.603 / U:0.024 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site