[Patch] uml: drop const qualifier for kernel_execve()

[Patch] uml: drop const qualifier for kernel_execve()

[Américo Wang]

UML implementation of kernel_execve() should not have const qualifier,
because it will finally call do_execve() which doesn't have.

This also shuts up a gcc warning on this.

Signed-off-by: WANG Cong <wangcong@zeuux.org>
Cc: Jeff Dike <jdike@addtoit.com>

---
diff --git a/arch/um/kernel/syscall.c b/arch/um/kernel/syscall.c
index c4df705..4fa62ee 100644
--- a/arch/um/kernel/syscall.c
+++ b/arch/um/kernel/syscall.c
@@ -120,7 +120,7 @@ long sys_olduname(struct oldold_utsname __user * name)
 	return error;
 }

-int kernel_execve(const char *filename, char *const argv[], char *const envp[])
+int kernel_execve(char *filename, char * argv[], char * envp[])
 {
 	mm_segment_t fs;
 	int ret;

Re: [Patch] uml: drop const qualifier for kernel_execve()

[Johannes Weiner]

On Tue, Dec 02, 2008 at 10:51:09PM +0000, Américo Wang wrote:
> UML implementation of kernel_execve() should not have const qualifier,
> because it will finally call do_execve() which doesn't have.

And you made sure that do_execve() is correctly annotated?

	Hannes

Re: [Patch] uml: drop const qualifier for kernel_execve()

[Américo Wang]

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On Wed, Dec 3, 2008 at 1:20 AM, Johannes Weiner <hannes@cmpxchg.org> wrote:> On Tue, Dec 02, 2008 at 10:51:09PM +0000, Américo Wang wrote:>> UML implementation of kernel_execve() should not have const qualifier,>> because it will finally call do_execve() which doesn't have.>> And you made sure that do_execve() is correctly annotated?>
Yes, I checked that.
Thanks.ÿôèº{.nÇ+‰·Ÿ®‰­†+%ŠËÿ±éݶ\x17¥Šwÿº{.nÇ+‰·¥Š{±þG«éÿŠ{ayº\x1dʇڙë,j\a­¢f£¢·hšïêÿ‘êçz_è®\x03(­éšŽŠÝ¢j"ú\x1a¶^[m§ÿÿ¾\a«þG«éÿ¢¸?™¨è­Ú&£ø§~á¶iO•æ¬z·švØ^\x14\x04\x1a¶^[m§ÿÿÃ\fÿ¶ìÿ¢¸?–I¥

Re: [Patch] uml: drop const qualifier for kernel_execve()

[Johannes Weiner]

On Wed, Dec 03, 2008 at 12:32:02PM +0000, Américo Wang wrote:
> On Wed, Dec 3, 2008 at 1:20 AM, Johannes Weiner <hannes@cmpxchg.org> wrote:
> > On Tue, Dec 02, 2008 at 10:51:09PM +0000, Américo Wang wrote:
> >> UML implementation of kernel_execve() should not have const qualifier,
> >> because it will finally call do_execve() which doesn't have.
> >
> > And you made sure that do_execve() is correctly annotated?
> >
> 
> Yes, I checked that.

Good.  Then please fix up do_execve() or let the warning stand out as
a reminder.

	Hannes

Re: [Patch] uml: drop const qualifier for kernel_execve()

[Américo Wang]

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On Wed, Dec 3, 2008 at 1:40 PM, Johannes Weiner <hannes@cmpxchg.org> wrote:> On Wed, Dec 03, 2008 at 12:32:02PM +0000, Américo Wang wrote:>> On Wed, Dec 3, 2008 at 1:20 AM, Johannes Weiner <hannes@cmpxchg.org> wrote:>> > On Tue, Dec 02, 2008 at 10:51:09PM +0000, Américo Wang wrote:>> >> UML implementation of kernel_execve() should not have const qualifier,>> >> because it will finally call do_execve() which doesn't have.>> >>> > And you made sure that do_execve() is correctly annotated?>> >>>>> Yes, I checked that.>> Good.  Then please fix up do_execve() or let the warning stand out as> a reminder.
??Confused...
do_execve() is OK, we don't need to fix it.
Thanks.ÿôèº{.nÇ+‰·Ÿ®‰­†+%ŠËÿ±éݶ\x17¥Šwÿº{.nÇ+‰·¥Š{±þG«éÿŠ{ayº\x1dʇڙë,j\a­¢f£¢·hšïêÿ‘êçz_è®\x03(­éšŽŠÝ¢j"ú\x1a¶^[m§ÿÿ¾\a«þG«éÿ¢¸?™¨è­Ú&£ø§~á¶iO•æ¬z·švØ^\x14\x04\x1a¶^[m§ÿÿÃ\fÿ¶ìÿ¢¸?–I¥

Re: [Patch] uml: drop const qualifier for kernel_execve()

[Johannes Weiner]

On Sat, Dec 06, 2008 at 01:02:16AM +0000, Américo Wang wrote:
> On Wed, Dec 3, 2008 at 1:40 PM, Johannes Weiner <hannes@cmpxchg.org> wrote:
> > On Wed, Dec 03, 2008 at 12:32:02PM +0000, Américo Wang wrote:
> >> On Wed, Dec 3, 2008 at 1:20 AM, Johannes Weiner <hannes@cmpxchg.org> wrote:
> >> > On Tue, Dec 02, 2008 at 10:51:09PM +0000, Américo Wang wrote:
> >> >> UML implementation of kernel_execve() should not have const qualifier,
> >> >> because it will finally call do_execve() which doesn't have.
> >> >
> >> > And you made sure that do_execve() is correctly annotated?
> >> >
> >>
> >> Yes, I checked that.
> >
> > Good.  Then please fix up do_execve() or let the warning stand out as
> > a reminder.
> 
> ??
> Confused...
> 
> do_execve() is OK, we don't need to fix it.

I don't see where it writes through @filename.  So it seems the right
fix would be to make do_execve()s parameter const (and as it seems, a
lot more adjustments down this call graph) and not remove a correct
const from a callsite.

	Hannes

Re: [Patch] uml: drop const qualifier for kernel_execve()

[Américo Wang]

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On Sun, Dec 7, 2008 at 7:55 PM, Johannes Weiner <hannes@cmpxchg.org> wrote:> On Sat, Dec 06, 2008 at 01:02:16AM +0000, Américo Wang wrote:>> On Wed, Dec 3, 2008 at 1:40 PM, Johannes Weiner <hannes@cmpxchg.org> wrote:>> > On Wed, Dec 03, 2008 at 12:32:02PM +0000, Américo Wang wrote:>> >> On Wed, Dec 3, 2008 at 1:20 AM, Johannes Weiner <hannes@cmpxchg.org> wrote:>> >> > On Tue, Dec 02, 2008 at 10:51:09PM +0000, Américo Wang wrote:>> >> >> UML implementation of kernel_execve() should not have const qualifier,>> >> >> because it will finally call do_execve() which doesn't have.>> >> >>> >> > And you made sure that do_execve() is correctly annotated?>> >> >>> >>>> >> Yes, I checked that.>> >>> > Good.  Then please fix up do_execve() or let the warning stand out as>> > a reminder.>>>> ??>> Confused...>>>> do_execve() is OK, we don't need to fix it.>> I don't see where it writes through @filename.  So it seems the right> fix would be to make do_execve()s parameter const (and as it seems, a> lot more adjustments down this call graph) and not remove a correct> const from a callsite.
Hello, Johannes.
I apologize for my late reply.
Well, not only @filename, but also the next two parameters, but if you alsomake them const in do_execve(), you will get more warnings. :)So I think my patch is correct.
Thanks for your review.ÿôèº{.nÇ+‰·Ÿ®‰­†+%ŠËÿ±éݶ\x17¥Šwÿº{.nÇ+‰·¥Š{±þG«éÿŠ{ayº\x1dʇڙë,j\a­¢f£¢·hšïêÿ‘êçz_è®\x03(­éšŽŠÝ¢j"ú\x1a¶^[m§ÿÿ¾\a«þG«éÿ¢¸?™¨è­Ú&£ø§~á¶iO•æ¬z·švØ^\x14\x04\x1a¶^[m§ÿÿÃ\fÿ¶ìÿ¢¸?–I¥