2019-09-07 08:07:23

by Arnd Bergmann

[permalink] [raw]
Subject: [PATCH] ARM: don't export unused return_address()

Without the frame pointer enabled, return_address() is an inline
function and does not need to be exported, as shown by this warning:

WARNING: "return_address" [vmlinux] is a static EXPORT_SYMBOL_GPL

Move the EXPORT_SYMBOL_GPL() into the #ifdef as well.

Signed-off-by: Arnd Bergmann <[email protected]>
---
arch/arm/kernel/return_address.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/arch/arm/kernel/return_address.c b/arch/arm/kernel/return_address.c
index b0d2f1fe891d..fb0fc1910102 100644
--- a/arch/arm/kernel/return_address.c
+++ b/arch/arm/kernel/return_address.c
@@ -53,6 +53,7 @@ void *return_address(unsigned int level)
return NULL;
}

+EXPORT_SYMBOL_GPL(return_address);
+
#endif /* if defined(CONFIG_FRAME_POINTER) && !defined(CONFIG_ARM_UNWIND) */

-EXPORT_SYMBOL_GPL(return_address);
--
2.20.0


2019-09-26 00:43:03

by Masahiro Yamada

[permalink] [raw]
Subject: Re: [PATCH] ARM: don't export unused return_address()

On Sat, Sep 7, 2019 at 12:47 AM Arnd Bergmann <[email protected]> wrote:
>
> Without the frame pointer enabled, return_address() is an inline
> function and does not need to be exported, as shown by this warning:
>
> WARNING: "return_address" [vmlinux] is a static EXPORT_SYMBOL_GPL
>
> Move the EXPORT_SYMBOL_GPL() into the #ifdef as well.
>
> Signed-off-by: Arnd Bergmann <[email protected]>


Reviewed-by: Masahiro Yamada <[email protected]>



--
Best Regards
Masahiro Yamada

2019-10-01 14:34:55

by Geert Uytterhoeven

[permalink] [raw]
Subject: Re: [PATCH] ARM: don't export unused return_address()

Hi Arnd,

On Fri, Sep 6, 2019 at 5:47 PM Arnd Bergmann <[email protected]> wrote:
> Without the frame pointer enabled, return_address() is an inline
> function and does not need to be exported, as shown by this warning:
>
> WARNING: "return_address" [vmlinux] is a static EXPORT_SYMBOL_GPL
>
> Move the EXPORT_SYMBOL_GPL() into the #ifdef as well.
>
> Signed-off-by: Arnd Bergmann <[email protected]>

Thanks for your patch!

Tested-by: Geert Uytterhoeven <[email protected]>

> --- a/arch/arm/kernel/return_address.c
> +++ b/arch/arm/kernel/return_address.c
> @@ -53,6 +53,7 @@ void *return_address(unsigned int level)
> return NULL;
> }
>

Checkpatch doesn't like the empty line above:

WARNING: EXPORT_SYMBOL(foo); should immediately follow its function/variable

> +EXPORT_SYMBOL_GPL(return_address);
> +
> #endif /* if defined(CONFIG_FRAME_POINTER) && !defined(CONFIG_ARM_UNWIND) */
>
> -EXPORT_SYMBOL_GPL(return_address);

Gr{oetje,eeting}s,

Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- [email protected]

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

2019-11-13 11:44:55

by Masahiro Yamada

[permalink] [raw]
Subject: Re: [PATCH] ARM: don't export unused return_address()

On Tue, Oct 1, 2019 at 11:31 PM Geert Uytterhoeven <[email protected]> wrote:
>
> Hi Arnd,
>
> On Fri, Sep 6, 2019 at 5:47 PM Arnd Bergmann <[email protected]> wrote:
> > Without the frame pointer enabled, return_address() is an inline
> > function and does not need to be exported, as shown by this warning:
> >
> > WARNING: "return_address" [vmlinux] is a static EXPORT_SYMBOL_GPL
> >
> > Move the EXPORT_SYMBOL_GPL() into the #ifdef as well.
> >
> > Signed-off-by: Arnd Bergmann <[email protected]>
>
> Thanks for your patch!
>
> Tested-by: Geert Uytterhoeven <[email protected]>
>
> > --- a/arch/arm/kernel/return_address.c
> > +++ b/arch/arm/kernel/return_address.c
> > @@ -53,6 +53,7 @@ void *return_address(unsigned int level)
> > return NULL;
> > }
> >
>
> Checkpatch doesn't like the empty line above:
>
> WARNING: EXPORT_SYMBOL(foo); should immediately follow its function/variable
>
> > +EXPORT_SYMBOL_GPL(return_address);
> > +
> > #endif /* if defined(CONFIG_FRAME_POINTER) && !defined(CONFIG_ARM_UNWIND) */
> >
> > -EXPORT_SYMBOL_GPL(return_address);
>
> Gr{oetje,eeting}s,
>
> Geert
>
> --
> Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- [email protected]
>
> 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



What has happened to this patch?

I still see this warning.



--
Best Regards
Masahiro Yamada

2019-11-13 11:47:12

by Russell King (Oracle)

[permalink] [raw]
Subject: Re: [PATCH] ARM: don't export unused return_address()

On Wed, Nov 13, 2019 at 08:40:39PM +0900, Masahiro Yamada wrote:
> On Tue, Oct 1, 2019 at 11:31 PM Geert Uytterhoeven <[email protected]> wrote:
> >
> > Hi Arnd,
> >
> > On Fri, Sep 6, 2019 at 5:47 PM Arnd Bergmann <[email protected]> wrote:
> > > Without the frame pointer enabled, return_address() is an inline
> > > function and does not need to be exported, as shown by this warning:
> > >
> > > WARNING: "return_address" [vmlinux] is a static EXPORT_SYMBOL_GPL
> > >
> > > Move the EXPORT_SYMBOL_GPL() into the #ifdef as well.
> > >
> > > Signed-off-by: Arnd Bergmann <[email protected]>
> >
> > Thanks for your patch!
> >
> > Tested-by: Geert Uytterhoeven <[email protected]>
> >
> > > --- a/arch/arm/kernel/return_address.c
> > > +++ b/arch/arm/kernel/return_address.c
> > > @@ -53,6 +53,7 @@ void *return_address(unsigned int level)
> > > return NULL;
> > > }
> > >
> >
> > Checkpatch doesn't like the empty line above:
> >
> > WARNING: EXPORT_SYMBOL(foo); should immediately follow its function/variable
> >
> > > +EXPORT_SYMBOL_GPL(return_address);
> > > +
> > > #endif /* if defined(CONFIG_FRAME_POINTER) && !defined(CONFIG_ARM_UNWIND) */
> > >
> > > -EXPORT_SYMBOL_GPL(return_address);
> >
> > Gr{oetje,eeting}s,
> >
> > Geert
> >
> > --
> > Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- [email protected]
> >
> > 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
>
>
>
> What has happened to this patch?
>
> I still see this warning.

Simple - it got merged, it caused build regressions, it got dropped.
A new version is pending me doing another round of patch merging.

--
RMK's Patch system: https://www.armlinux.org.uk/developer/patches/
FTTC broadband for 0.8mile line in suburbia: sync at 12.1Mbps down 622kbps up
According to speedtest.net: 11.9Mbps down 500kbps up

2019-11-13 13:19:21

by Geert Uytterhoeven

[permalink] [raw]
Subject: Re: [PATCH] ARM: don't export unused return_address()

Hi Russell,

On Wed, Nov 13, 2019 at 12:45 PM Russell King - ARM Linux admin
<[email protected]> wrote:
> On Wed, Nov 13, 2019 at 08:40:39PM +0900, Masahiro Yamada wrote:
> > On Tue, Oct 1, 2019 at 11:31 PM Geert Uytterhoeven <[email protected]> wrote:
> > > On Fri, Sep 6, 2019 at 5:47 PM Arnd Bergmann <[email protected]> wrote:
> > > > Without the frame pointer enabled, return_address() is an inline
> > > > function and does not need to be exported, as shown by this warning:
> > > >
> > > > WARNING: "return_address" [vmlinux] is a static EXPORT_SYMBOL_GPL
> > > >
> > > > Move the EXPORT_SYMBOL_GPL() into the #ifdef as well.
> > > >
> > > > Signed-off-by: Arnd Bergmann <[email protected]>
> > >
> > > Thanks for your patch!
> > >
> > > Tested-by: Geert Uytterhoeven <[email protected]>
> > >
> > > > --- a/arch/arm/kernel/return_address.c
> > > > +++ b/arch/arm/kernel/return_address.c
> > > > @@ -53,6 +53,7 @@ void *return_address(unsigned int level)
> > > > return NULL;
> > > > }
> > > >
> > >
> > > Checkpatch doesn't like the empty line above:
> > >
> > > WARNING: EXPORT_SYMBOL(foo); should immediately follow its function/variable
> > >
> > > > +EXPORT_SYMBOL_GPL(return_address);
> > > > +
> > > > #endif /* if defined(CONFIG_FRAME_POINTER) && !defined(CONFIG_ARM_UNWIND) */
> > > >
> > > > -EXPORT_SYMBOL_GPL(return_address);

> > What has happened to this patch?
> >
> > I still see this warning.
>
> Simple - it got merged, it caused build regressions, it got dropped.
> A new version is pending me doing another round of patch merging.

I believe that was not Arnd's patch, but Ben Dooks' alternative solution[*]?

[*] Commit 0b0617e5a610fe12 ("ARM: 8918/1: only build return_address() if
needed"), which I discovered in next-20191031 when checking if Arnd's
patch was applied....


Gr{oetje,eeting}s,

Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- [email protected]

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

2019-11-13 17:21:34

by Russell King (Oracle)

[permalink] [raw]
Subject: Re: [PATCH] ARM: don't export unused return_address()

On Wed, Nov 13, 2019 at 02:15:00PM +0100, Geert Uytterhoeven wrote:
> Hi Russell,
>
> On Wed, Nov 13, 2019 at 12:45 PM Russell King - ARM Linux admin
> <[email protected]> wrote:
> > On Wed, Nov 13, 2019 at 08:40:39PM +0900, Masahiro Yamada wrote:
> > > On Tue, Oct 1, 2019 at 11:31 PM Geert Uytterhoeven <[email protected]> wrote:
> > > > On Fri, Sep 6, 2019 at 5:47 PM Arnd Bergmann <[email protected]> wrote:
> > > > > Without the frame pointer enabled, return_address() is an inline
> > > > > function and does not need to be exported, as shown by this warning:
> > > > >
> > > > > WARNING: "return_address" [vmlinux] is a static EXPORT_SYMBOL_GPL
> > > > >
> > > > > Move the EXPORT_SYMBOL_GPL() into the #ifdef as well.
> > > > >
> > > > > Signed-off-by: Arnd Bergmann <[email protected]>
> > > >
> > > > Thanks for your patch!
> > > >
> > > > Tested-by: Geert Uytterhoeven <[email protected]>
> > > >
> > > > > --- a/arch/arm/kernel/return_address.c
> > > > > +++ b/arch/arm/kernel/return_address.c
> > > > > @@ -53,6 +53,7 @@ void *return_address(unsigned int level)
> > > > > return NULL;
> > > > > }
> > > > >
> > > >
> > > > Checkpatch doesn't like the empty line above:
> > > >
> > > > WARNING: EXPORT_SYMBOL(foo); should immediately follow its function/variable
> > > >
> > > > > +EXPORT_SYMBOL_GPL(return_address);
> > > > > +
> > > > > #endif /* if defined(CONFIG_FRAME_POINTER) && !defined(CONFIG_ARM_UNWIND) */
> > > > >
> > > > > -EXPORT_SYMBOL_GPL(return_address);
>
> > > What has happened to this patch?
> > >
> > > I still see this warning.
> >
> > Simple - it got merged, it caused build regressions, it got dropped.
> > A new version is pending me doing another round of patch merging.
>
> I believe that was not Arnd's patch, but Ben Dooks' alternative solution[*]?

I don't keep track of who did what, sorry.

>
> [*] Commit 0b0617e5a610fe12 ("ARM: 8918/1: only build return_address() if
> needed"), which I discovered in next-20191031 when checking if Arnd's
> patch was applied....
--
RMK's Patch system: https://www.armlinux.org.uk/developer/patches/
FTTC broadband for 0.8mile line in suburbia: sync at 12.1Mbps down 622kbps up
According to speedtest.net: 11.9Mbps down 500kbps up

2019-11-20 09:08:09

by Masahiro Yamada

[permalink] [raw]
Subject: Re: [PATCH] ARM: don't export unused return_address()

Hi Arnd,



On Thu, Nov 14, 2019 at 2:01 AM Russell King - ARM Linux admin
<[email protected]> wrote:
>
> On Wed, Nov 13, 2019 at 02:15:00PM +0100, Geert Uytterhoeven wrote:
> > Hi Russell,
> >
> > On Wed, Nov 13, 2019 at 12:45 PM Russell King - ARM Linux admin
> > <[email protected]> wrote:
> > > On Wed, Nov 13, 2019 at 08:40:39PM +0900, Masahiro Yamada wrote:
> > > > On Tue, Oct 1, 2019 at 11:31 PM Geert Uytterhoeven <[email protected]> wrote:
> > > > > On Fri, Sep 6, 2019 at 5:47 PM Arnd Bergmann <[email protected]> wrote:
> > > > > > Without the frame pointer enabled, return_address() is an inline
> > > > > > function and does not need to be exported, as shown by this warning:
> > > > > >
> > > > > > WARNING: "return_address" [vmlinux] is a static EXPORT_SYMBOL_GPL
> > > > > >
> > > > > > Move the EXPORT_SYMBOL_GPL() into the #ifdef as well.
> > > > > >
> > > > > > Signed-off-by: Arnd Bergmann <[email protected]>
> > > > >
> > > > > Thanks for your patch!
> > > > >
> > > > > Tested-by: Geert Uytterhoeven <[email protected]>
> > > > >
> > > > > > --- a/arch/arm/kernel/return_address.c
> > > > > > +++ b/arch/arm/kernel/return_address.c
> > > > > > @@ -53,6 +53,7 @@ void *return_address(unsigned int level)
> > > > > > return NULL;
> > > > > > }
> > > > > >
> > > > >
> > > > > Checkpatch doesn't like the empty line above:
> > > > >
> > > > > WARNING: EXPORT_SYMBOL(foo); should immediately follow its function/variable
> > > > >
> > > > > > +EXPORT_SYMBOL_GPL(return_address);
> > > > > > +
> > > > > > #endif /* if defined(CONFIG_FRAME_POINTER) && !defined(CONFIG_ARM_UNWIND) */
> > > > > >
> > > > > > -EXPORT_SYMBOL_GPL(return_address);
> >
> > > > What has happened to this patch?
> > > >
> > > > I still see this warning.
> > >
> > > Simple - it got merged, it caused build regressions, it got dropped.
> > > A new version is pending me doing another round of patch merging.
> >
> > I believe that was not Arnd's patch, but Ben Dooks' alternative solution[*]?
>
> I don't keep track of who did what, sorry.


Arnd,

I believe this patch is the correct fix.
Could you please put it into Russell's patch tracker?
([email protected])





> >
> > [*] Commit 0b0617e5a610fe12 ("ARM: 8918/1: only build return_address() if
> > needed"), which I discovered in next-20191031 when checking if Arnd's
> > patch was applied....
> --
> RMK's Patch system: https://www.armlinux.org.uk/developer/patches/
> FTTC broadband for 0.8mile line in suburbia: sync at 12.1Mbps down 622kbps up
> According to speedtest.net: 11.9Mbps down 500kbps up


--
Best Regards
Masahiro Yamada

2019-11-20 09:12:01

by Russell King (Oracle)

[permalink] [raw]
Subject: Re: [PATCH] ARM: don't export unused return_address()

On Wed, Nov 20, 2019 at 06:02:13PM +0900, Masahiro Yamada wrote:
> Hi Arnd,
>
>
>
> On Thu, Nov 14, 2019 at 2:01 AM Russell King - ARM Linux admin
> <[email protected]> wrote:
> >
> > On Wed, Nov 13, 2019 at 02:15:00PM +0100, Geert Uytterhoeven wrote:
> > > Hi Russell,
> > >
> > > On Wed, Nov 13, 2019 at 12:45 PM Russell King - ARM Linux admin
> > > <[email protected]> wrote:
> > > > On Wed, Nov 13, 2019 at 08:40:39PM +0900, Masahiro Yamada wrote:
> > > > > On Tue, Oct 1, 2019 at 11:31 PM Geert Uytterhoeven <[email protected]> wrote:
> > > > > > On Fri, Sep 6, 2019 at 5:47 PM Arnd Bergmann <[email protected]> wrote:
> > > > > > > Without the frame pointer enabled, return_address() is an inline
> > > > > > > function and does not need to be exported, as shown by this warning:
> > > > > > >
> > > > > > > WARNING: "return_address" [vmlinux] is a static EXPORT_SYMBOL_GPL
> > > > > > >
> > > > > > > Move the EXPORT_SYMBOL_GPL() into the #ifdef as well.
> > > > > > >
> > > > > > > Signed-off-by: Arnd Bergmann <[email protected]>
> > > > > >
> > > > > > Thanks for your patch!
> > > > > >
> > > > > > Tested-by: Geert Uytterhoeven <[email protected]>
> > > > > >
> > > > > > > --- a/arch/arm/kernel/return_address.c
> > > > > > > +++ b/arch/arm/kernel/return_address.c
> > > > > > > @@ -53,6 +53,7 @@ void *return_address(unsigned int level)
> > > > > > > return NULL;
> > > > > > > }
> > > > > > >
> > > > > >
> > > > > > Checkpatch doesn't like the empty line above:
> > > > > >
> > > > > > WARNING: EXPORT_SYMBOL(foo); should immediately follow its function/variable
> > > > > >
> > > > > > > +EXPORT_SYMBOL_GPL(return_address);
> > > > > > > +
> > > > > > > #endif /* if defined(CONFIG_FRAME_POINTER) && !defined(CONFIG_ARM_UNWIND) */
> > > > > > >
> > > > > > > -EXPORT_SYMBOL_GPL(return_address);
> > >
> > > > > What has happened to this patch?
> > > > >
> > > > > I still see this warning.
> > > >
> > > > Simple - it got merged, it caused build regressions, it got dropped.
> > > > A new version is pending me doing another round of patch merging.
> > >
> > > I believe that was not Arnd's patch, but Ben Dooks' alternative solution[*]?
> >
> > I don't keep track of who did what, sorry.
>
>
> Arnd,
>
> I believe this patch is the correct fix.
> Could you please put it into Russell's patch tracker?
> ([email protected])

Is there something wrong with:

fb033c95c94c ARM: 8918/2: only build return_address() if needed

I haven't seen any build issues with that.

--
RMK's Patch system: https://www.armlinux.org.uk/developer/patches/
FTTC broadband for 0.8mile line in suburbia: sync at 12.1Mbps down 622kbps up
According to speedtest.net: 11.9Mbps down 500kbps up

2019-11-20 10:29:01

by Russell King (Oracle)

[permalink] [raw]
Subject: Re: [PATCH] ARM: don't export unused return_address()

On Wed, Nov 20, 2019 at 06:42:52PM +0900, Masahiro Yamada wrote:
> Hi Russell,
>
>
> On Wed, Nov 20, 2019 at 6:07 PM Russell King - ARM Linux admin
> <[email protected]> wrote:
> >
> > On Wed, Nov 20, 2019 at 06:02:13PM +0900, Masahiro Yamada wrote:
> > > Hi Arnd,
> > >
> > >
> > >
> > > On Thu, Nov 14, 2019 at 2:01 AM Russell King - ARM Linux admin
> > > <[email protected]> wrote:
> > > >
> > > > On Wed, Nov 13, 2019 at 02:15:00PM +0100, Geert Uytterhoeven wrote:
> > > > > Hi Russell,
> > > > >
> > > > > On Wed, Nov 13, 2019 at 12:45 PM Russell King - ARM Linux admin
> > > > > <[email protected]> wrote:
> > > > > > On Wed, Nov 13, 2019 at 08:40:39PM +0900, Masahiro Yamada wrote:
> > > > > > > On Tue, Oct 1, 2019 at 11:31 PM Geert Uytterhoeven <[email protected]> wrote:
> > > > > > > > On Fri, Sep 6, 2019 at 5:47 PM Arnd Bergmann <[email protected]> wrote:
> > > > > > > > > Without the frame pointer enabled, return_address() is an inline
> > > > > > > > > function and does not need to be exported, as shown by this warning:
> > > > > > > > >
> > > > > > > > > WARNING: "return_address" [vmlinux] is a static EXPORT_SYMBOL_GPL
> > > > > > > > >
> > > > > > > > > Move the EXPORT_SYMBOL_GPL() into the #ifdef as well.
> > > > > > > > >
> > > > > > > > > Signed-off-by: Arnd Bergmann <[email protected]>
> > > > > > > >
> > > > > > > > Thanks for your patch!
> > > > > > > >
> > > > > > > > Tested-by: Geert Uytterhoeven <[email protected]>
> > > > > > > >
> > > > > > > > > --- a/arch/arm/kernel/return_address.c
> > > > > > > > > +++ b/arch/arm/kernel/return_address.c
> > > > > > > > > @@ -53,6 +53,7 @@ void *return_address(unsigned int level)
> > > > > > > > > return NULL;
> > > > > > > > > }
> > > > > > > > >
> > > > > > > >
> > > > > > > > Checkpatch doesn't like the empty line above:
> > > > > > > >
> > > > > > > > WARNING: EXPORT_SYMBOL(foo); should immediately follow its function/variable
> > > > > > > >
> > > > > > > > > +EXPORT_SYMBOL_GPL(return_address);
> > > > > > > > > +
> > > > > > > > > #endif /* if defined(CONFIG_FRAME_POINTER) && !defined(CONFIG_ARM_UNWIND) */
> > > > > > > > >
> > > > > > > > > -EXPORT_SYMBOL_GPL(return_address);
> > > > >
> > > > > > > What has happened to this patch?
> > > > > > >
> > > > > > > I still see this warning.
> > > > > >
> > > > > > Simple - it got merged, it caused build regressions, it got dropped.
> > > > > > A new version is pending me doing another round of patch merging.
> > > > >
> > > > > I believe that was not Arnd's patch, but Ben Dooks' alternative solution[*]?
> > > >
> > > > I don't keep track of who did what, sorry.
> > >
> > >
> > > Arnd,
> > >
> > > I believe this patch is the correct fix.
> > > Could you please put it into Russell's patch tracker?
> > > ([email protected])
> >
> > Is there something wrong with:
> >
> > fb033c95c94c ARM: 8918/2: only build return_address() if needed
> >
> > I haven't seen any build issues with that.
>
>
> Sorry, I had not checked Ben's patch because you said
> "Simple - it got merged, it caused build regressions, it got dropped."

That was 8918/1. Ben fixed his patch, and submitted an updated
version.

> Yup, I've checked it right now,
> and it looks good to me.
>
> But, I do not see that commit in the latest linux-next
> (next-20191120).
>
> Could you really apply it if you have not.

It was applied last Friday and was pushed out there and then.

$ git ls-remote zeniv | grep for-next
022eb8ae8b5ee8c5c813923c69b5ebb1e9612c4c refs/heads/for-next
$ git lg for-next
022eb8ae8b5e ARM: 8938/1: kernel: initialize broadcast hrtimer based
clock event device
...
fb033c95c94c ARM: 8918/2: only build return_address() if needed

I've no idea why linux-next doesn't have it.

--
RMK's Patch system: https://www.armlinux.org.uk/developer/patches/
FTTC broadband for 0.8mile line in suburbia: sync at 12.1Mbps down 622kbps up
According to speedtest.net: 11.9Mbps down 500kbps up

2019-11-20 11:44:05

by Masahiro Yamada

[permalink] [raw]
Subject: Re: [PATCH] ARM: don't export unused return_address()

On Wed, Nov 20, 2019 at 7:07 PM Russell King - ARM Linux admin
<[email protected]> wrote:
>
> On Wed, Nov 20, 2019 at 09:51:11AM +0000, Russell King - ARM Linux admin wrote:
> > On Wed, Nov 20, 2019 at 06:42:52PM +0900, Masahiro Yamada wrote:
> > > Hi Russell,
> > >
> > >
> > > On Wed, Nov 20, 2019 at 6:07 PM Russell King - ARM Linux admin
> > > <[email protected]> wrote:
> > > >
> > > > On Wed, Nov 20, 2019 at 06:02:13PM +0900, Masahiro Yamada wrote:
> > > > > Hi Arnd,
> > > > >
> > > > >
> > > > >
> > > > > On Thu, Nov 14, 2019 at 2:01 AM Russell King - ARM Linux admin
> > > > > <[email protected]> wrote:
> > > > > >
> > > > > > On Wed, Nov 13, 2019 at 02:15:00PM +0100, Geert Uytterhoeven wrote:
> > > > > > > Hi Russell,
> > > > > > >
> > > > > > > On Wed, Nov 13, 2019 at 12:45 PM Russell King - ARM Linux admin
> > > > > > > <[email protected]> wrote:
> > > > > > > > On Wed, Nov 13, 2019 at 08:40:39PM +0900, Masahiro Yamada wrote:
> > > > > > > > > On Tue, Oct 1, 2019 at 11:31 PM Geert Uytterhoeven <[email protected]> wrote:
> > > > > > > > > > On Fri, Sep 6, 2019 at 5:47 PM Arnd Bergmann <[email protected]> wrote:
> > > > > > > > > > > Without the frame pointer enabled, return_address() is an inline
> > > > > > > > > > > function and does not need to be exported, as shown by this warning:
> > > > > > > > > > >
> > > > > > > > > > > WARNING: "return_address" [vmlinux] is a static EXPORT_SYMBOL_GPL
> > > > > > > > > > >
> > > > > > > > > > > Move the EXPORT_SYMBOL_GPL() into the #ifdef as well.
> > > > > > > > > > >
> > > > > > > > > > > Signed-off-by: Arnd Bergmann <[email protected]>
> > > > > > > > > >
> > > > > > > > > > Thanks for your patch!
> > > > > > > > > >
> > > > > > > > > > Tested-by: Geert Uytterhoeven <[email protected]>
> > > > > > > > > >
> > > > > > > > > > > --- a/arch/arm/kernel/return_address.c
> > > > > > > > > > > +++ b/arch/arm/kernel/return_address.c
> > > > > > > > > > > @@ -53,6 +53,7 @@ void *return_address(unsigned int level)
> > > > > > > > > > > return NULL;
> > > > > > > > > > > }
> > > > > > > > > > >
> > > > > > > > > >
> > > > > > > > > > Checkpatch doesn't like the empty line above:
> > > > > > > > > >
> > > > > > > > > > WARNING: EXPORT_SYMBOL(foo); should immediately follow its function/variable
> > > > > > > > > >
> > > > > > > > > > > +EXPORT_SYMBOL_GPL(return_address);
> > > > > > > > > > > +
> > > > > > > > > > > #endif /* if defined(CONFIG_FRAME_POINTER) && !defined(CONFIG_ARM_UNWIND) */
> > > > > > > > > > >
> > > > > > > > > > > -EXPORT_SYMBOL_GPL(return_address);
> > > > > > >
> > > > > > > > > What has happened to this patch?
> > > > > > > > >
> > > > > > > > > I still see this warning.
> > > > > > > >
> > > > > > > > Simple - it got merged, it caused build regressions, it got dropped.
> > > > > > > > A new version is pending me doing another round of patch merging.
> > > > > > >
> > > > > > > I believe that was not Arnd's patch, but Ben Dooks' alternative solution[*]?
> > > > > >
> > > > > > I don't keep track of who did what, sorry.
> > > > >
> > > > >
> > > > > Arnd,
> > > > >
> > > > > I believe this patch is the correct fix.
> > > > > Could you please put it into Russell's patch tracker?
> > > > > ([email protected])
> > > >
> > > > Is there something wrong with:
> > > >
> > > > fb033c95c94c ARM: 8918/2: only build return_address() if needed
> > > >
> > > > I haven't seen any build issues with that.
> > >
> > >
> > > Sorry, I had not checked Ben's patch because you said
> > > "Simple - it got merged, it caused build regressions, it got dropped."
> >
> > That was 8918/1. Ben fixed his patch, and submitted an updated
> > version.
> >
> > > Yup, I've checked it right now,
> > > and it looks good to me.
> > >
> > > But, I do not see that commit in the latest linux-next
> > > (next-20191120).
> > >
> > > Could you really apply it if you have not.
> >
> > It was applied last Friday and was pushed out there and then.
> >
> > $ git ls-remote zeniv | grep for-next
> > 022eb8ae8b5ee8c5c813923c69b5ebb1e9612c4c refs/heads/for-next
> > $ git lg for-next
> > 022eb8ae8b5e ARM: 8938/1: kernel: initialize broadcast hrtimer based
> > clock event device
> > ...
> > fb033c95c94c ARM: 8918/2: only build return_address() if needed
> >
> > I've no idea why linux-next doesn't have it.
>
> Okay, apparently linux-next _does_ have it:
>
> https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/log/arch/arm/kernel/Makefile
>
> so I think you're confused.


My brain was corrupted.

It was my mis-operation of git. I now see it.




--
Best Regards
Masahiro Yamada

2019-11-20 12:47:11

by Masahiro Yamada

[permalink] [raw]
Subject: Re: [PATCH] ARM: don't export unused return_address()

Hi Russell,


On Wed, Nov 20, 2019 at 6:07 PM Russell King - ARM Linux admin
<[email protected]> wrote:
>
> On Wed, Nov 20, 2019 at 06:02:13PM +0900, Masahiro Yamada wrote:
> > Hi Arnd,
> >
> >
> >
> > On Thu, Nov 14, 2019 at 2:01 AM Russell King - ARM Linux admin
> > <[email protected]> wrote:
> > >
> > > On Wed, Nov 13, 2019 at 02:15:00PM +0100, Geert Uytterhoeven wrote:
> > > > Hi Russell,
> > > >
> > > > On Wed, Nov 13, 2019 at 12:45 PM Russell King - ARM Linux admin
> > > > <[email protected]> wrote:
> > > > > On Wed, Nov 13, 2019 at 08:40:39PM +0900, Masahiro Yamada wrote:
> > > > > > On Tue, Oct 1, 2019 at 11:31 PM Geert Uytterhoeven <[email protected]> wrote:
> > > > > > > On Fri, Sep 6, 2019 at 5:47 PM Arnd Bergmann <[email protected]> wrote:
> > > > > > > > Without the frame pointer enabled, return_address() is an inline
> > > > > > > > function and does not need to be exported, as shown by this warning:
> > > > > > > >
> > > > > > > > WARNING: "return_address" [vmlinux] is a static EXPORT_SYMBOL_GPL
> > > > > > > >
> > > > > > > > Move the EXPORT_SYMBOL_GPL() into the #ifdef as well.
> > > > > > > >
> > > > > > > > Signed-off-by: Arnd Bergmann <[email protected]>
> > > > > > >
> > > > > > > Thanks for your patch!
> > > > > > >
> > > > > > > Tested-by: Geert Uytterhoeven <[email protected]>
> > > > > > >
> > > > > > > > --- a/arch/arm/kernel/return_address.c
> > > > > > > > +++ b/arch/arm/kernel/return_address.c
> > > > > > > > @@ -53,6 +53,7 @@ void *return_address(unsigned int level)
> > > > > > > > return NULL;
> > > > > > > > }
> > > > > > > >
> > > > > > >
> > > > > > > Checkpatch doesn't like the empty line above:
> > > > > > >
> > > > > > > WARNING: EXPORT_SYMBOL(foo); should immediately follow its function/variable
> > > > > > >
> > > > > > > > +EXPORT_SYMBOL_GPL(return_address);
> > > > > > > > +
> > > > > > > > #endif /* if defined(CONFIG_FRAME_POINTER) && !defined(CONFIG_ARM_UNWIND) */
> > > > > > > >
> > > > > > > > -EXPORT_SYMBOL_GPL(return_address);
> > > >
> > > > > > What has happened to this patch?
> > > > > >
> > > > > > I still see this warning.
> > > > >
> > > > > Simple - it got merged, it caused build regressions, it got dropped.
> > > > > A new version is pending me doing another round of patch merging.
> > > >
> > > > I believe that was not Arnd's patch, but Ben Dooks' alternative solution[*]?
> > >
> > > I don't keep track of who did what, sorry.
> >
> >
> > Arnd,
> >
> > I believe this patch is the correct fix.
> > Could you please put it into Russell's patch tracker?
> > ([email protected])
>
> Is there something wrong with:
>
> fb033c95c94c ARM: 8918/2: only build return_address() if needed
>
> I haven't seen any build issues with that.


Sorry, I had not checked Ben's patch because you said
"Simple - it got merged, it caused build regressions, it got dropped."


Yup, I've checked it right now,
and it looks good to me.

But, I do not see that commit in the latest linux-next
(next-20191120).

Could you really apply it if you have not.

Thanks!



--
Best Regards
Masahiro Yamada

2019-11-20 12:58:09

by Russell King (Oracle)

[permalink] [raw]
Subject: Re: [PATCH] ARM: don't export unused return_address()

On Wed, Nov 20, 2019 at 09:51:11AM +0000, Russell King - ARM Linux admin wrote:
> On Wed, Nov 20, 2019 at 06:42:52PM +0900, Masahiro Yamada wrote:
> > Hi Russell,
> >
> >
> > On Wed, Nov 20, 2019 at 6:07 PM Russell King - ARM Linux admin
> > <[email protected]> wrote:
> > >
> > > On Wed, Nov 20, 2019 at 06:02:13PM +0900, Masahiro Yamada wrote:
> > > > Hi Arnd,
> > > >
> > > >
> > > >
> > > > On Thu, Nov 14, 2019 at 2:01 AM Russell King - ARM Linux admin
> > > > <[email protected]> wrote:
> > > > >
> > > > > On Wed, Nov 13, 2019 at 02:15:00PM +0100, Geert Uytterhoeven wrote:
> > > > > > Hi Russell,
> > > > > >
> > > > > > On Wed, Nov 13, 2019 at 12:45 PM Russell King - ARM Linux admin
> > > > > > <[email protected]> wrote:
> > > > > > > On Wed, Nov 13, 2019 at 08:40:39PM +0900, Masahiro Yamada wrote:
> > > > > > > > On Tue, Oct 1, 2019 at 11:31 PM Geert Uytterhoeven <[email protected]> wrote:
> > > > > > > > > On Fri, Sep 6, 2019 at 5:47 PM Arnd Bergmann <[email protected]> wrote:
> > > > > > > > > > Without the frame pointer enabled, return_address() is an inline
> > > > > > > > > > function and does not need to be exported, as shown by this warning:
> > > > > > > > > >
> > > > > > > > > > WARNING: "return_address" [vmlinux] is a static EXPORT_SYMBOL_GPL
> > > > > > > > > >
> > > > > > > > > > Move the EXPORT_SYMBOL_GPL() into the #ifdef as well.
> > > > > > > > > >
> > > > > > > > > > Signed-off-by: Arnd Bergmann <[email protected]>
> > > > > > > > >
> > > > > > > > > Thanks for your patch!
> > > > > > > > >
> > > > > > > > > Tested-by: Geert Uytterhoeven <[email protected]>
> > > > > > > > >
> > > > > > > > > > --- a/arch/arm/kernel/return_address.c
> > > > > > > > > > +++ b/arch/arm/kernel/return_address.c
> > > > > > > > > > @@ -53,6 +53,7 @@ void *return_address(unsigned int level)
> > > > > > > > > > return NULL;
> > > > > > > > > > }
> > > > > > > > > >
> > > > > > > > >
> > > > > > > > > Checkpatch doesn't like the empty line above:
> > > > > > > > >
> > > > > > > > > WARNING: EXPORT_SYMBOL(foo); should immediately follow its function/variable
> > > > > > > > >
> > > > > > > > > > +EXPORT_SYMBOL_GPL(return_address);
> > > > > > > > > > +
> > > > > > > > > > #endif /* if defined(CONFIG_FRAME_POINTER) && !defined(CONFIG_ARM_UNWIND) */
> > > > > > > > > >
> > > > > > > > > > -EXPORT_SYMBOL_GPL(return_address);
> > > > > >
> > > > > > > > What has happened to this patch?
> > > > > > > >
> > > > > > > > I still see this warning.
> > > > > > >
> > > > > > > Simple - it got merged, it caused build regressions, it got dropped.
> > > > > > > A new version is pending me doing another round of patch merging.
> > > > > >
> > > > > > I believe that was not Arnd's patch, but Ben Dooks' alternative solution[*]?
> > > > >
> > > > > I don't keep track of who did what, sorry.
> > > >
> > > >
> > > > Arnd,
> > > >
> > > > I believe this patch is the correct fix.
> > > > Could you please put it into Russell's patch tracker?
> > > > ([email protected])
> > >
> > > Is there something wrong with:
> > >
> > > fb033c95c94c ARM: 8918/2: only build return_address() if needed
> > >
> > > I haven't seen any build issues with that.
> >
> >
> > Sorry, I had not checked Ben's patch because you said
> > "Simple - it got merged, it caused build regressions, it got dropped."
>
> That was 8918/1. Ben fixed his patch, and submitted an updated
> version.
>
> > Yup, I've checked it right now,
> > and it looks good to me.
> >
> > But, I do not see that commit in the latest linux-next
> > (next-20191120).
> >
> > Could you really apply it if you have not.
>
> It was applied last Friday and was pushed out there and then.
>
> $ git ls-remote zeniv | grep for-next
> 022eb8ae8b5ee8c5c813923c69b5ebb1e9612c4c refs/heads/for-next
> $ git lg for-next
> 022eb8ae8b5e ARM: 8938/1: kernel: initialize broadcast hrtimer based
> clock event device
> ...
> fb033c95c94c ARM: 8918/2: only build return_address() if needed
>
> I've no idea why linux-next doesn't have it.

Okay, apparently linux-next _does_ have it:

https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/log/arch/arm/kernel/Makefile

so I think you're confused.

--
RMK's Patch system: https://www.armlinux.org.uk/developer/patches/
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