kobject.c changes in -mm

kobject.c changes in -mm

[Christoph Hellwig]

--- linux-2.6.20-rc3/lib/kobject.c      2007-01-01 23:04:49.000000000 -0800
+++ devel/lib/kobject.c 2007-01-04 21:13:21.000000000 -0800
@@ -15,6 +15,8 @@
 #include <linux/module.h>
 #include <linux/stat.h>
 #include <linux/slab.h>
+#include <linux/kallsyms.h>
+#include <asm-generic/sections.h>

+#ifdef CONFIG_X86_32
+static int ptr_in_range(void *ptr, void *start, void *end)
+{
+       /*
+        * This should hopefully get rid of causing warnings
+        * if the architecture did not set one of the section
+        * variables up.
+        */ 
+       if (start >= end)
+               return 0;
+
+       if ((ptr >= start) && (ptr < end))
+               return 1;
+       return 0;
+}      


Can anyone explain WTF is going on here?  Including asm-generic headers
in core code definitly is not okay.  As are random CONFIG_X86_32 ifdefs
in said code.

Re: kobject.c changes in -mm

[Greg KH]

On Mon, Jan 08, 2007 at 01:37:47PM +0000, Christoph Hellwig wrote:
> --- linux-2.6.20-rc3/lib/kobject.c      2007-01-01 23:04:49.000000000 -0800
> +++ devel/lib/kobject.c 2007-01-04 21:13:21.000000000 -0800
> @@ -15,6 +15,8 @@
>  #include <linux/module.h>
>  #include <linux/stat.h>
>  #include <linux/slab.h>
> +#include <linux/kallsyms.h>
> +#include <asm-generic/sections.h>
> 
> +#ifdef CONFIG_X86_32
> +static int ptr_in_range(void *ptr, void *start, void *end)
> +{
> +       /*
> +        * This should hopefully get rid of causing warnings
> +        * if the architecture did not set one of the section
> +        * variables up.
> +        */ 
> +       if (start >= end)
> +               return 0;
> +
> +       if ((ptr >= start) && (ptr < end))
> +               return 1;
> +       return 0;
> +}      
> 
> 
> Can anyone explain WTF is going on here?  Including asm-generic headers
> in core code definitly is not okay.  As are random CONFIG_X86_32 ifdefs
> in said code.

It's a hack for debugging.  See the full patch at:
	http://www.kernel.org/pub/linux/kernel/people/gregkh/gregkh-2.6/patches/driver/warn-when-statically-allocated-kobjects-are-used.patch

It is never going to go to mainline, due to the arch-specific hacks as
you have noted.  But is good to have for debugging and getting error
reports from users of -mm.

thanks,

greg k-h

Re: kobject.c changes in -mm

[Frederik Deweerdt]

On Mon, Jan 08, 2007 at 11:09:42AM -0800, Greg KH wrote:
> On Mon, Jan 08, 2007 at 01:37:47PM +0000, Christoph Hellwig wrote:
> > --- linux-2.6.20-rc3/lib/kobject.c      2007-01-01 23:04:49.000000000 -0800
> > +++ devel/lib/kobject.c 2007-01-04 21:13:21.000000000 -0800
> > @@ -15,6 +15,8 @@
> >  #include <linux/module.h>
> >  #include <linux/stat.h>
> >  #include <linux/slab.h>
> > +#include <linux/kallsyms.h>
> > +#include <asm-generic/sections.h>
> > 
> > +#ifdef CONFIG_X86_32
> > +static int ptr_in_range(void *ptr, void *start, void *end)
> > +{
> > +       /*
> > +        * This should hopefully get rid of causing warnings
> > +        * if the architecture did not set one of the section
> > +        * variables up.
> > +        */ 
> > +       if (start >= end)
> > +               return 0;
> > +
> > +       if ((ptr >= start) && (ptr < end))
> > +               return 1;
> > +       return 0;
> > +}      
> > 
> > 
> > Can anyone explain WTF is going on here?  Including asm-generic headers
> > in core code definitly is not okay.  As are random CONFIG_X86_32 ifdefs
> > in said code.
> 
> It's a hack for debugging.  See the full patch at:
> 	http://www.kernel.org/pub/linux/kernel/people/gregkh/gregkh-2.6/patches/driver/warn-when-statically-allocated-kobjects-are-used.patch
> 
> It is never going to go to mainline, due to the arch-specific hacks as
> you have noted.  But is good to have for debugging and getting error
> reports from users of -mm.
> 
Could a CONFIG_{MM,HACK}  option be added for this kind of hacks? It could
help clarify what the aim of the code is.

Regards,
Frederik

Re: kobject.c changes in -mm

[Greg KH]

On Mon, Jan 08, 2007 at 07:25:07PM +0000, Frederik Deweerdt wrote:
> On Mon, Jan 08, 2007 at 11:09:42AM -0800, Greg KH wrote:
> > On Mon, Jan 08, 2007 at 01:37:47PM +0000, Christoph Hellwig wrote:
> > > --- linux-2.6.20-rc3/lib/kobject.c      2007-01-01 23:04:49.000000000 -0800
> > > +++ devel/lib/kobject.c 2007-01-04 21:13:21.000000000 -0800
> > > @@ -15,6 +15,8 @@
> > >  #include <linux/module.h>
> > >  #include <linux/stat.h>
> > >  #include <linux/slab.h>
> > > +#include <linux/kallsyms.h>
> > > +#include <asm-generic/sections.h>
> > > 
> > > +#ifdef CONFIG_X86_32
> > > +static int ptr_in_range(void *ptr, void *start, void *end)
> > > +{
> > > +       /*
> > > +        * This should hopefully get rid of causing warnings
> > > +        * if the architecture did not set one of the section
> > > +        * variables up.
> > > +        */ 
> > > +       if (start >= end)
> > > +               return 0;
> > > +
> > > +       if ((ptr >= start) && (ptr < end))
> > > +               return 1;
> > > +       return 0;
> > > +}      
> > > 
> > > 
> > > Can anyone explain WTF is going on here?  Including asm-generic headers
> > > in core code definitly is not okay.  As are random CONFIG_X86_32 ifdefs
> > > in said code.
> > 
> > It's a hack for debugging.  See the full patch at:
> > 	http://www.kernel.org/pub/linux/kernel/people/gregkh/gregkh-2.6/patches/driver/warn-when-statically-allocated-kobjects-are-used.patch
> > 
> > It is never going to go to mainline, due to the arch-specific hacks as
> > you have noted.  But is good to have for debugging and getting error
> > reports from users of -mm.
> > 
> Could a CONFIG_{MM,HACK}  option be added for this kind of hacks? It could
> help clarify what the aim of the code is.

How would that help here?  I don't think we want to #ifdef all patches
in the -mm tree that are of this type, that would be a bit nasty.

thanks,

greg k-h

Re: kobject.c changes in -mm

[Frederik Deweerdt]

On Mon, Jan 08, 2007 at 12:31:56PM -0800, Greg KH wrote:
> On Mon, Jan 08, 2007 at 07:25:07PM +0000, Frederik Deweerdt wrote:
> > On Mon, Jan 08, 2007 at 11:09:42AM -0800, Greg KH wrote:
> > > On Mon, Jan 08, 2007 at 01:37:47PM +0000, Christoph Hellwig wrote:
> > > > --- linux-2.6.20-rc3/lib/kobject.c      2007-01-01 23:04:49.000000000 -0800
> > > > +++ devel/lib/kobject.c 2007-01-04 21:13:21.000000000 -0800
> > > > @@ -15,6 +15,8 @@
> > > >  #include <linux/module.h>
> > > >  #include <linux/stat.h>
> > > >  #include <linux/slab.h>
> > > > +#include <linux/kallsyms.h>
> > > > +#include <asm-generic/sections.h>
> > > > 
> > > > +#ifdef CONFIG_X86_32
> > > > +static int ptr_in_range(void *ptr, void *start, void *end)
> > > > +{
> > > > +       /*
> > > > +        * This should hopefully get rid of causing warnings
> > > > +        * if the architecture did not set one of the section
> > > > +        * variables up.
> > > > +        */ 
> > > > +       if (start >= end)
> > > > +               return 0;
> > > > +
> > > > +       if ((ptr >= start) && (ptr < end))
> > > > +               return 1;
> > > > +       return 0;
> > > > +}      
> > > > 
> > > > 
> > > > Can anyone explain WTF is going on here?  Including asm-generic headers
> > > > in core code definitly is not okay.  As are random CONFIG_X86_32 ifdefs
> > > > in said code.
> > > 
> > > It's a hack for debugging.  See the full patch at:
> > > 	http://www.kernel.org/pub/linux/kernel/people/gregkh/gregkh-2.6/patches/driver/warn-when-statically-allocated-kobjects-are-used.patch
> > > 
> > > It is never going to go to mainline, due to the arch-specific hacks as
> > > you have noted.  But is good to have for debugging and getting error
> > > reports from users of -mm.
> > > 
> > Could a CONFIG_{MM,HACK}  option be added for this kind of hacks? It could
> > help clarify what the aim of the code is.
> 
> How would that help here?  I don't think we want to #ifdef all patches
> in the -mm tree that are of this type, that would be a bit nasty.
I see how this would be messy, but this could help advertising the fact
that the patch is not going to mainline, if only because mainline wouldn't
have that CONFIG_HACK thing.
Another alternative would a mm-only- prefix to the name of the patches,
a simple grep in broken-out would the be enough...

Regards,
Frederik
> thanks,
> 
> greg k-h
> 

Re: kobject.c changes in -mm

[Greg KH]

On Mon, Jan 08, 2007 at 09:56:32PM +0000, Frederik Deweerdt wrote:
> On Mon, Jan 08, 2007 at 12:31:56PM -0800, Greg KH wrote:
> > On Mon, Jan 08, 2007 at 07:25:07PM +0000, Frederik Deweerdt wrote:
> > > On Mon, Jan 08, 2007 at 11:09:42AM -0800, Greg KH wrote:
> > > > On Mon, Jan 08, 2007 at 01:37:47PM +0000, Christoph Hellwig wrote:
> > > > > --- linux-2.6.20-rc3/lib/kobject.c      2007-01-01 23:04:49.000000000 -0800
> > > > > +++ devel/lib/kobject.c 2007-01-04 21:13:21.000000000 -0800
> > > > > @@ -15,6 +15,8 @@
> > > > >  #include <linux/module.h>
> > > > >  #include <linux/stat.h>
> > > > >  #include <linux/slab.h>
> > > > > +#include <linux/kallsyms.h>
> > > > > +#include <asm-generic/sections.h>
> > > > > 
> > > > > +#ifdef CONFIG_X86_32
> > > > > +static int ptr_in_range(void *ptr, void *start, void *end)
> > > > > +{
> > > > > +       /*
> > > > > +        * This should hopefully get rid of causing warnings
> > > > > +        * if the architecture did not set one of the section
> > > > > +        * variables up.
> > > > > +        */ 
> > > > > +       if (start >= end)
> > > > > +               return 0;
> > > > > +
> > > > > +       if ((ptr >= start) && (ptr < end))
> > > > > +               return 1;
> > > > > +       return 0;
> > > > > +}      
> > > > > 
> > > > > 
> > > > > Can anyone explain WTF is going on here?  Including asm-generic headers
> > > > > in core code definitly is not okay.  As are random CONFIG_X86_32 ifdefs
> > > > > in said code.
> > > > 
> > > > It's a hack for debugging.  See the full patch at:
> > > > 	http://www.kernel.org/pub/linux/kernel/people/gregkh/gregkh-2.6/patches/driver/warn-when-statically-allocated-kobjects-are-used.patch
> > > > 
> > > > It is never going to go to mainline, due to the arch-specific hacks as
> > > > you have noted.  But is good to have for debugging and getting error
> > > > reports from users of -mm.
> > > > 
> > > Could a CONFIG_{MM,HACK}  option be added for this kind of hacks? It could
> > > help clarify what the aim of the code is.
> > 
> > How would that help here?  I don't think we want to #ifdef all patches
> > in the -mm tree that are of this type, that would be a bit nasty.
> I see how this would be messy, but this could help advertising the fact
> that the patch is not going to mainline, if only because mainline wouldn't
> have that CONFIG_HACK thing.
> Another alternative would a mm-only- prefix to the name of the patches,
> a simple grep in broken-out would the be enough...

That's a good idea, I can rename some of these patches...

thanks,

greg k-h