Re: 2G memory split

[Kirill Korotaev <dev@sw.ru>]

> > +#if defined(CONFIG_DEFAULT_3G)
> > +#define __PAGE_OFFSET_RAW	(0xC0000000)
> > +#elif defined(CONFIG_DEFAULT_3G_OPT)
> > +#define	__PAGE_OFFSET_RAW	(0xB0000000)
> > +#elif defined(CONFIG_DEFAULT_2G)
> > +#define __PAGE_OFFSET_RAW	(0x78000000)
> > +#elif defined(CONFIG_DEFAULT_1G)
> > +#define __PAGE_OFFSET_RAW	(0x40000000)
> > +#else
> > +#error "Bad user/kernel offset"
> > +#endif
> > +
> >  #ifdef __ASSEMBLY__
> > -#define __PAGE_OFFSET		(0xC0000000)
> > +#define __PAGE_OFFSET		__PAGE_OFFSET_RAW
> >  #define __PHYSICAL_START	CONFIG_PHYSICAL_START
> >  #else
> > -#define __PAGE_OFFSET		(0xC0000000UL)
> > +#define __PAGE_OFFSET		((unsigned long)__PAGE_OFFSET_RAW)
> >  #define __PHYSICAL_START	((unsigned long)CONFIG_PHYSICAL_START)
> >  #endif
> >  #define __KERNEL_START		(__PAGE_OFFSET + __PHYSICAL_START)
>
> Changing PAGE_OFFSET this way would break at least Valgrind (the latest
> release 3.1.0 by default is statically linked at address 0xb0000000, and
> PIE support does not seem to be present in that release).  I remember
> that similar changes were also breaking Lisp implementations (cmucl,
> sbcl), however, I am not really sure about this.
it also breaks some java versions, so we use 3:4 Gb split in OpenVZ, but 
redhat still uses 4:4 in enterprise version, so number of such 
applications should decrease :)

Thanks,
Kirill
-
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/