linux/arch
Jeff Dike 536788fe2d uml: runtime host VMSPLIT detection
Calculate TASK_SIZE at run-time by figuring out the host's VMSPLIT - this is
needed on i386 if UML is to run on hosts with varying VMSPLITs without
recompilation.

TASK_SIZE is now defined in terms of a variable, task_size.  This gets rid of
an include of pgtable.h from processor.h, which can cause include loops.

On i386, task_size is calculated early in boot by probing the address space in
a binary search to figure out where the boundary between usable and non-usable
memory is.  This tries to make sure that a page that is considered to be in
userspace is, or can be made, read-write.  I'm concerned about a system-global
VDSO page in kernel memory being hit and considered to be a userspace page.

On x86_64, task_size is just the old value of CONFIG_TOP_ADDR.

A bunch of config variable are gone now.  CONFIG_TOP_ADDR is directly replaced
by TASK_SIZE.  NEST_LEVEL is gone since the relocation of the stubs makes it
irrelevant.  All the HOST_VMSPLIT stuff is gone.  All references to these in
arch/um/Makefile are also gone.

I noticed and fixed a missing extern in os.h when adding os_get_task_size.

Note: This has been revised to fix the 32-bit UML on 64-bit host bug that
Miklos ran into.

Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Cc: Miklos Szeredi <miklos@szeredi.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-08 09:22:42 -08:00
..
alpha avoid overflows in kernel/time.c 2008-02-08 09:22:39 -08:00
arm aout: remove unnecessary inclusions of {asm, linux}/a.out.h 2008-02-08 09:22:30 -08:00
avr32 Basic PWM driver for AVR32 and AT91 2008-02-08 09:22:38 -08:00
blackfin procfs: constify function pointer tables 2008-02-08 09:22:38 -08:00
cris avoid overflows in kernel/time.c 2008-02-08 09:22:39 -08:00
frv CONFIG_HIGHPTE vs. sub-page page tables. 2008-02-08 09:22:42 -08:00
h8300 avoid overflows in kernel/time.c 2008-02-08 09:22:39 -08:00
ia64 time: fix typo in comments 2008-02-08 09:22:29 -08:00
m32r avoid overflows in kernel/time.c 2008-02-08 09:22:39 -08:00
m68k avoid overflows in kernel/time.c 2008-02-08 09:22:39 -08:00
m68knommu avoid overflows in kernel/time.c 2008-02-08 09:22:39 -08:00
mips MIPS: Mark all but i8259 interrupts as no-probe. 2008-02-08 09:22:42 -08:00
mn10300 mn10300: add platform MTD support for the ASB2303 board 2008-02-08 09:22:30 -08:00
parisc procfs: constify function pointer tables 2008-02-08 09:22:38 -08:00
powerpc CONFIG_HIGHPTE vs. sub-page page tables. 2008-02-08 09:22:42 -08:00
ppc CONFIG_HIGHPTE vs. sub-page page tables. 2008-02-08 09:22:42 -08:00
s390 CONFIG_HIGHPTE vs. sub-page page tables. 2008-02-08 09:22:42 -08:00
sh Fix container_of() usage 2008-02-08 09:22:32 -08:00
sparc CONFIG_HIGHPTE vs. sub-page page tables. 2008-02-08 09:22:42 -08:00
sparc64 misc: removal of final callers using fastcall 2008-02-08 09:22:31 -08:00
um uml: runtime host VMSPLIT detection 2008-02-08 09:22:42 -08:00
v850 avoid overflows in kernel/time.c 2008-02-08 09:22:39 -08:00
x86 CONFIG_HIGHPTE vs. sub-page page tables. 2008-02-08 09:22:42 -08:00
xtensa avoid overflows in kernel/time.c 2008-02-08 09:22:39 -08:00
.gitignore arch: Ignore arch/i386 and arch/x86_64 2008-01-19 21:29:39 -08:00
Kconfig Move Kconfig.instrumentation to arch/Kconfig and init/Kconfig 2008-02-03 08:58:08 +01:00