Commit Graph

71 Commits

Author SHA1 Message Date
Roland McGrath
16e48e7e79 x86 vDSO: makefile cleanup
This cleans up the arch/x86/vdso/Makefile rules for vdso.so to
share more code with the vdso32-*.so rules and remove old cruft.

Signed-off-by: Roland McGrath <roland@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-01-30 13:30:44 +01:00
Roland McGrath
69d0627a7f x86 vDSO: reorder vdso32 code
This reorders the code in the 32-bit vDSO images to put the signal
trampolines first and __kernel_vsyscall after them.  The order does
not matter to userland, it just uses what AT_SYSINFO or e_entry
says.  Since the signal trampolines are the same size in both
versions of the vDSO, putting them first is the simplest way to get
the addresses to line up.  This makes it work to use a more compact
layout for the vDSO.

Signed-off-by: Roland McGrath <roland@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-01-30 13:30:44 +01:00
Roland McGrath
af65d64845 x86 vDSO: consolidate vdso32
This makes x86_64's ia32 emulation support share the sources used in the
32-bit kernel for the 32-bit vDSO and much of its setup code.

The 32-bit vDSO mapping now behaves the same on x86_64 as on native 32-bit.
The abi.syscall32 sysctl on x86_64 now takes the same values that
vm.vdso_enabled takes on the 32-bit kernel.  That is, 1 means a randomized
vDSO location, 2 means the fixed old address.  The CONFIG_COMPAT_VDSO
option is now available to make this the default setting, the same meaning
it has for the 32-bit kernel.  (This does not affect the 64-bit vDSO.)

The argument vdso32=[012] can be used on both 32-bit and 64-bit kernels to
set this paramter at boot time.  The vdso=[012] argument still does this
same thing on the 32-bit kernel.

Signed-off-by: Roland McGrath <roland@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-01-30 13:30:43 +01:00
Roland McGrath
00f8b1bc0e x86 vDSO: ia32 vdso32-syscall build
This puts the syscall version of the 32-bit vDSO in arch/x86/vdso/vdso32/
for 64-bit IA32 support.  This is not used yet, but it paves the way for
consolidating the 32-bit vDSO source and build logic all in one place.

Signed-off-by: Roland McGrath <roland@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-01-30 13:30:43 +01:00
Roland McGrath
0aa97fb226 x86 vDSO: ia32_sysenter_target
This harmonizes the name for the entry point from the 32-bit sysenter
instruction across 32-bit and 64-bit kernels.

Signed-off-by: Roland McGrath <roland@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-01-30 13:30:43 +01:00
Roland McGrath
f288f32dc5 x86 vDSO: vdso32 setup
This moves arch/x86/kernel/sysenter_32.c to arch/x86/vdso/vdso32-setup.c,
keeping all the code relating only to vDSO magic in the vdso/ subdirectory.
This is a pure renaming, but it paves the way to consolidating the code for
dealing with 32-bit vDSOs across CONFIG_X86_32 and CONFIG_IA32_EMULATION.

Signed-off-by: Roland McGrath <roland@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-01-30 13:30:42 +01:00
Roland McGrath
6c3652efca x86 vDSO: i386 vdso32
This makes the i386 kernel use the new vDSO build in arch/x86/vdso/vdso32/
to replace the old one from arch/x86/kernel/.

Signed-off-by: Roland McGrath <roland@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-01-30 13:30:42 +01:00
Roland McGrath
0249c9c1e7 x86 vDSO: vdso32 build
This builds the 32-bit vDSO images in the arch/x86/vdso subdirectory.
Nothing uses the images yet, but this paves the way for consolidating
the vDSO build logic all in one place.  The new images use a linker
script sharing the layout parts from vdso-layout.lds.S with the 64-bit
vDSO.  A new vdso32-syms.lds is generated in the style of vdso-syms.lds.

Signed-off-by: Roland McGrath <roland@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-01-30 13:30:42 +01:00
Roland McGrath
0c2f51a7d2 x86 vDSO: arch/x86/vdso/vdso32
This moves the i386 vDSO sources into arch/x86/vdso/vdso32/, a
new directory.  This patch is a pure renaming, but paves the way
for consolidating the vDSO build logic.

Signed-off-by: Roland McGrath <roland@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-01-30 13:30:42 +01:00
Roland McGrath
f6b46ebf90 x86 vDSO: new layout
This revamps the vDSO linker script to lay things out with the best
packing of the data and good, separate alignment of the code.  The
rigid layout using VDSO_TEXT_OFFSET no longer matters to the kernel.
I've moved the layout parts of the linker script into a new include
file, vdso-layout.lds.S; this is in preparation for sharing the script
for the 32-bit vDSO builds too.

Signed-off-by: Roland McGrath <roland@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-01-30 13:30:41 +01:00
Roland McGrath
2b9c97e161 x86 vDSO: remove vdso-syms.o
Get rid of vdso-syms.o from the kernel link.  We don't need it any more.

Signed-off-by: Roland McGrath <roland@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-01-30 13:30:41 +01:00
Roland McGrath
7f3646aa16 x86 vDSO: use vdso-syms.lds
This patch changes the kernel's references to addresses in the vDSO image
to be based on the symbols defined by vdso-syms.lds instead of the old
vdso-syms.o symbols.  This is all wrapped up in a macro defined by the new
asm-x86/vdso.h header; that's the only place in the kernel source that has
to know the details of the scheme for getting vDSO symbol values.

Signed-off-by: Roland McGrath <roland@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-01-30 13:30:41 +01:00
Roland McGrath
5b93049337 x86 vDSO: generate vdso-syms.lds
This patch adds a new way of extracting symbols from the built vDSO image.
This is much simpler and less fragile than using ld -R; it removes the
need to control the DSO layout quite so exactly.  I was clearly unduly
distracted by clever ld uses when I did the original vDSO implementation.

Signed-off-by: Roland McGrath <roland@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-01-30 13:30:40 +01:00
Lucas Woods
201c19948b x86: remove duplicate includes
Signed-off-by: Lucas Woods <woodzy@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-01-30 13:30:32 +01:00
Ingo Molnar
4307d1e5ad x86: ignore the sys_getcpu() tcache parameter
dont use the vgetcpu tcache - it's causing problems with tasks
migrating, they'll see the old cache up to a jiffy after the
migration, further increasing the costs of the migration.

In the worst case they see a complete bogus information from
the tcache, when a sys_getcpu() call "invalidated" the cache
info by incrementing the jiffies _and_ the cpuid info in the
cache and the following vdso_getcpu() call happens after
vdso_jiffies have been incremented.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Ulrich Drepper <drepper@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2007-11-17 16:27:00 +01:00
Sam Ravnborg
d746d647f3 x86: do not use $(ARCH) when not needed
For x86 ARCH may say i386 or x86_64 and soon x86.
Rely on CONFIG_X64_32 to select between 32/64 or just
hardcode the value as appropriate.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
2007-11-12 21:02:20 +01:00
Roland McGrath
c65916fe35 x86: vdso linker script cleanup
I can't see the reason ".  = VDSO_PRELINK + 0x900;" was ever there in
the linker script for the x86_64 vDSO.  I can't find anything that
depends on this magic offset, or that should care at all about the
particular location of of the .data section (all from vvar.c) in the
vDSO image.  If it is really desireable to place .data at 0x900, then it
should be after all the other sections so they fill in the space up to
0x900.

This removes the 0x900 magic and cleans up the output sections generally
in the vDSO linker script.  This saves a few hundred bytes in the size
of the vDSO file, bringing it back well under 4kb total so that its vma
only needs one page.

Signed-off-by: Roland McGrath <roland@redhat.com>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2007-10-17 20:17:06 +02:00
Roland McGrath
06f99ac87e x86: vdso put vars in rodata
This adds a const to the definitions vvar.c makes, so that the vdso_*
variables go into .rodata instead of .data.  This is essentially a
cosmetic change, just giving the section headers in the vDSO file more
pleasing flags. These variables are read-only from the perspective of
the vDSO itself and user mode, even though the contents of the DSO image
were adjusted at boot.

Signed-off-by: Roland McGrath <roland@redhat.com>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2007-10-17 20:16:43 +02:00
Roland McGrath
f79eb83b3a x86: Install unstripped copy of 64bit vdso to disk
This keeps an unstripped copy of the 64bit vDSO images built before they are
stripped and embedded in the kernel.  The unstripped copies get installed
in $(MODLIB)/vdso/ by "make install" (or you can explicitly use the
subtarget "make vdso_install").  These files can be useful when they
contain source-level debugging information.

[ tglx: arch/x86 adaptation ]

Signed-off-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2007-10-17 20:15:20 +02:00
Sam Ravnborg
a0f97e06a4 kbuild: enable 'make CFLAGS=...' to add additional options to CC
The variable CFLAGS is a wellknown variable and the usage by
kbuild may result in unexpected behaviour.
On top of that several people over time has asked for a way to
pass in additional flags to gcc.

This patch replace use of CFLAGS with KBUILD_CFLAGS all over the
tree and enabling one to use:
make CFLAGS=...
to specify additional gcc commandline options.

One usecase is when trying to find gcc bugs but other
use cases has been requested too.

Patch was tested on following architectures:
alpha, arm, i386, x86_64, mips, sparc, sparc64, ia64, m68k

Test was simple to do a defconfig build, apply the patch and check
that nothing got rebuild.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2007-10-14 22:21:35 +02:00
Thomas Gleixner
7648b1330c x86_64: move vdso
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2007-10-11 11:17:10 +02:00