Pull x86 cleanups from Peter Anvin:
"The biggest textual change is the cleanup to use symbolic constants
for x86 trap values.
The only *functional* change and the reason for the x86/x32 dependency
is the move of is_ia32_task() into <asm/thread_info.h> so that it can
be used in other code that needs to understand if a system call comes
from the compat entry point (and therefore uses i386 system call
numbers) or not. One intended user for that is the BPF system call
filter. Moving it out of <asm/compat.h> means we can define it
unconditionally, returning always true on i386."
* 'x86-cleanups-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86: Move is_ia32_task to asm/thread_info.h from asm/compat.h
x86: Rename trap_no to trap_nr in thread_struct
x86: Use enum instead of literals for trap values
Pull x32 support for x86-64 from Ingo Molnar:
"This tree introduces the X32 binary format and execution mode for x86:
32-bit data space binaries using 64-bit instructions and 64-bit kernel
syscalls.
This allows applications whose working set fits into a 32 bits address
space to make use of 64-bit instructions while using a 32-bit address
space with shorter pointers, more compressed data structures, etc."
Fix up trivial context conflicts in arch/x86/{Kconfig,vdso/vma.c}
* 'x86-x32-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (71 commits)
x32: Fix alignment fail in struct compat_siginfo
x32: Fix stupid ia32/x32 inversion in the siginfo format
x32: Add ptrace for x32
x32: Switch to a 64-bit clock_t
x32: Provide separate is_ia32_task() and is_x32_task() predicates
x86, mtrr: Use explicit sizing and padding for the 64-bit ioctls
x86/x32: Fix the binutils auto-detect
x32: Warn and disable rather than error if binutils too old
x32: Only clear TIF_X32 flag once
x32: Make sure TS_COMPAT is cleared for x32 tasks
fs: Remove missed ->fds_bits from cessation use of fd_set structs internally
fs: Fix close_on_exec pointer in alloc_fdtable
x32: Drop non-__vdso weak symbols from the x32 VDSO
x32: Fix coding style violations in the x32 VDSO code
x32: Add x32 VDSO support
x32: Allow x32 to be configured
x32: If configured, add x32 system calls to system call tables
x32: Handle process creation
x32: Signal-related system calls
x86: Add #ifdef CONFIG_COMPAT to <asm/sys_ia32.h>
...
Fix a stray ! which flipped the sense if we were generating a signal
frame for ia32 vs. x32.
Introduced in:
e7084fd5 x32: Switch to a 64-bit clock_t
Reported-by: H. J. Lu <hjl.tools@gmail.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Cc: Gregory M. Lueck <gregory.m.lueck@intel.com>
Link: http://lkml.kernel.org/r/1329696488-16970-1-git-send-email-hpa@zytor.com
There are precedences of trap number being referred to as
trap_nr. However thread struct refers trap number as trap_no.
Change it to trap_nr.
Also use enum instead of left-over literals for trap values.
This is pure cleanup, no functional change intended.
Suggested-by: Ingo Molnar <mingo@eltu.hu>
Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Jim Keniston <jkenisto@linux.vnet.ibm.com>
Cc: Linux-mm <linux-mm@kvack.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20120312092555.5379.942.sendpatchset@srdronam.in.ibm.com
[ Fixed the math-emu build ]
Signed-off-by: Ingo Molnar <mingo@elte.hu>
clock_t is used mainly to give the number of jiffies a certain process
has burned. It is entirely feasible for a long-running process to
consume more than 2^32 jiffies especially in a multiprocess system.
As such, switch to a 64-bit clock_t for x32, just as we already
switched to a 64-bit time_t.
clock_t is only used in a handful of places, and as such it is really
not a very significant change. The one that has the biggest impact is
in struct siginfo, but since the *size* of struct siginfo doesn't
change (it is padded to the hilt) it is fairly easy to make this a
localized change.
This also gets rid of sys_x32_times, however since this is a pretty
late change don't compactify the system call numbers; we can reuse
system call slot 521 next time we need an x32 system call.
Reported-by: Gregory M. Lueck <gregory.m.lueck@intel.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Cc: H. J. Lu <hjl.tools@gmail.com>
Link: http://lkml.kernel.org/r/1329696488-16970-1-git-send-email-hpa@zytor.com
While various modules include <asm/i387.h> to get access to things we
actually *intend* for them to use, most of that header file was really
pretty low-level internal stuff that we really don't want to expose to
others.
So split the header file into two: the small exported interfaces remain
in <asm/i387.h>, while the internal definitions that are only used by
core architecture code are now in <asm/fpu-internal.h>.
The guiding principle for this was to expose functions that we export to
modules, and leave them in <asm/i387.h>, while stuff that is used by
task switching or was marked GPL-only is in <asm/fpu-internal.h>.
The fpu-internal.h file could be further split up too, especially since
arch/x86/kvm/ uses some of the remaining stuff for its module. But that
kvm usage should probably be abstracted out a bit, and at least now the
internal FPU accessor functions are much more contained. Even if it
isn't perhaps as contained as it _could_ be.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/alpine.LFD.2.02.1202211340330.5354@i5.linux-foundation.org
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
There are some definitions which are duplicated between
kernel/signal.c and ia32/ia32_signal.c; move them to a common header
file.
Rather than adding stuff to existing header files which contain data
structures, create a new header file; hence the slightly odd name
("all the good ones were taken.")
Note: nothing relied on signal_fault() being defined in
<asm/ptrace.h>.
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
sys32_sigsuspend() and sys32_*sigreturn() change ->blocked directly.
This is not correct, see the changelog in e6fa16ab
"signal: sigprocmask() should do retarget_shared_pending()"
Change them to use set_current_blocked().
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Link: http://lkml.kernel.org/r/20110710192724.GA31755@redhat.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Impact: use new framework
Use {get|put}_user_try, catch, and _ex in arch/x86/ia32/ia32_signal.c.
Note: this patch contains "WARNING: line over 80 characters", because when
introducing new block I insert an indent to avoid mistakes by edit.
Signed-off-by: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Impact: cleanup, avoid 44 sparse warnings, new file asm/sys_ia32.h
Fixes following sparse warnings:
CHECK arch/x86/ia32/sys_ia32.c
arch/x86/ia32/sys_ia32.c:53:17: warning: symbol 'sys32_truncate64' was not declared. Should it be static?
arch/x86/ia32/sys_ia32.c:60:17: warning: symbol 'sys32_ftruncate64' was not declared. Should it be static?
arch/x86/ia32/sys_ia32.c:98:17: warning: symbol 'sys32_stat64' was not declared. Should it be static?
arch/x86/ia32/sys_ia32.c:109:17: warning: symbol 'sys32_lstat64' was not declared. Should it be static?
arch/x86/ia32/sys_ia32.c:119:17: warning: symbol 'sys32_fstat64' was not declared. Should it be static?
arch/x86/ia32/sys_ia32.c:128:17: warning: symbol 'sys32_fstatat' was not declared. Should it be static?
arch/x86/ia32/sys_ia32.c:164:17: warning: symbol 'sys32_mmap' was not declared. Should it be static?
arch/x86/ia32/sys_ia32.c:195:17: warning: symbol 'sys32_mprotect' was not declared. Should it be static?
arch/x86/ia32/sys_ia32.c:201:17: warning: symbol 'sys32_pipe' was not declared. Should it be static?
arch/x86/ia32/sys_ia32.c:215:17: warning: symbol 'sys32_rt_sigaction' was not declared. Should it be static?
arch/x86/ia32/sys_ia32.c:291:17: warning: symbol 'sys32_sigaction' was not declared. Should it be static?
arch/x86/ia32/sys_ia32.c:330:17: warning: symbol 'sys32_rt_sigprocmask' was not declared. Should it be static?
arch/x86/ia32/sys_ia32.c:370:17: warning: symbol 'sys32_alarm' was not declared. Should it be static?
arch/x86/ia32/sys_ia32.c:383:17: warning: symbol 'sys32_old_select' was not declared. Should it be static?
arch/x86/ia32/sys_ia32.c:393:17: warning: symbol 'sys32_waitpid' was not declared. Should it be static?
arch/x86/ia32/sys_ia32.c:401:17: warning: symbol 'sys32_sysfs' was not declared. Should it be static?
arch/x86/ia32/sys_ia32.c:406:17: warning: symbol 'sys32_sched_rr_get_interval' was not declared. Should it be static?
arch/x86/ia32/sys_ia32.c:421:17: warning: symbol 'sys32_rt_sigpending' was not declared. Should it be static?
arch/x86/ia32/sys_ia32.c:445:17: warning: symbol 'sys32_rt_sigqueueinfo' was not declared. Should it be static?
arch/x86/ia32/sys_ia32.c:472:17: warning: symbol 'sys32_sysctl' was not declared. Should it be static?
arch/x86/ia32/sys_ia32.c:517:17: warning: symbol 'sys32_pread' was not declared. Should it be static?
arch/x86/ia32/sys_ia32.c:524:17: warning: symbol 'sys32_pwrite' was not declared. Should it be static?
arch/x86/ia32/sys_ia32.c:532:17: warning: symbol 'sys32_personality' was not declared. Should it be static?
arch/x86/ia32/sys_ia32.c:545:17: warning: symbol 'sys32_sendfile' was not declared. Should it be static?
arch/x86/ia32/sys_ia32.c:565:17: warning: symbol 'sys32_mmap2' was not declared. Should it be static?
arch/x86/ia32/sys_ia32.c:589:17: warning: symbol 'sys32_olduname' was not declared. Should it be static?
arch/x86/ia32/sys_ia32.c:626:6: warning: symbol 'sys32_uname' was not declared. Should it be static?
arch/x86/ia32/sys_ia32.c:641:6: warning: symbol 'sys32_ustat' was not declared. Should it be static?
arch/x86/ia32/sys_ia32.c:663:17: warning: symbol 'sys32_execve' was not declared. Should it be static?
arch/x86/ia32/sys_ia32.c:678:17: warning: symbol 'sys32_clone' was not declared. Should it be static?
arch/x86/ia32/sys_ia32.c:693:6: warning: symbol 'sys32_lseek' was not declared. Should it be static?
arch/x86/ia32/sys_ia32.c:698:6: warning: symbol 'sys32_kill' was not declared. Should it be static?
arch/x86/ia32/sys_ia32.c:703:6: warning: symbol 'sys32_fadvise64_64' was not declared. Should it be static?
arch/x86/ia32/sys_ia32.c:712:6: warning: symbol 'sys32_vm86_warning' was not declared. Should it be static?
arch/x86/ia32/sys_ia32.c:726:6: warning: symbol 'sys32_lookup_dcookie' was not declared. Should it be static?
arch/x86/ia32/sys_ia32.c:732:20: warning: symbol 'sys32_readahead' was not declared. Should it be static?
arch/x86/ia32/sys_ia32.c:738:17: warning: symbol 'sys32_sync_file_range' was not declared. Should it be static?
arch/x86/ia32/sys_ia32.c:746:17: warning: symbol 'sys32_fadvise64' was not declared. Should it be static?
arch/x86/ia32/sys_ia32.c:753:17: warning: symbol 'sys32_fallocate' was not declared. Should it be static?
CHECK arch/x86/ia32/ia32_signal.c
arch/x86/ia32/ia32_signal.c:126:17: warning: symbol 'sys32_sigsuspend' was not declared. Should it be static?
arch/x86/ia32/ia32_signal.c:141:17: warning: symbol 'sys32_sigaltstack' was not declared. Should it be static?
arch/x86/ia32/ia32_signal.c:249:17: warning: symbol 'sys32_sigreturn' was not declared. Should it be static?
arch/x86/ia32/ia32_signal.c:279:17: warning: symbol 'sys32_rt_sigreturn' was not declared. Should it be static?
CHECK arch/x86/ia32/ipc32.c
arch/x86/ia32/ipc32.c:12:17: warning: symbol 'sys32_ipc' was not declared. Should it be static?
Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: cleanup
No need to declare do_signal().
Signed-off-by: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: cleanup
Use __USER32_DS instead of __USER_DS in ia32_signal.c.
No impact, because __USER32_DS is defined __USER_DS.
Signed-off-by: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: cleanup
__put_user() can be used for constant size 8, like arch/x86/kernel/signal.c.
Signed-off-by: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: cleanup
Change order of storing to match the sigcontext_ia32.
And add casting to make this code same as arch/x86/kernel/signal_32.c.
Signed-off-by: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: cleanup
No need to use temporary variable.
Also rename the variable same as arch/x86/kernel/signal_32.c.
Signed-off-by: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com>
Reviewed-by: WANG Cong <wangcong@zeuux.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: cleanup
No need to use temporary variable in this case.
Signed-off-by: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: cleanup, no functionality changed
ia32_setup_rt_frame() has a duplicated code block labelled
"Make -mregparm=3 work" for setting up the register parameters
to the user-mode signal handler.
This is harmless but ugly. Remove the redundant assignments.
Signed-off-by: Mikael Pettersson <mikpe@it.uu.se>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
the below 2 functions are called in save_i387_xstate_ia32()
- clear_used_math();
- stts();
Signed-off-by: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
__put_user() looks type of the 2nd parameter, so casting the 1st parameter
is not necessary.
text data bss dec hex filename
6227 0 8 6235 185b ia32_signal.o.new
6227 0 8 6235 185b ia32_signal.o.old
Signed-off-by: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
When setup frame fails, force_sigsegv is called and returns -EFAULT.
There is similar code in ia32_setup_frame(), ia32_setup_rt_frame(),
__setup_frame() and __setup_rt_frame().
Make them identical.
No change in functionality intended.
Signed-off-by: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Use savesegment and loadsegment consistently in ia32 compat code.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
On cpu's supporting xsave/xrstor, fpstate pointer in the sigcontext, will
include the extended state information along with fpstate information. Presence
of extended state information is indicated by the presence
of FP_XSTATE_MAGIC1 at fpstate.sw_reserved.magic1 and FP_XSTATE_MAGIC2
at fpstate + (fpstate.sw_reserved.extended_size - FP_XSTATE_MAGIC2_SIZE).
Extended feature bit mask that is saved in the memory layout is represented
by the fpstate.sw_reserved.xstate_bv
For RT signal frames, UC_FP_XSTATE in the uc_flags also indicate the
presence of extended state information in the sigcontext's fpstate
pointer.
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
move 64bit routines that saves/restores fpstate in/from user stack from
signal_64.c to xsave.c
restore_i387_xstate() now handles the condition when user passes
NULL fpstate.
Other misc changes for prepartion of xsave/xrstor sigcontext support.
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
dynamically allocate fpstate on the stack, instead of static allocation
in the current sigframe layout on the user stack. This will allow the
fpstate structure to grow in the future, which includes extended state
information supporting xsave/xrstor.
signal handlers will be able to access the fpstate pointer from the
sigcontext structure asusual, with no change. For the non RT sigframe's
(which are supported only for 32bit apps), current static fpstate layout
in the sigframe will be unused(so that we don't change the extramask[]
offset in the sigframe and thus prevent breaking app's which modify
extramask[]).
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This was old code that was needed for iBCS and x86-64 never supported that.
Signed-off-by: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Make and use macro FIX_EFLAGS, instead of immediate value 0x40DD5 in
ia32_restore_sigcontext().
Signed-off-by: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com>
Acked-by: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Replace TIF_RESTORE_SIGMASK with TS_RESTORE_SIGMASK and define our own
set_restore_sigmask() function. This saves the costly SMP-safe set_bit
operation, which we do not need for the sigmask flag since TIF_SIGPENDING
always has to be set too.
Signed-off-by: Roland McGrath <roland@redhat.com>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This lifts the set_fs(USER_DS) call for signal handler setup out of the
three places copying the same code into the one place that calls them
all. There is no change in what it does.
Signed-off-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This lifts the code diddling the TF and DF bits for signal handler setup
out of the several places copying the same code into the one place that
calls them all. There is no change in what it does.
I also separated the recently-added DF bit clearing from the TF diddling.
The compiler turns them back into one instruction anyway. The tossing
in of DF to the same line of code with no new comments was a bit more
arcane than seems wise.
Signed-off-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
If the vDSO was not mapped, don't use it as the "restorer" for a signal
handler. Whether we have a pointer in mm->context.vdso depends on what
happened at exec time, so we shouldn't check any global flags now.
Background:
Currently, every 32-bit exec gets the vDSO mapped even if it's disabled
(the process just doesn't get told about it). Because it's in fact
always there, the bug that this patch fixes cannot happen now. With
the second patch, it won't be mapped at all when it's disabled, which is
one of the things that people might really want when they disable it (so
nothing they didn't ask for goes into their address space).
The 32-bit signal handler setup when SA_RESTORER is not used refers to
current->mm->context.vdso without regard to whether the vDSO has been
disabled when the process was exec'd. This patch fixes this not to use
it when it's null, which becomes possible after the second patch. (This
never happens in normal use, because glibc's sigaction call uses
SA_RESTORER unless glibc detected the vDSO.)
Signed-off-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
The Linux kernel currently does not clear the direction flag before
calling a signal handler, whereas the x86/x86-64 ABI requires that.
Linux had this behavior/bug forever, but this becomes a real problem
with gcc version 4.3, which assumes that the direction flag is
correctly cleared at the entry of a function.
This patches changes the setup_frame() functions to clear the
direction before entering the signal handler.
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Acked-by: H. Peter Anvin <hpa@zytor.com>
This revamps the i387 code to be shared across 32-bit, 64-bit,
and 32-on-64. It does so by consolidating the code in one place
based on the user_regset accessor interfaces. This switches
32-bit to using the i387_64.h header and 64-bit to using the
i387.c that was previously i387_32.c, but that's what took the
least cleanup in each file. Here i387.h is stubbed to always
include i387_64.h rather than renaming the file, to keep this
diff smaller and easier to read.
Signed-off-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
There's no need for the *_MASK flags (TF_MASK, IF_MASK, etc), found in
processor.h (both _32 and _64). They have a one-to-one mapping with the
EFLAGS value. This patch removes the definitions, and use the already
existent X86_EFLAGS_ version when applicable.
[ roland@redhat.com: KVM build fixes. ]
Signed-off-by: Glauber de Oliveira Costa <gcosta@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Switch struct sigcontext (defined in <asm/sigcontext*.h>) to using
register names withut e- or r-prefixes for both 32- and 64-bit x86.
This is intended as a preliminary step in unifying this code between
architectures.
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
We have a lot of code which differs only by the naming of specific
members of structures that contain registers. In order to enable
additional unifications, this patch drops the e- or r- size prefix
from the register names in struct pt_regs, and drops the x- prefixes
for segment registers on the 32-bit side.
This patch also performs the equivalent renames in some additional
places that might be candidates for unification in the future.
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
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>
