Commit Graph

72 Commits

Author SHA1 Message Date
Russell King e94c805f0c Merge branch 'for-arm' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal.git into for-linus
Conflicts:
	arch/arm/kernel/ptrace.c
2012-05-29 22:13:55 +01:00
Al Viro 21c1176a72 arm: if we get into work_pending while returning to kernel mode, just go away
checking in do_signal() is pointless - if we get there with !user_mode(regs)
(and we might), we'll end up looping indefinitely.  Check in work_pending
and break out of the loop if so.

Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-05-21 14:38:24 -04:00
Al Viro 84849b3ed8 arm: trim _TIF_WORK_MASK, get rid of useless test and branch...
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-05-21 14:36:32 -04:00
Russell King 357c9c1f07 ARM: Remove support for ARMv3 ARM610 and ARM710 CPUs
This patch removes support for ARMv3 CPUs, which haven't worked properly
for quite some time (see the FIXME comment in arch/arm/mm/fault.c).  The
only V3 parts left is the cache model for ARMv3, which is needed for some
odd reason by ARM740T CPUs, and being able to build with -march=armv3,
which is required for the RiscPC platform due to its bus structure.

Acked-by: Will Deacon <will.deacon@arm.com>
Acked-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-05-05 05:50:50 +01:00
Rob Herring 13a5045d4e ARM: make arch_ret_to_user macro optional
Only 3 platforms need arch_ret_to_user macro, so add ARCH_HAS_RET_TO_USER
kconfig option and make iop13xx, iop32x and iop33x select it.

Signed-off-by: Rob Herring <rob.herring@calxeda.com>
Acked-by: Nicolas Pitre <nico@linaro.org>
2012-02-21 17:04:10 -06:00
Rabin Vincent d68133b5a8 ARM: 7299/1: ftrace: clear zero bit in reported IPs for Thumb-2
The dynamic ftrace ops startup test currently fails on Thumb-2 kernels:

 Testing tracer function: PASSED
 Testing dynamic ftrace: PASSED
 Testing dynamic ftrace ops #1: (0 0 0 0 0) FAILED!

This is because while the addresses in the mcount records do not have
the zero bit set, the IP reported by the mcount call does have it set
(because it is copied from the LR).  This mismatch causes the ops
filtering in ftrace_ops_list_func() to not call the relevant tracers.

Fix this by clearing the zero bit before adjusting the LR for the mcount
instruction size.  Also, combine the mov+sub into a single sub
instruction.

Acked-by: Dave Martin <dave.martin@linaro.org>
Signed-off-by: Rabin Vincent <rabin@rab.in>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-01-25 09:24:37 +00:00
Nathaniel Husted 29ef73b7a8 Kernel: Audit Support For The ARM Platform
This patch provides functionality to audit system call events on the
ARM platform. The implementation was based off the structure of the
MIPS platform and information in this
(http://lists.fedoraproject.org/pipermail/arm/2009-October/000382.html)
mailing list thread. The required audit_syscall_exit and
audit_syscall_entry checks were added to ptrace using the standard
registers for system call values (r0 through r3). A thread information
flag was added for auditing (TIF_SYSCALL_AUDIT) and a meta-flag was
added (_TIF_SYSCALL_WORK) to simplify modifications to the syscall
entry/exit. Now, if either the TRACE flag is set or the AUDIT flag is
set, the syscall_trace function will be executed. The prober changes
were made to Kconfig to allow CONFIG_AUDITSYSCALL to be enabled.

Due to platform availability limitations, this patch was only tested
on the Android platform running the modified "android-goldfish-2.6.29"
kernel. A test compile was performed using Code Sourcery's
cross-compilation toolset and the current linux-3.0 stable kernel. The
changes compile without error. I'm hoping, due to the simple modifications,
the patch is "obviously correct".

Signed-off-by: Nathaniel Husted <nhusted@gmail.com>
Signed-off-by: Eric Paris <eparis@redhat.com>
2012-01-17 16:17:01 -05:00
Ming Lei 9fc2552a68 ARM: 6952/1: fix lockdep warning of "unannotated irqs-off"
This patch fixes the lockdep warning of "unannotated irqs-off"[1].

After entering __irq_usr, arm core will disable interrupt automatically,
but __irq_usr does not annotate the irq disable, so lockdep may complain
the warning if it has chance to check this in irq handler.

This patch adds trace_hardirqs_off in __irq_usr before entering irq_handler
to handle the irq, also calls ret_to_user_from_irq to avoid calling
disable_irq again.

This is also a fix for irq off tracer.

[1], lockdep warning log of "unannotated irqs-off"

[   13.804687] ------------[ cut here ]------------
[   13.809570] WARNING: at kernel/lockdep.c:3335 check_flags+0x78/0x1d0()
[   13.816467] Modules linked in:
[   13.819732] Backtrace:
[   13.822357] [<c01cb42c>] (dump_backtrace+0x0/0x100) from [<c06abb14>] (dump_stack+0x20/0x24)
[   13.831268]  r6:c07d8c2c r5:00000d07 r4:00000000 r3:00000000
[   13.837280] [<c06abaf4>] (dump_stack+0x0/0x24) from [<c01ffc04>] (warn_slowpath_common+0x5c/0x74)
[   13.846649] [<c01ffba8>] (warn_slowpath_common+0x0/0x74) from [<c01ffc48>] (warn_slowpath_null+0x2c/0x34)
[   13.856781]  r8:00000000 r7:00000000 r6:c18b8194 r5:60000093 r4:ef182000
[   13.863708] r3:00000009
[   13.866485] [<c01ffc1c>] (warn_slowpath_null+0x0/0x34) from [<c0237d84>] (check_flags+0x78/0x1d0)
[   13.875823] [<c0237d0c>] (check_flags+0x0/0x1d0) from [<c023afc8>] (lock_acquire+0x4c/0x150)
[   13.884704] [<c023af7c>] (lock_acquire+0x0/0x150) from [<c06af638>] (_raw_spin_lock+0x4c/0x84)
[   13.893798] [<c06af5ec>] (_raw_spin_lock+0x0/0x84) from [<c01f9a44>] (sched_ttwu_pending+0x58/0x8c)
[   13.903320]  r6:ef92d040 r5:00000003 r4:c18b8180
[   13.908233] [<c01f99ec>] (sched_ttwu_pending+0x0/0x8c) from [<c01f9a90>] (scheduler_ipi+0x18/0x1c)
[   13.917663]  r6:ef183fb0 r5:00000003 r4:00000000 r3:00000001
[   13.923645] [<c01f9a78>] (scheduler_ipi+0x0/0x1c) from [<c01bc458>] (do_IPI+0x9c/0xfc)
[   13.932006] [<c01bc3bc>] (do_IPI+0x0/0xfc) from [<c06b0888>] (__irq_usr+0x48/0xe0)
[   13.939971] Exception stack(0xef183fb0 to 0xef183ff8)
[   13.945281] 3fa0:                                     ffffffc3 0001500c 00000001 0001500c
[   13.953948] 3fc0: 00000050 400b45f0 400d9000 00000000 00000001 400d9600 6474e552 bea05b3c
[   13.962585] 3fe0: 400d96c0 bea059c0 400b6574 400b65d8 20000010 ffffffff
[   13.969573]  r6:00000403 r5:fa240100 r4:ffffffff r3:20000010
[   13.975585] ---[ end trace efc4896ab0fb62cb ]---
[   13.980468] possible reason: unannotated irqs-off.
[   13.985534] irq event stamp: 1610
[   13.989044] hardirqs last  enabled at (1610): [<c01c703c>] no_work_pending+0x8/0x2c
[   13.997131] hardirqs last disabled at (1609): [<c01c7024>] ret_slow_syscall+0xc/0x1c
[   14.005371] softirqs last  enabled at (0): [<c01fe5e4>] copy_process+0x2cc/0xa24
[   14.013183] softirqs last disabled at (0): [<  (null)>]   (null)

Signed-off-by: Ming Lei <ming.lei@canonical.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-06-06 10:56:22 +01:00
Russell King 58daf18cdc Merge branch 'clksrc' into devel
Conflicts:
	arch/arm/mach-vexpress/v2m.c
	arch/arm/plat-omap/counter_32k.c
	arch/arm/plat-versatile/Makefile
2011-01-05 18:09:03 +00:00
Todd Android Poynor d13e5edd72 ARM: 6540/1: Stop irqsoff trace on return to user
If the irqsoff tracer is in use, stop tracing the interrupt disable
interval when returning to userspace.  Tracing userspace execution time
as interrupts disabled time is not helpful for kernel performance
analysis purposes.  Only do so if the irqsoff tracer is enabled, to
avoid overhead for lockdep, which doesn't care.

Signed-off-by: Todd Poynor <toddpoynor@google.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-12-24 09:37:59 +00:00
Rabin Vincent dd686eb139 ARM: ftrace: graph tracer + dynamic ftrace
Support the graph tracer + dynamic ftrace combination on ARM.

Signed-off-by: Rabin Vincent <rabin@rab.in>
2010-11-19 21:43:27 +05:30
Tim Bird 376cfa8730 ARM: ftrace: function graph tracer support
Cc: Tim Bird <tim.bird@am.sony.com>
[rabin@rab.in: rebase on top of latest code,
	       keep code in ftrace.c instead of separate file,
	       check for ftrace_graph_entry also]
Signed-off-by: Rabin Vincent <rabin@rab.in>
2010-11-19 21:43:27 +05:30
Rabin Vincent d3b9dc9dd2 ARM: ftrace: use gas macros to avoid code duplication
Use assembler macros to avoid copy/pasting code between the
implementations of the two variants of the mcount call.

Signed-off-by: Rabin Vincent <rabin@rab.in>
2010-11-19 21:43:26 +05:30
Russell King 809b4e00ba Merge branch 'devel-stable' into devel 2010-10-19 22:06:36 +01:00
Russell King 23beab76b4 Merge branches 'at91', 'dcache', 'ftrace', 'hwbpt', 'misc', 'mmci', 's3c', 'st-ux' and 'unwind' into devel 2010-10-18 22:34:25 +01:00
Nicolas Pitre 70c70d9780 ARM: SECCOMP support
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2010-10-01 22:32:18 -04:00
Linus Torvalds 6e029fe373 Merge master.kernel.org:/home/rmk/linux-2.6-arm
* master.kernel.org:/home/rmk/linux-2.6-arm: (28 commits)
  ARM: 6411/1: vexpress: set RAM latencies to 1 cycle for PL310 on ct-ca9x4 tile
  ARM: 6409/1: davinci: map sram using MT_MEMORY_NONCACHED instead of MT_DEVICE
  ARM: 6408/1: omap: Map only available sram memory
  ARM: 6407/1: mmu: Setup MT_MEMORY and MT_MEMORY_NONCACHED L1 entries
  ARM: pxa: remove pr_<level> uses of KERN_<level>
  ARM: pxa168fb: clear enable bit when not active
  ARM: pxa: fix cpu_is_pxa*() not expanding to zero when not configured
  ARM: pxa168: fix corrected reset vector
  ARM: pxa: Use PIO for PI2C communication on Palm27x
  ARM: pxa: Fix Vpac270 gpio_power for MMC
  ARM: 6401/1: plug a race in the alignment trap handler
  ARM: 6406/1: at91sam9g45: fix i2c bus speed
  leds: leds-ns2: fix locking
  ARM: dove: fix __io() definition to use bus based offset
  dmaengine: fix interrupt clearing for mv_xor
  ARM: kirkwood: Unbreak PCIe I/O port
  ARM: Fix build error when using KCONFIG_CONFIG
  ARM: 6383/1: Implement phys_mem_access_prot() to avoid attributes aliasing
  ARM: 6400/1: at91: fix arch_gettimeoffset fallout
  ARM: 6398/1: add proc info for ARM11MPCore/Cortex-A9 from ARM
  ...
2010-09-27 12:32:36 -07:00
Al Viro 653d48b221 arm: fix really nasty sigreturn bug
If a signal hits us outside of a syscall and another gets delivered
when we are in sigreturn (e.g. because it had been in sa_mask for
the first one and got sent to us while we'd been in the first handler),
we have a chance of returning from the second handler to location one
insn prior to where we ought to return.  If r0 happens to contain -513
(-ERESTARTNOINTR), sigreturn will get confused into doing restart
syscall song and dance.

Incredible joy to debug, since it manifests as random, infrequent and
very hard to reproduce double execution of instructions in userland
code...

The fix is simple - mark it "don't bother with restarts" in wrapper,
i.e. set r8 to 0 in sys_sigreturn and sys_rt_sigreturn wrappers,
suppressing the syscall restart handling on return from these guys.
They can't legitimately return a restart-worthy error anyway.

Testcase:
	#include <unistd.h>
	#include <signal.h>
	#include <stdlib.h>
	#include <sys/time.h>
	#include <errno.h>

	void f(int n)
	{
		__asm__ __volatile__(
			"ldr r0, [%0]\n"
			"b 1f\n"
			"b 2f\n"
			"1:b .\n"
			"2:\n" : : "r"(&n));
	}

	void handler1(int sig) { }
	void handler2(int sig) { raise(1); }
	void handler3(int sig) { exit(0); }

	main()
	{
		struct sigaction s = {.sa_handler = handler2};
		struct itimerval t1 = { .it_value = {1} };
		struct itimerval t2 = { .it_value = {2} };

		signal(1, handler1);

		sigemptyset(&s.sa_mask);
		sigaddset(&s.sa_mask, 1);
		sigaction(SIGALRM, &s, NULL);

		signal(SIGVTALRM, handler3);

		setitimer(ITIMER_REAL, &t1, NULL);
		setitimer(ITIMER_VIRTUAL, &t2, NULL);

		f(-513); /* -ERESTARTNOINTR */

		write(1, "buggered\n", 9);
		return 1;
	}

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-09-17 10:22:18 -07:00
Russell King b2b163bb82 ARM: prevent multiple syscall restarts
Al Viro reports that calling "sys_sigsuspend(-ERESTARTNOHAND, 0, 0)"
with two signals coming and being handled in kernel space results
in the syscall restart being done twice.

Avoid this by clearing the 'why' flag when we call the signal handling
code to prevent further syscall restarts after the first.

Acked-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-09-17 14:56:16 +01:00
Rabin Vincent 3b6c223b1b ARM: 6318/1: ftrace: fix and update dynamic ftrace
This adds mcount recording and updates dynamic ftrace for ARM to work
with the new ftrace dyamic tracing implementation.  It also adds support
for the mcount format used by newer ARM compilers.

With dynamic tracing, mcount() is implemented as a nop.  Callsites are
patched on startup with nops, and dynamically patched to call to the
ftrace_caller() routine as needed.

Acked-by: Steven Rostedt <rostedt@goodmis.org> [recordmcount.pl change]
Signed-off-by: Rabin Vincent <rabin@rab.in>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-09-02 15:27:40 +01:00
Rabin Vincent a3ba87a614 ARM: 6316/1: ftrace: add Thumb-2 support
Fix the mcount routines to build and run on a kernel built with the
Thumb-2 instruction set by correcting the following errors using the
fixes suggested by Catalin Marinas:

 - Problem: The following assembler errors appear at the "adr r0,
   ftrace_stub" instruction:

   entry-common.S: Assembler messages:
   entry-common.S:179: Error: invalid immediate for address calculation (value = 0x00000004)

   Fix: The errors don't occur with a non-global symbol, so use one.

 - Problem: The "mov lr, pc" does not set the lsb when storing the pc in
   lr.  The called function returns with "bx lr", and the mode changes
   to ARM.

   Fix: Add a label on the return address and use "adr lr, BSYM(label)".

We don't modify the old mcount because it won't be built when using
Thumb-2.

Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Rabin Vincent <rabin@rab.in>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-09-02 15:26:12 +01:00
Rabin Vincent 72fa62fa5d ARM: 6315/1: ftrace: add ENDPROC annotations
When building as Thumb-2, the ".type foo, %function" annotation in
ENDPROC seems to be required in order for the assembly routines to be
recognized as Thumb-2 code.  If the ENDPROC annotations are not present,
calls to these routines are generated as BLX instead of BL.

Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Rabin Vincent <rabin@rab.in>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-09-02 15:25:27 +01:00
Rabin Vincent 09bfafac3e ARM: 6314/1: ftrace: allow build without frame pointers on ARM
With a new enough GCC, ARM function tracing can be supported without the
need for frame pointers.  This is essential for Thumb-2 support, since
frame pointers aren't available then.

Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Rabin Vincent <rabin@rab.in>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-09-02 15:24:53 +01:00
Rabin Vincent 686ff22812 ARM: 6288/1: ftrace: document mcount formats
Add a comment describing the mcount variants and how the callsites look
like.

Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Rabin Vincent <rabin@rab.in>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-08-10 22:10:52 +01:00
Rabin Vincent 28e192d6e5 ARM: 6287/1: ftrace: clean up mcount assembly indentation
The mcount implementation currently uses a different indentation style
from the rest of the file (and the rest of the ARM assembly in the
kernel).  Clean it up.

Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Rabin Vincent <rabin@rab.in>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-08-10 22:10:52 +01:00
Al Viro f8b7256096 Unify sys_mmap*
New helper - sys_mmap_pgoff(); switch syscalls to using it.

Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-12-11 06:44:29 -05:00
Kirill A. Shutemov 4fb2847437 ARM: 5727/1: Pass IFSR register to do_PrefetchAbort()
Instruction fault status register, IFSR, was introduced on ARMv6 to
provide status information about the last insturction fault. It
needed for proper prefetch abort handling.

Now we have three prefetch abort model:

  * legacy - for CPUs before ARMv6. They doesn't provide neither
    IFSR nor IFAR. We simulate IFSR with section translation fault
    status for them to generalize code;
  * ARMv6 - provides IFSR, but not IFAR;
  * ARMv7 - provides both IFSR and IFAR.

Signed-off-by: Kirill A. Shutemov <kirill@shutemov.name>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-10-02 22:34:32 +01:00
Dmitry Artamonow 6176d39471 ARM: 5734/1: arm: fix compilation of entry-common.S for older CPUs
Commit 181f817eaa introduced some new code to entry-common.S
Sadly, this new code uses 'bx' instruction which is available only on
ARMv5 and higher CPUs. This causes following compilation errors when
building kernel for StrongARM (ARMv4):

arch/arm/kernel/entry-common.S: Assembler messages:
arch/arm/kernel/entry-common.S:129: Error: selected processor does not
 support `bx ip'
arch/arm/kernel/entry-common.S:138: Error: selected processor does not
 support `bx ip'

Fix these errors by using 'mov pc' instead of 'bx'.

Signed-off-by: Dmitry Artamonow <mad_soft@inbox.ru>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-10-01 16:26:16 +01:00
Linus Torvalds 2ca7d674d7 Merge branch 'devel' of master.kernel.org:/home/rmk/linux-2.6-arm
* 'devel' of master.kernel.org:/home/rmk/linux-2.6-arm: (257 commits)
  [ARM] Update mach-types
  ARM: 5636/1: Move vendor enum to AMBA include
  ARM: Fix pfn_valid() for sparse memory
  [ARM] orion5x: Add LaCie NAS 2Big Network support
  [ARM] pxa/sharpsl_pm: zaurus c3000 aka spitz: fix resume
  ARM: 5686/1: at91: Correct AC97 reset line in at91sam9263ek board
  ARM: 5640/1: This patch modifies the support of AC97 on the at91sam9263 ek board
  ARM: 5689/1: Update default config of HP Jornada 700-series machines
  ARM: 5691/1: fix cache aliasing issues between kmap() and kmap_atomic() with highmem
  ARM: 5688/1: ks8695_serial: disable_irq() lockup
  ARM: 5687/1: fix an oops with highmem
  ARM: 5684/1: Add nuc960 platform to w90x900
  ARM: 5683/1: Add nuc950 platform to w90x900
  ARM: 5682/1: Add cpu.c and dev.c and modify some files of w90p910 platform
  ARM: 5626/1: add suspend/resume functions to amba-pl011 serial driver
  ARM: 5625/1: fix hard coded 4K resource size in amba bus detection
  MMC: MMCI: convert realview MMC to use gpiolib
  ARM: 5685/1: Make MMCI driver compile without gpiolib
  ARM: implement highpte
  ARM: Show FIQ in /proc/interrupts on CONFIG_FIQ
  ...

Fix up trivial conflict in arch/arm/kernel/signal.c.

It was due to the TIF_NOTIFY_RESUME addition in commit d0420c83f ("KEYS:
Extend TIF_NOTIFY_RESUME to (almost) all architectures") and follow-ups.
2009-09-14 17:48:14 -07:00
Russell King 87d721ad7a Merge branch 'master' into devel 2009-09-12 12:04:37 +01:00
Russell King ddd559b13f Merge branch 'devel-stable' into devel
Conflicts:
	MAINTAINERS
	arch/arm/mm/fault.c
2009-09-12 12:02:26 +01:00
David Howells d0420c83f3 KEYS: Extend TIF_NOTIFY_RESUME to (almost) all architectures [try #6]
Implement TIF_NOTIFY_RESUME for most of those architectures in which isn't yet
available, and, whilst we're at it, have it call the appropriate tracehook.

After this patch, blackfin, m68k* and xtensa still lack support and need
alteration of assembly code to make it work.

Resume notification can then be used (by a later patch) to install a new
session keyring on the parent of a process.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>

cc: linux-arch@vger.kernel.org
Signed-off-by: James Morris <jmorris@namei.org>
2009-09-02 21:29:19 +10:00
Russell King 9b2616c2e8 Merge branch 'for-rmk-2.6.32' of git://git.pengutronix.de/git/ukl/linux-2.6 into devel-stable 2009-08-15 16:51:48 +01:00
Mikael Pettersson 369842658a ARM: 5677/1: ARM support for TIF_RESTORE_SIGMASK/pselect6/ppoll/epoll_pwait
This patch adds support for TIF_RESTORE_SIGMASK to ARM's
signal handling, which allows to hook up the pselect6, ppoll,
and epoll_pwait syscalls on ARM.

Tested here with eabi userspace and a test program with a
deliberate race between a child's exit and the parent's
sigprocmask/select sequence. Using sys_pselect6() instead
of sigprocmask/select reliably prevents the race.

The other arch's support for TIF_RESTORE_SIGMASK has evolved
over time:

In 2.6.16:
- add TIF_RESTORE_SIGMASK which parallels TIF_SIGPENDING
- test both when checking for pending signal [changed later]
- reimplement sys_sigsuspend() to use current->saved_sigmask,
  TIF_RESTORE_SIGMASK [changed later], and -ERESTARTNOHAND;
  ditto for sys_rt_sigsuspend(), but drop private code and
  use common code via __ARCH_WANT_SYS_RT_SIGSUSPEND;
- there are now no "extra" calls to do_signal() so its oldset
  parameter is always &current->blocked so need not be passed,
  also its return value is changed to void
- change handle_signal() to return 0/-errno
- change do_signal() to honor TIF_RESTORE_SIGMASK:
  + get oldset from current->saved_sigmask if TIF_RESTORE_SIGMASK
    is set
  + if handle_signal() was successful then clear TIF_RESTORE_SIGMASK
  + if no signal was delivered and TIF_RESTORE_SIGMASK is set then
    clear it and restore the sigmask
- hook up sys_pselect6() and sys_ppoll()

In 2.6.19:
- hook up sys_epoll_pwait()

In 2.6.26:
- allow archs to override how TIF_RESTORE_SIGMASK is implemented;
  default set_restore_sigmask() sets both TIF_RESTORE_SIGMASK and
  TIF_SIGPENDING; archs need now just test TIF_SIGPENDING again
  when checking for pending signal work; some archs now implement
  TIF_RESTORE_SIGMASK as a secondary/non-atomic thread flag bit
- call set_restore_sigmask() in sys_sigsuspend() instead of setting
  TIF_RESTORE_SIGMASK

In 2.6.29-rc:
- kill sys_pselect7() which no arch wanted

So for 2.6.31-rc6/ARM this patch does the following:
- Add TIF_RESTORE_SIGMASK. Use the generic set_restore_sigmask()
  which sets both TIF_SIGPENDING and TIF_RESTORE_SIGMASK, so
  TIF_RESTORE_SIGMASK need not claim one of the scarce low thread
  flags, and existing TIF_SIGPENDING and _TIF_WORK_MASK tests need
  not be extended for TIF_RESTORE_SIGMASK.
- sys_sigsuspend() is reimplemented to use current->saved_sigmask
  and set_restore_sigmask(), making it identical to most other archs
- The private code for sys_rt_sigsuspend() is removed, instead
  generic code supplies it via __ARCH_WANT_SYS_RT_SIGSUSPEND.
- sys_sigsuspend() and sys_rt_sigsuspend() no longer need a pt_regs
  parameter, so their assembly code wrappers are removed.
- handle_signal() is changed to return 0 on success or -errno.
- The oldset parameter to do_signal() is now redundant and removed,
  and the return value is now also redundant and changed to void.
- do_signal() is changed to honor TIF_RESTORE_SIGMASK:
  + get oldset from current->saved_sigmask if TIF_RESTORE_SIGMASK
    is set
  + if handle_signal() was successful then clear TIF_RESTORE_SIGMASK
  + if no signal was delivered and TIF_RESTORE_SIGMASK is set then
    clear it and restore the sigmask
- Hook up sys_pselect6, sys_ppoll, and sys_epoll_pwait.

Signed-off-by: Mikael Pettersson <mikpe@it.uu.se>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-08-15 15:10:31 +01:00
Uwe Kleine-König 181f817eaa [ARM] support tracing when using newer compilers
Since gcc 4.4 the name and calling convention for function profiling
on ARM changed.  With this patch both types are supported.

See http://sourceware.org/ml/libc-ports/2008-04/msg00009.html for some
details.

Lightly-Tested-by: Anand Gadiyar <gadiyar@ti.com>
Tested-by: Kevin Hilman <khilman@deeprootsystems.com>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
2009-08-13 20:34:36 +02:00
Uwe Kleine-König 3ef7143d22 ARM: 5627/1: Fix restoring of lr at the end of mcount
After ftrace_trace_function is called r1 is probably clobbered so don't
try to use its value for restoring.

This was introduced in v2.6.29~38^2~7

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-07-30 10:44:16 +01:00
Catalin Marinas b86040a59f Thumb-2: Implementation of the unified start-up and exceptions code
This patch implements the ARM/Thumb-2 unified kernel start-up and
exception handling code.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2009-07-24 12:32:54 +01:00
Catalin Marinas 26584853a4 Add core support for ARMv6/v7 big-endian
Starting with ARMv6, the CPUs support the BE-8 variant of big-endian
(byte-invariant). This patch adds the core support:

- setting of the BE-8 mode via the CPSR.E register for both kernel and
  user threads
- big-endian page table walking
- REV used to rotate instructions read from memory during fault
  processing as they are still little-endian format
- Kconfig and Makefile support for BE-8. The --be8 option must be passed
  to the final linking stage to convert the instructions to
  little-endian

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2009-05-30 14:00:18 +01:00
Russell King 7d83f8fca5 Merge branch 'master' of git://git.marvell.com/orion into devel
Conflicts:

	arch/arm/mach-mx1/devices.c
2009-03-19 23:10:40 +00:00
Uwe Kleine-König d4cc510c61 [ARM] 5418/1: restore lr before leaving mcount
gcc seems to expect that lr isn't clobbered by mcount, because for a
function starting with:

	static int func(void)
	{
		void *ra = __builtin_return_address(0);

		printk(KERN_EMERG "__builtin_return_address(0) = %pS\n", ra)

		...

the following assembler is generated by gcc 4.3.2:

	   0:   e1a0c00d        mov     ip, sp
	   4:   e92dd810        push    {r4, fp, ip, lr, pc}
	   8:   e24cb004        sub     fp, ip, #4      ; 0x4
	   c:   ebfffffe        bl      0 <mcount>
	  10:   e59f0034        ldr     r0, [pc, #52]
	  14:   e1a0100e        mov     r1, lr
	  18:   ebfffffe        bl      0 <printk>

Without this patch obviously __builtin_return_address(0) yields
func+0x10 instead of the return address of the caller.

Note this patch fixes a similar issue for the routines used with dynamic
ftrace even though this isn't currently selectable for ARM.

Cc: Abhishek Sagar <sagar.abhishek@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-03-05 13:47:15 +00:00
Catalin Marinas c4c5716e16 [ARM] 5385/2: unwind: Add unwinding information to exception entry points
This is needed to allow or stop the unwinding at certain points in the
kernel like exception entries.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-02-19 11:27:35 +00:00
Uwe Kleine-König b3c960b277 annotate that [fp, #-4] is the saved lr
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
2009-01-31 01:21:56 +01:00
Steven Rostedt 606576ce81 ftrace: rename FTRACE to FUNCTION_TRACER
Due to confusion between the ftrace infrastructure and the gcc profiling
tracer "ftrace", this patch renames the config options from FTRACE to
FUNCTION_TRACER.  The other two names that are offspring from FTRACE
DYNAMIC_FTRACE and FTRACE_MCOUNT_RECORD will stay the same.

This patch was generated mostly by script, and partially by hand.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-10-20 18:27:03 +02:00
Catalin Marinas 93ed397011 [ARM] 5227/1: Add the ENDPROC declarations to the .S files
This declaration specifies the "function" type and size for various
assembly functions, mainly needed for generating the correct branch
instructions in Thumb-2.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2008-09-01 12:06:34 +01:00
Russell King a09e64fbc0 [ARM] Move include/asm-arm/arch-* to arch/arm/*/include/mach
This just leaves include/asm-arm/plat-* to deal with.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2008-08-07 09:55:48 +01:00
Abhishek Sagar 395a59d0f8 ftrace: store mcount address in rec->ip
Record the address of the mcount call-site. Currently all archs except sparc64
record the address of the instruction following the mcount call-site. Some
general cleanups are entailed. Storing mcount addresses in rec->ip enables
looking them up in the kprobe hash table later on to check if they're kprobe'd.

Signed-off-by: Abhishek Sagar <sagar.abhishek@gmail.com>
Cc: davem@davemloft.net
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-06-23 22:10:56 +02:00
Abhishek Sagar 014c257cce ftrace: core support for ARM
Core ftrace support for the ARM architecture, which includes support
for dynamic function tracing.

Signed-off-by: Abhishek Sagar <sagar.abhishek@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-06-02 11:32:20 +02:00
Paul Brook 48d7927bdf Add a prefetch abort handler
This patch adds a prefetch abort handler similar to the data abort one
and renames the latter for consistency. Initial implementation by Paul
Brook with some renaming by Catalin Marinas.

Signed-off-by: Paul Brook <paul@codesourcery.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2008-04-18 22:43:07 +01:00
George G. Davis 7b544c99e0 [ARM] 4687/1: Trivial arch/arm/kernel/entry-common.S comment fix
Make the comment match the code

Signed-off-by: George G. Davis <gdavis@mvista.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2008-01-26 14:50:04 +00:00
Stephane Eranian a583f1b542 remove unused TIF_NOTIFY_RESUME flag
Remove unused TIF_NOTIFY_RESUME flag for all processor architectures.  The
flag was not used excecpt on IA-64 where the patch replaces it with
TIF_PERFMON_WORK.

Signed-off-by: stephane eranian <eranian@hpl.hp.com>
Cc: <linux-arch@vger.kernel.org>
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>
2007-07-31 15:39:38 -07:00