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>
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>
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>
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>
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>
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>
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>
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>
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>
* 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
...
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>
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>
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>
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>
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>
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>
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>
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>
