* 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>
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>
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>
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>
Commit 181f817eaaca4c1f 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>
* '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.