This fixes a kernel panic on boot due to do_signal not being compatible
with it's callers.
- do_signal now returns void, and does not have the previous signal set
as a parameter.
- Remove sys_rt_sigsuspend, we can use the common one instead.
- Change sys_sigsuspend to be more like x86, don't call do_signal here.
- handle_signal, setup_frame and setup_rt_frame now return -EFAULT
if we've delivered a segfault, which is used by callers to perform
necessary cleanup.
- Break long lines, correct whitespace and formatting errors.
Signed-off-by: Jesper Nilsson <jesper.nilsson@axis.com>
Cc: Mikael Starvik <mikael.starvik@axis.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Sometimes cpu_idle_wait gets stuck because it might miss CPUS that are
already in idle, have no tasks waiting to run and have no interrupts going
to them. This is common on bootup when switching cpu idle governors.
This patch gives those CPUS that don't check in an IPI kick.
Background:
-----------
I notice this while developing the mcount patches, that every once in a
while the system would hang. Looking deeper, the hang was always at boot
up when registering init_menu of the cpu_idle menu governor. Talking
with Thomas Gliexner, we discovered that one of the CPUS had no timer
events scheduled for it and it was in idle (running with NO_HZ). So the
CPU would not set the cpu_idle_state bit.
Hitting sysrq-t a few times would eventually route the interrupt to the
stuck CPU and the system would continue.
Note, I would have used the PDA isidle but that is set after the
cpu_idle_state bit is cleared, and would leave a window open where we
may miss being kicked.
hmm, looking closer at this, we still have a small race window between
clearing the cpu_idle_state and disabling interrupts (hence the RFC).
CPU0: CPU 1:
--------- ---------
cpu_idle_wait(): cpu_idle():
| __cpu_cpu_var(is_idle) = 1;
| if (__get_cpu_var(cpu_idle_state)) /* == 0 */
per_cpu(cpu_idle_state, 1) = 1; |
if (per_cpu(is_idle, 1)) /* == 1 */ |
smp_call_function(1) |
| receives ipi and runs do_nothing.
wait on map == empty idle();
/* waits forever */
So really we need interrupts off for most of this then. One might think
that we could simply clear the cpu_idle_state from do_nothing, but I'm
assuming that cpu_idle governors can be removed, and this might cause a
race that a governor might be used after the module was removed.
Venki said:
I think your RFC patch is the right solution here. As I see it, there is
no race with your RFC patch. As long as you call a dummy smp_call_function
on all CPUs, we should be OK. We can get rid of cpu_idle_state and the
current wait forever logic altogether with dummy smp_call_function. And so
there wont be any wait forever scenario.
The whole point of cpu_idle_wait() is to make all CPUs come out of idle
loop atleast once. The caller will use cpu_idle_wait something like this.
// Want to change idle handler
- Switch global idle handler to always present default_idle
- call cpu_idle_wait so that all cpus come out of idle for an instant
and stop using old idle pointer and start using default idle
- Change the idle handler to a new handler
- optional cpu_idle_wait if you want all cpus to start using the new
handler immediately.
Maybe the below 1s patch is safe bet for .24. But for .25, I would say we
just replace all complicated logic by simple dummy smp_call_function and
remove cpu_idle_state altogether.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Cc: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andi Kleen <ak@suse.de>
Cc: Len Brown <lenb@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc:
[POWERPC] Fix CPU hotplug when using the SLB shadow buffer
[POWERPC] efika: add phy-handle property for fec_mpc52xx
* 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6:
pnpacpi: print resource shortage message only once
PM: ACPI and APM must not be enabled at the same time
ACPI: apply quirk_ich6_lpc_acpi to more ICH8 and ICH9
ACPICA: fix acpi_serialize hang regression
ACPI : Not register gsi for PCI IDE controller in legacy mode
ACPI: Reintroduce run time configurable max_cstate for !CPU_IDLE case
ACPI: Make sysfs interface in ACPI power optional.
ACPI: EC: Enable boot EC before bus_scan
increase PNP_MAX_PORT to 40 from 24
ACPI and APM used "pm_active" to guarantee that
they would not be simultaneously active.
But pm_active was recently moved under CONFIG_PM_LEGACY,
so that without CONFIG_PM_LEGACY, pm_active became a NOP --
allowing ACPI and APM to both be simultaneously enabled.
This caused unpredictable results, including boot hangs.
Further, the code under CONFIG_PM_LEGACY is scheduled
for removal.
So replace pm_active with pm_flags.
pm_flags depends only on CONFIG_PM,
which is present for both CONFIG_APM and CONFIG_ACPI.
http://bugzilla.kernel.org/show_bug.cgi?id=9194
Signed-off-by: Len Brown <len.brown@intel.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
I noticed that the commit f197465384
(MIPS Tech: Get rid of volatile in core code) broke the software
reset functionality for MIPS Malta boards in big-endian mode.
According to the MIPS Malta board user's manual, writing the magic
32-bit GORESET value into the SOFTRES register initiates board soft
reset. My experimentation has shown that the endianness of the GORESET
integer should thereby be the same as the endianness, which has been
set for the CPU itself. The writew() function used to write the magic
value in the code introduced by the commit mentioned above, however,
swaps bytes for big-endian kernels and transfers 16 bits instead of 32.
The patch below replaces the writew() function by the __raw_writel()
routine, which leaves the byte order intact and transfers the whole
MIPS machine word. Trivial code cleanup (replacing spaces by a tab
and cutting oversized lines to make checkpatch.pl happy) is also
included.
The patch was tested using a Malta evaluation board running in both
BE and LE modes. For both modes, software reset was fully functional
after the change.
P.S. I suspect that the same commit broke the "standby" functionality
for MIPS Atlas boards. However, I did not touch the Atlas code as I
don't have such board at my disposal and also because the linux-mips.org
Web site claims that Atlas support is scheduled for removal.
Signed-off-by: Dmitri Vorobiev <dmitri.vorobiev@gmail.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
This patch converts PNX8XXX system timer to clocksource restoring PNX8550
support back to live.
Signed-off-by: Vitaly Wool <vitalywool@gmail.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Before we register the SLB shadow buffer, we need to invalidate the
entries in the buffer, otherwise we can end up stale entries from when
we previously offlined the CPU.
This does this invalidate as well as unregistering the buffer with
PHYP before we offline the cpu. Tested and fixes crashes seen on
970MP (thanks to tonyb) and POWER5.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
These two instructions exceptionally take a single precision register
as their operand. This means we can't use vfp_get_dm() to read the
register number - we need to use vfp_get_sm() instead. Add a flag to
indicate this exception to the general rule.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The new network driver fec_mpc52xx will not work on efika because the
firmware does not provide all required properties.
http://www.powerdeveloper.org/asset/by-id/46 has a Forth script to
create more properties. But only the phy stuff is required to get a
working network.
This should go into the kernel because its appearently
impossible to boot the script via tftp and then load the real boot
binary (yaboot or zimage).
Signed-off-by: Olaf Hering <olaf@aepfle.de>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
With CPU_HOTPLUG=n:
WARNING: vmlinux.o(.text+0x104f8): Section mismatch: reference to .init.text:fork_idle (between
'do_fork_idle' and 'lapic_timer_broadcast')
do_fork_idle() needs to be __cpuinit. It can be static as well.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'upstream' of git://ftp.linux-mips.org/pub/scm/upstream-linus:
[MIPS] Fix CONFIG_BOOT_RAW.
[MIPS] Assume R4000/R4400 newer than 3.0 don't have the mfc0 count bug
[MIPS] Fix IP32 breakage
[MIPS] Alchemy: Fix use of __init code bug exposed by modpost warning
[MIPS] Move inclusing of kernel/time/Kconfig menu to appropriate place
This seems as reasonable assumption and gets some SNI machines to work
which currently must rely on the cp0 counter as clocksource.
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
- suppress master aborts during config read
- set io_map_base
- only fixup end of iomem resource to avoid failing request_resource
in serial driver
- killed useless setting of crime_int bit, which caused wrong interrupts
- use physcial address for serial port platform device and let 8250
driver do the ioremap
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
WARNING: vmlinux.o(.text+0x1ca608): Section mismatch: reference to
.init.text: add_wired_entry (between 'config_access' and 'config_read')
by refactoring the code calling add_wired_entry() from config_access() to
a separate function which is called from aau1x_pci_setup(). While at it:
- make some unnecassarily global variables 'static';
- fix the letter case, whitespace, etc. in the comments...
Signed-off-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
CONFIG_NO_HZ, CONFIG_HIGH_RES_TIMERS should be selected in "Kernel
type" menu, not in "CPU selection" menu.
Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Jesper Nilsson
Steven Rostedt
Linus Torvalds
Len Brown
Atsushi Nemoto
WANG Cong
Dmitri Vorobiev
Vitaly Wool
Thomas Bogendoerfer
Michael Neuling
Russell King
Olaf Hering
Thomas Gleixner
Ralf Baechle
Sergei Shtylyov
Jan Altenberg