do_notify_resume() may be called on irq or exception
exit. But at that time the exception has already called
rcu_user_enter() and the irq has already called rcu_irq_exit().

Since it can use RCU read side critical section, we must call
rcu_user_exit() before doing anything there. Then we must call
back rcu_user_enter() after this function because we know we are
going to userspace from there.

This complete support for userspace RCU extended quiescent state
in x86-64.
Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
Cc: Alessio Igor Bogani <abogani@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Avi Kivity <avi@redhat.com>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Geoff Levand <geoff@infradead.org>
Cc: Gilad Ben Yossef <gilad@benyossef.com>
Cc: Hakan Akkan <hakanakkan@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Kevin Hilman <khilman@ti.com>
Cc: Max Krasnyansky <maxk@qualcomm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephen Hemminger <shemminger@vyatta.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Sven-Thorsten Dietrich <thebigcorporation@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: NJosh Triplett <josh@joshtriplett.org>

This way we can exit the RCU extended quiescent state before
we schedule a new task from irq/exception exit.
Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
Cc: Alessio Igor Bogani <abogani@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Avi Kivity <avi@redhat.com>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Geoff Levand <geoff@infradead.org>
Cc: Gilad Ben Yossef <gilad@benyossef.com>
Cc: Hakan Akkan <hakanakkan@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Kevin Hilman <khilman@ti.com>
Cc: Max Krasnyansky <maxk@qualcomm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephen Hemminger <shemminger@vyatta.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Sven-Thorsten Dietrich <thebigcorporation@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: NJosh Triplett <josh@joshtriplett.org>

Add necessary hooks to x86 exception for userspace
RCU extended quiescent state support.

This includes traps, page fault, debug exceptions, etc...
Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
Cc: Alessio Igor Bogani <abogani@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Avi Kivity <avi@redhat.com>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Geoff Levand <geoff@infradead.org>
Cc: Gilad Ben Yossef <gilad@benyossef.com>
Cc: Hakan Akkan <hakanakkan@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Kevin Hilman <khilman@ti.com>
Cc: Max Krasnyansky <maxk@qualcomm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephen Hemminger <shemminger@vyatta.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Sven-Thorsten Dietrich <thebigcorporation@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>

There is some unnatural label based layout in this function.
Convert the unnecessary goto to readable conditional blocks.
Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Ingo Molnar <mingo@kernel.org>

Add syscall slow path hooks to notify syscall entry
and exit on CPUs that want to support userspace RCU
extended quiescent state.
Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
Cc: Alessio Igor Bogani <abogani@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Avi Kivity <avi@redhat.com>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Geoff Levand <geoff@infradead.org>
Cc: Gilad Ben Yossef <gilad@benyossef.com>
Cc: Hakan Akkan <hakanakkan@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Kevin Hilman <khilman@ti.com>
Cc: Max Krasnyansky <maxk@qualcomm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephen Hemminger <shemminger@vyatta.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Sven-Thorsten Dietrich <thebigcorporation@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: NJosh Triplett <josh@joshtriplett.org>

Clear the syscalls hook of a task when it's scheduled out so that if
the task migrates, it doesn't run the syscall slow path on a CPU
that might not need it.

Also set the syscalls hook on the next task if needed.
Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
Cc: Alessio Igor Bogani <abogani@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Avi Kivity <avi@redhat.com>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Geoff Levand <geoff@infradead.org>
Cc: Gilad Ben Yossef <gilad@benyossef.com>
Cc: Hakan Akkan <hakanakkan@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Kevin Hilman <khilman@ti.com>
Cc: Max Krasnyansky <maxk@qualcomm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephen Hemminger <shemminger@vyatta.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Sven-Thorsten Dietrich <thebigcorporation@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: NJosh Triplett <josh@joshtriplett.org>

Create a new config option under the RCU menu that put
CPUs under RCU extended quiescent state (as in dynticks
idle mode) when they run in userspace. This require
some contribution from architectures to hook into kernel
and userspace boundaries.
Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
Cc: Alessio Igor Bogani <abogani@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Avi Kivity <avi@redhat.com>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Geoff Levand <geoff@infradead.org>
Cc: Gilad Ben Yossef <gilad@benyossef.com>
Cc: Hakan Akkan <hakanakkan@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Kevin Hilman <khilman@ti.com>
Cc: Max Krasnyansky <maxk@qualcomm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephen Hemminger <shemminger@vyatta.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Sven-Thorsten Dietrich <thebigcorporation@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: NJosh Triplett <josh@joshtriplett.org>

Traditionally, the entire idle task served as an RCU quiescent state.
But when RCU read side critical sections started appearing within the
idle loop, this traditional strategy became untenable.  The fix was to
create new RCU APIs named rcu_idle_enter() and rcu_idle_exit(), which
must be called by each architecture's idle loop so that RCU can tell
when it is safe to ignore a given idle CPU.

Unfortunately, this fix was never applied to ia64, a shortcoming remedied
by this commit.

Reported by: Tony Luck <tony.luck@intel.com>
Signed-off-by: NPaul E. McKenney <paul.mckenney@linaro.org>
Cc: <stable@vger.kernel.org> # 3.3+
Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Tested by: Tony Luck <tony.luck@intel.com>
Reviewed-by: NJosh Triplett <josh@joshtriplett.org>

In the old times, the whole idle task was considered
as an RCU quiescent state. But as RCU became more and
more successful overtime, some RCU read side critical
section have been added even in the code of some
architectures idle tasks, for tracing for example.

So nowadays, rcu_idle_enter() and rcu_idle_exit() must
be called by the architecture to tell RCU about the part
in the idle loop that doesn't make use of rcu read side
critical sections, typically the part that puts the CPU
in low power mode.

This is necessary for RCU to find the quiescent states in
idle in order to complete grace periods.

Add this missing pair of calls in the xtensa's idle loop.
Reported-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: <stable@vger.kernel.org> # 3.3+
Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: NJosh Triplett <josh@joshtriplett.org>

In the old times, the whole idle task was considered
as an RCU quiescent state. But as RCU became more and
more successful overtime, some RCU read side critical
section have been added even in the code of some
architectures idle tasks, for tracing for example.

So nowadays, rcu_idle_enter() and rcu_idle_exit() must
be called by the architecture to tell RCU about the part
in the idle loop that doesn't make use of rcu read side
critical sections, typically the part that puts the CPU
in low power mode.

This is necessary for RCU to find the quiescent states in
idle in order to complete grace periods.

Add this missing pair of calls in scores's idle loop.
Reported-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
Cc: Chen Liqin <liqin.chen@sunplusct.com>
Cc: Lennox Wu <lennox.wu@gmail.com>
Cc: <stable@vger.kernel.org> # 3.3+
Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: NJosh Triplett <josh@joshtriplett.org>

In the old times, the whole idle task was considered
as an RCU quiescent state. But as RCU became more and
more successful overtime, some RCU read side critical
section have been added even in the code of some
architectures idle tasks, for tracing for example.

So nowadays, rcu_idle_enter() and rcu_idle_exit() must
be called by the architecture to tell RCU about the part
in the idle loop that doesn't make use of rcu read side
critical sections, typically the part that puts the CPU
in low power mode.

This is necessary for RCU to find the quiescent states in
idle in order to complete grace periods.

Add this missing pair of calls in the parisc's idle loop.
Reported-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
Cc: James E.J. Bottomley <jejb@parisc-linux.org>
Cc: Helge Deller <deller@gmx.de>
Cc: Parisc <linux-parisc@vger.kernel.org>
Cc: <stable@vger.kernel.org> # 3.3+
Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: NJosh Triplett <josh@joshtriplett.org>

In the old times, the whole idle task was considered
as an RCU quiescent state. But as RCU became more and
more successful overtime, some RCU read side critical
section have been added even in the code of some
architectures idle tasks, for tracing for example.

So nowadays, rcu_idle_enter() and rcu_idle_exit() must
be called by the architecture to tell RCU about the part
in the idle loop that doesn't make use of rcu read side
critical sections, typically the part that puts the CPU
in low power mode.

This is necessary for RCU to find the quiescent states in
idle in order to complete grace periods.

Add this missing pair of calls in the mn10300's idle loop.
Reported-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Koichi Yasutake <yasutake.koichi@jp.panasonic.com>
Cc: <stable@vger.kernel.org> # 3.3+
Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: NDavid Howells <dhowells@redhat.com>
Reviewed-by: NJosh Triplett <josh@joshtriplett.org>

In the old times, the whole idle task was considered
as an RCU quiescent state. But as RCU became more and
more successful overtime, some RCU read side critical
section have been added even in the code of some
architectures idle tasks, for tracing for example.

So nowadays, rcu_idle_enter() and rcu_idle_exit() must
be called by the architecture to tell RCU about the part
in the idle loop that doesn't make use of rcu read side
critical sections, typically the part that puts the CPU
in low power mode.

This is necessary for RCU to find the quiescent states in
idle in order to complete grace periods.

Add this missing pair of calls in the m68k's idle loop.
Reported-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
Acked-by: NGeert Uytterhoeven <geert@linux-m68k.org>
Cc: m68k <linux-m68k@lists.linux-m68k.org>
Cc: <stable@vger.kernel.org> # 3.3+
Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: NJosh Triplett <josh@joshtriplett.org>

In the old times, the whole idle task was considered
as an RCU quiescent state. But as RCU became more and
more successful overtime, some RCU read side critical
section have been added even in the code of some
architectures idle tasks, for tracing for example.

So nowadays, rcu_idle_enter() and rcu_idle_exit() must
be called by the architecture to tell RCU about the part
in the idle loop that doesn't make use of rcu read side
critical sections, typically the part that puts the CPU
in low power mode.

This is necessary for RCU to find the quiescent states in
idle in order to complete grace periods.

Add this missing pair of calls in the m32r's idle loop.
Reported-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
Cc: Hirokazu Takata <takata@linux-m32r.org>
Cc: <stable@vger.kernel.org> # 3.3+
Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: NJosh Triplett <josh@joshtriplett.org>

In the old times, the whole idle task was considered
as an RCU quiescent state. But as RCU became more and
more successful overtime, some RCU read side critical
section have been added even in the code of some
architectures idle tasks, for tracing for example.

So nowadays, rcu_idle_enter() and rcu_idle_exit() must
be called by the architecture to tell RCU about the part
in the idle loop that doesn't make use of rcu read side
critical sections, typically the part that puts the CPU
in low power mode.

This is necessary for RCU to find the quiescent states in
idle in order to complete grace periods.

Add this missing pair of calls in the h8300's idle loop.
Reported-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: <stable@vger.kernel.org> # 3.3+
Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: NJosh Triplett <josh@joshtriplett.org>

In the old times, the whole idle task was considered
as an RCU quiescent state. But as RCU became more and
more successful overtime, some RCU read side critical
section have been added even in the code of some
architectures idle tasks, for tracing for example.

So nowadays, rcu_idle_enter() and rcu_idle_exit() must
be called by the architecture to tell RCU about the part
in the idle loop that doesn't make use of rcu read side
critical sections, typically the part that puts the CPU
in low power mode.

This is necessary for RCU to find the quiescent states in
idle in order to complete grace periods.

Add this missing pair of calls in the Frv's idle loop.
Reported-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
Cc: David Howells <dhowells@redhat.com>
Cc: <stable@vger.kernel.org> # 3.3+
Acked-by: NDavid Howells <dhowells@redhat.com>
Reviewed-by: NJosh Triplett <josh@joshtriplett.org>

In the old times, the whole idle task was considered
as an RCU quiescent state. But as RCU became more and
more successful overtime, some RCU read side critical
section have been added even in the code of some
architectures idle tasks, for tracing for example.

So nowadays, rcu_idle_enter() and rcu_idle_exit() must
be called by the architecture to tell RCU about the part
in the idle loop that doesn't make use of rcu read side
critical sections, typically the part that puts the CPU
in low power mode.

This is necessary for RCU to find the quiescent states in
idle in order to complete grace periods.

Add this missing pair of calls in the Cris's idle loop.
Reported-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
Cc: Mikael Starvik <starvik@axis.com>
Cc: Jesper Nilsson <jesper.nilsson@axis.com>
Cc: Cris <linux-cris-kernel@axis.com>
Cc: <stable@vger.kernel.org> # 3.3+
Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: NJosh Triplett <josh@joshtriplett.org>

In the old times, the whole idle task was considered
as an RCU quiescent state. But as RCU became more and
more successful overtime, some RCU read side critical
section have been added even in the code of some
architectures idle tasks, for tracing for example.

So nowadays, rcu_idle_enter() and rcu_idle_exit() must
be called by the architecture to tell RCU about the part
in the idle loop that doesn't make use of rcu read side
critical sections, typically the part that puts the CPU
in low power mode.

This is necessary for RCU to find the quiescent states in
idle in order to complete grace periods.

Add this missing pair of calls in the Alpha's idle loop.
Reported-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
Tested-by: NMichael Cree <mcree@orcon.net.nz>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Matt Turner <mattst88@gmail.com>
Cc: alpha <linux-alpha@vger.kernel.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: <stable@vger.kernel.org> # 3.3+
Reviewed-by: NJosh Triplett <josh@joshtriplett.org>

cpu_idle() is called on the boot CPU by the init code with
preemption disabled. But the cpu_idle() function in alpha
doesn't handle this when it calls schedule() directly.

Fix it by converting it into schedule_preempt_disabled().

Also disable preemption before calling cpu_idle() from
secondary CPU entry code to stay consistent with this
state.
Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
Tested-by: NMichael Cree <mcree@orcon.net.nz>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Matt Turner <mattst88@gmail.com>
Cc: alpha <linux-alpha@vger.kernel.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: NJosh Triplett <josh@joshtriplett.org>

If arch/x86/kernel/cpuid.c is a module, a CPU might offline or online
between the for_each_online_cpu() loop and the call to
register_hotcpu_notifier in cpuid_init or the call to
unregister_hotcpu_notifier in cpuid_exit.  The potential races can
lead to leaks/duplicates, attempts to destroy non-existant devices, or
random pointer dereferences.

For example, in cpuid_exit if:

        for_each_online_cpu(cpu)
                cpuid_device_destroy(cpu);
        class_destroy(cpuid_class);
        __unregister_chrdev(CPUID_MAJOR, 0, NR_CPUS, "cpu/cpuid");
        <----- CPU onlines
        unregister_hotcpu_notifier(&cpuid_class_cpu_notifier);

the hotcpu notifier will attempt to create a device for the
cpuid_class, which the module already destroyed.

This fix surrounds for_each_online_cpu and register_hotcpu_notifier or
unregister_hotcpu_notifier with get_online_cpus+put_online_cpus.

Tested on a VM.
Signed-off-by: NSilas Boyd-Wickizer <sbw@mit.edu>
Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>

If arch/x86/kernel/msr.c is a module, a CPU might offline or online
between the for_each_online_cpu(i) loop and the call to
register_hotcpu_notifier in msr_init or the call to
unregister_hotcpu_notifier in msr_exit. The potential races can lead
to leaks/duplicates, attempts to destroy non-existant devices, or
random pointer dereferences.

For example, in msr_init if:

        for_each_online_cpu(i) {
                err = msr_device_create(i);
                if (err != 0)
                        goto out_class;
        }
        <----- CPU offlines
        register_hotcpu_notifier(&msr_class_cpu_notifier);

and the CPU never onlines before msr_exit, then the module will never
call msr_device_destroy for the associated CPU.

This fix surrounds for_each_online_cpu and register_hotcpu_notifier or
unregister_hotcpu_notifier with get_online_cpus+put_online_cpus.

Tested on a VM.
Signed-off-by: NSilas Boyd-Wickizer <sbw@mit.edu>
Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>

In case of error, function module_alloc() in other platform never
returns ERR_PTR(), and all of the user only check for NULL, so
we'd better return NULL instead of ERR_PTR().

dpatch engine is used to auto generated this patch.
(https://github.com/weiyj/dpatch)
Signed-off-by: NWei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

GNU Binutils 2.20.1 generates .eh_frame sections that uses R_SPARC_DISP32.
Signed-off-by: NAndreas Larsson <andreas@gaisler.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

kcmp has appeared on x86, but has not been noticed because
checksyscalls.sh is broken at the moment.  Reserve ARM syscall 378
for this should we ever need it, and add an __IGNORE entry for this
unimplemented syscall.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

While building the SUSE kernel packages, which build the scripts,
make clean, and then build everything, we have been running into spurious
build failures. We tracked them down to a simple dependency issue:

$ make mrproper
  CLEAN   arch/x86/tools
  CLEAN   scripts/basic
$ cp patches/config/x86_64/desktop .config
$ make archscripts
  HOSTCC  arch/x86/tools/relocs
/bin/sh: scripts/basic/fixdep: No such file or directory
make[3]: *** [arch/x86/tools/relocs] Error 1
make[2]: *** [archscripts] Error 2
make[1]: *** [sub-make] Error 2
make: *** [all] Error 2

This was introduced by commit
6520fe55 (x86, realmode: 16-bit real-mode code support for relocs),
which added the archscripts dependency to archprepare.

This patch adds the scripts_basic dependency to the x86 archscripts.
Signed-off-by: NJeff Mahoney <jeffm@suse.com>
Signed-off-by: NMichal Marek <mmarek@suse.cz>

Running cpufreq driver on imx6q, the following warning is seen.

$ BUG: sleeping function called from invalid context at kernel/mutex.c:269

<snip>

stack backtrace:
Backtrace:
[<80011d64>] (dump_backtrace+0x0/0x10c) from [<803fc164>] (dump_stack+0x18/0x1c)
 r6:bf8142e0 r5:bf814000 r4:806ac794 r3:bf814000
[<803fc14c>] (dump_stack+0x0/0x1c) from [<803fd444>] (print_usage_bug+0x250/0x2b
8)
[<803fd1f4>] (print_usage_bug+0x0/0x2b8) from [<80060f90>] (mark_lock+0x56c/0x67
0)
[<80060a24>] (mark_lock+0x0/0x670) from [<80061a20>] (__lock_acquire+0x98c/0x19b
4)
[<80061094>] (__lock_acquire+0x0/0x19b4) from [<80062f14>] (lock_acquire+0x68/0x
7c)
[<80062eac>] (lock_acquire+0x0/0x7c) from [<80400f28>] (mutex_lock_nested+0x78/0
x344)
 r7:00000000 r6:bf872000 r5:805cc858 r4:805c2a04
[<80400eb0>] (mutex_lock_nested+0x0/0x344) from [<803089ac>] (clk_get_rate+0x1c/
0x58)
[<80308990>] (clk_get_rate+0x0/0x58) from [<80013c48>] (twd_update_frequency+0x1
8/0x50)
 r5:bf253d04 r4:805cadf4
[<80013c30>] (twd_update_frequency+0x0/0x50) from [<80068e20>] (generic_smp_call
_function_single_interrupt+0xd4/0x13c)
 r4:bf873ee0 r3:80013c30
[<80068d4c>] (generic_smp_call_function_single_interrupt+0x0/0x13c) from [<80013
34c>] (handle_IPI+0xc0/0x194)
 r8:00000001 r7:00000000 r6:80574e48 r5:bf872000 r4:80593958
[<8001328c>] (handle_IPI+0x0/0x194) from [<800084e8>] (gic_handle_irq+0x58/0x60)
 r8:00000000 r7:bf873f8c r6:bf873f58 r5:80593070 r4:f4000100
r3:00000005
[<80008490>] (gic_handle_irq+0x0/0x60) from [<8000e124>] (__irq_svc+0x44/0x60)
Exception stack(0xbf873f58 to 0xbf873fa0)
3f40:                                                       00000001 00000001
3f60: 00000000 bf814000 bf872000 805cab48 80405aa4 80597648 00000000 412fc09a
3f80: bf872000 bf873fac bf873f70 bf873fa0 80063844 8000f1f8 20000013 ffffffff
 r6:ffffffff r5:20000013 r4:8000f1f8 r3:bf814000
[<8000f1b8>] (default_idle+0x0/0x4c) from [<8000f428>] (cpu_idle+0x98/0x114)
[<8000f390>] (cpu_idle+0x0/0x114) from [<803f9834>] (secondary_start_kernel+0x11
c/0x140)
[<803f9718>] (secondary_start_kernel+0x0/0x140) from [<103f9234>] (0x103f9234)
 r6:10c03c7d r5:0000001f r4:4f86806a r3:803f921c

It looks that the warning is caused by that twd_update_frequency() gets
called from an atomic context while it calls clk_get_rate() where a
mutex gets held.

To fix the warning, let's convert common clk users over to clk notifiers
in place of CPUfreq notifiers.  This works out nicely for Cortex-A9
MPcore designs that scale all CPUs at the same frequency.

Platforms that have not been converted to the common clk framework and
support CPUfreq will rely on the old mechanism.  Once these platforms
are converted over fully then we can remove the CPUfreq-specific bits
for good.
Signed-off-by: NMike Turquette <mturquette@linaro.org>
Signed-off-by: NShawn Guo <shawn.guo@linaro.org>
Reviewed-by: NLinus Walleij <linus.walleij@linaro.org>
Reviewed-by: NUlf Hansson <ulf.hansson@linaro.org>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

As the initial domain we are able to search/map certain regions
of memory to harvest configuration data. For all low-level we
use ACPI tables - for interrupts we use exclusively ACPI _PRT
(so DSDT) and MADT for INT_SRC_OVR.

The SMP MP table is not used at all. As a matter of fact we do
not even support machines that only have SMP MP but no ACPI tables.

Lets follow how Moorestown does it and just disable searching
for BIOS SMP tables.

This also fixes an issue on HP Proliant BL680c G5 and DL380 G6:

9f->100 for 1:1 PTE
Freeing 9f-100 pfn range: 97 pages freed
1-1 mapping on 9f->100
.. snip..
e820: BIOS-provided physical RAM map:
Xen: [mem 0x0000000000000000-0x000000000009efff] usable
Xen: [mem 0x000000000009f400-0x00000000000fffff] reserved
Xen: [mem 0x0000000000100000-0x00000000cfd1dfff] usable
.. snip..
Scan for SMP in [mem 0x00000000-0x000003ff]
Scan for SMP in [mem 0x0009fc00-0x0009ffff]
Scan for SMP in [mem 0x000f0000-0x000fffff]
found SMP MP-table at [mem 0x000f4fa0-0x000f4faf] mapped at [ffff8800000f4fa0]
(XEN) mm.c:908:d0 Error getting mfn 100 (pfn 5555555555555555) from L1 entry 0000000000100461 for l1e_owner=0, pg_owner=0
(XEN) mm.c:4995:d0 ptwr_emulate: could not get_page_from_l1e()
BUG: unable to handle kernel NULL pointer dereference at           (null)
IP: [<ffffffff81ac07e2>] xen_set_pte_init+0x66/0x71
. snip..
Pid: 0, comm: swapper Not tainted 3.6.0-rc6upstream-00188-gb6fb969-dirty #2 HP ProLiant BL680c G5
.. snip..
Call Trace:
 [<ffffffff81ad31c6>] __early_ioremap+0x18a/0x248
 [<ffffffff81624731>] ? printk+0x48/0x4a
 [<ffffffff81ad32ac>] early_ioremap+0x13/0x15
 [<ffffffff81acc140>] get_mpc_size+0x2f/0x67
 [<ffffffff81acc284>] smp_scan_config+0x10c/0x136
 [<ffffffff81acc2e4>] default_find_smp_config+0x36/0x5a
 [<ffffffff81ac3085>] setup_arch+0x5b3/0xb5b
 [<ffffffff81624731>] ? printk+0x48/0x4a
 [<ffffffff81abca7f>] start_kernel+0x90/0x390
 [<ffffffff81abc356>] x86_64_start_reservations+0x131/0x136
 [<ffffffff81abfa83>] xen_start_kernel+0x65f/0x661
(XEN) Domain 0 crashed: 'noreboot' set - not rebooting.

which is that ioremap would end up mapping 0xff using _PAGE_IOMAP
(which is what early_ioremap sticks as a flag) - which meant
we would get MFN 0xFF (pte ff461, which is OK), and then it would
also map 0x100 (b/c ioremap tries to get page aligned request, and
it was trying to map 0xf4fa0 + PAGE_SIZE - so it mapped the next page)
as _PAGE_IOMAP. Since 0x100 is actually a RAM page, and the _PAGE_IOMAP
bypasses the P2M lookup we would happily set the PTE to 1000461.
Xen would deny the request since we do not have access to the
Machine Frame Number (MFN) of 0x100. The P2M[0x100] is for example
0x80140.

CC: stable@vger.kernel.org
Fixes-Oracle-Bugzilla: https://bugzilla.oracle.com/bugzilla/show_bug.cgi?id=13665Acked-by: NJan Beulich <jbeulich@suse.com>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

This patch updates the existing Intel IvyBridge (model 58)
support with proper PEBS event constraints. It cannot reuse
the same as SandyBridge because some events (0xd3) are
specific to IvyBridge.

Also there is no UOPS_DISPATCHED.THREAD on IVB, so do not
populate the PERF_COUNT_HW_STALLED_CYCLES_BACKEND mapping.
Signed-off-by: NStephane Eranian <eranian@google.com>
Cc: peterz@infradead.org
Cc: ak@linux.intel.com
Link: http://lkml.kernel.org/r/20120910230701.GA5898@quadSigned-off-by: NIngo Molnar <mingo@kernel.org>

Since i.MX has SPARSE_IRQ enabled the i.MX25 timer is broken. This
is because the internal irqs now start at an offset of NR_IRQS_LEGACY.
The patch fixed this up, but missed the i.MX25 timer which used a
hardcoded value instead of a define. This patch introduces a define
for the timer irq and uses it.

This is broken since introduced with 3.6-rc1:

| commit 8842a9e2
| Author: Shawn Guo <shawn.guo@linaro.org>
| Date:   Thu Jun 14 11:16:14 2012 +0800
|
|    ARM: imx: enable SPARSE_IRQ for imx platform
Signed-off-by: NSascha Hauer <s.hauer@pengutronix.de>
Acked-by: NShawn Guo <shawn.guo@linaro.org>

Since commit eb92044e (ARM i.MX3: Make ccm base address a variable )
it is necessary to pass the CCM register base as a variable.

Fix the CCM register access in mach-armadillo5x0 by passing mx3_ccm_base and
avoid illegal accesses.

Also applies to v3.5
Reported-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NFabio Estevam <fabio.estevam@freescale.com>
Acked-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NSascha Hauer <s.hauer@pengutronix.de>
Cc: stable@vger.kernel.org

As Al notes, we missed a TIF_NOTIFY_RESUME check which caused any
handlers without TIF_SIGPENDING also set to skip the notification:

	Looks like while it is in the relevant masks *and* checked in
	do_notify_resume() both on 32bit and 64bit variants since commit
	ab99c733 ("sh: Make syscall tracer
	use tracehook notifiers, add TIF_NOTIFY_RESUME.") they are
	actually *not* reached without simulataneous SIGPENDING, since
	the actual glue in the callers had not been updated back then and
	still checks for _TIF_SIGPENDING alone when deciding whether to
	hit do_notify_resume() or not.
Reported-by: NNobuhiro Iwamatsu <nobuhiro.iwamatsu.yj@renesas.com>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Tested-by: NNobuhiro Iwamatsu <nobuhiro.iwamatsu.yj@renesas.com>
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

Correct interrupt settings of sh_mmc:int and sh_mmc:error in board-kzm9g.c.
Signed-off-by: NTetsuyuki Kobayashi <koba@kmckk.co.jp>
Acked-by: NKuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: NSimon Horman <horms@verge.net.au>

The spinlock clocks_lock can be held during ISR, hence it is not safe to
hold that lock with disabling interrupts.

It fixes following potential deadlock.

=========================================================
[ INFO: possible irq lock inversion dependency detected ]
3.6.0-rc4+ #2 Not tainted
---------------------------------------------------------
swapper/0/1 just changed the state of lock:
 (&(&host->lock)->rlock){-.....}, at: [<c027fb0d>] sdhci_irq+0x15/0x564
but this lock took another, HARDIRQ-unsafe lock in the past:
 (clocks_lock){+.+...}

and interrupts could create inverse lock ordering between them.

other info that might help us debug this:
 Possible interrupt unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(clocks_lock);
                               local_irq_disable();
                               lock(&(&host->lock)->rlock);
                               lock(clocks_lock);
  <Interrupt>
    lock(&(&host->lock)->rlock);

 *** DEADLOCK ***
Signed-off-by: NTushar Behera <tushar.behera@linaro.org>
Signed-off-by: NKukjin Kim <kgene.kim@samsung.com>

Signed-off-by: NJean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Tested-by: NBo Shen <voice.shen@atmel.com>
Signed-off-by: NNicolas Ferre <nicolas.ferre@atmel.com>

The s390 page-table walk code, used for user copy and futex, currently
cannot handle huge pages. As far as user copy is concerned, that is
not really a problem because those functions will only be used on old
hardware that has no huge page support. But the futex code will also
use pagetable walk functions on current hardware when user space runs
in primary space mode. So, if a futex sits in a huge page, the futex
operation on it will result in a page fault loop or even data
corruption.

This patch adds the code for resolving huge page mappings in the user
access pagetable walk code on s390.
Signed-off-by: NGerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

From 0cdf3aff, "ARM: SAMSUNG: use spin_lock_irqsave() in
clk_{enable,disable}":

  The clk_enable()and clk_disable() can be used process and ISR either.
  And actually it is used for real product and other platforms use it
  now. So spin_lock_irqsave() should be used instead.

We need to make a similar change in clk_set_parent(). Otherwise,
you can potentially get spinlock recursion:

BUG: spinlock recursion on CPU#0, kinteractive/68
 lock: 807832a8, .magic: dead4ead, .owner: kinteractive/68, .owner_cpu: 0
[<80015f54>] (unwind_backtrace+0x0/0x128) from [<804f2914>] (dump_stack+0x20/0x24)
[<804f2914>] (dump_stack+0x20/0x24) from [<804f57b8>] (spin_dump+0x80/0x94)
[<804f57b8>] (spin_dump+0x80/0x94) from [<804f57f8>] (spin_bug+0x2c/0x30)
[<804f57f8>] (spin_bug+0x2c/0x30) from [<80222730>] (do_raw_spin_lock+0x54/0x150)
[<80222730>] (do_raw_spin_lock+0x54/0x150) from [<804f96ec>] (_raw_spin_lock_irqsave+0x20/0x28)
[<804f96ec>] (_raw_spin_lock_irqsave+0x20/0x28) from [<80022ea4>] (clk_enable+0x3c/0x84)
[<80022ea4>] (clk_enable+0x3c/0x84) from [<8038336c>] (s5p_mfc_clock_on+0x60/0x74)
[<8038336c>] (s5p_mfc_clock_on+0x60/0x74) from [<8038645c>] (s5p_mfc_read_info+0x20/0x38)
[<8038645c>] (s5p_mfc_read_info+0x20/0x38) from [<8037ca3c>] (s5p_mfc_handle_frame+0x2e4/0x4bc)
[<8037ca3c>] (s5p_mfc_handle_frame+0x2e4/0x4bc) from [<8037d420>] (s5p_mfc_irq+0x1ec/0x6cc)
[<8037d420>] (s5p_mfc_irq+0x1ec/0x6cc) from [<8007fc74>] (handle_irq_event_percpu+0x8c/0x244)
[<8007fc74>] (handle_irq_event_percpu+0x8c/0x244) from [<8007fe78>] (handle_irq_event+0x4c/0x6c)
[<8007fe78>] (handle_irq_event+0x4c/0x6c) from [<80082dd8>] (handle_fasteoi_irq+0xe4/0x150)
[<80082dd8>] (handle_fasteoi_irq+0xe4/0x150) from [<8007f424>] (generic_handle_irq+0x3c/0x50)
[<8007f424>] (generic_handle_irq+0x3c/0x50) from [<8000f7c4>] (handle_IRQ+0x88/0xc8)
[<8000f7c4>] (handle_IRQ+0x88/0xc8) from [<80008564>] (gic_handle_irq+0x44/0x68)
[<80008564>] (gic_handle_irq+0x44/0x68) from [<8000e400>] (__irq_svc+0x40/0x60)
Exception stack(0xef3cbe68 to 0xef3cbeb0)
[<8000e400>] (__irq_svc+0x40/0x60) from [<80022cfc>] (clk_set_parent+0x30/0x74)
[<80022cfc>] (clk_set_parent+0x30/0x74) from [<803ac7f8>] (set_apll.isra.0+0x28/0xb0)
[<803ac7f8>] (set_apll.isra.0+0x28/0xb0) from [<803ac8e4>] (exynos5250_set_frequency+0x64/0xb8)
[<803ac8e4>] (exynos5250_set_frequency+0x64/0xb8) from [<803ac280>] (exynos_target+0x1b0/0x220)
[<803ac280>] (exynos_target+0x1b0/0x220) from [<803a4a0c>] (__cpufreq_driver_target+0xb0/0xd4)
[<803a4a0c>] (__cpufreq_driver_target+0xb0/0xd4) from [<803aab80>] (cpufreq_interactive_updown_task+0x214/0x264)
[<803aab80>] (cpufreq_interactive_updown_task+0x214/0x264) from [<80047d04>] (kthread+0x9c/0xa8)
[<80047d04>] (kthread+0x9c/0xa8) from [<8000fa48>] (kernel_thread_exit+0x0/0x8)
Signed-off-by: NMandeep Singh Baines <msb@chromium.org>
Suggested-by: NSunil Mazhavanchery <sunilm@samsung.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-samsung-soc@vger.kernel.org
Cc: Ben Dooks <ben-linux@fluff.org>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Minho Ban <mhban@samsung.com>
Cc: Jaecheol Lee <jc.lee@samsung.com>
Cc: Sunyoung Kang <sy0816.kang@samsung.com>
Cc: Olof Johansson <olofj@chromium.org>
Signed-off-by: NKukjin Kim <kgene.kim@samsung.com>

48d480b0 [[MIPS] Malta: Fix off by one bug in interrupt
handler.] did not take in account that irq_ffs() will also return 0 if for some reason
the set of pending interrupts happens to be empty.

This is trivial to trigger with a RM5261 CPU module running a 64-bit kernel and results
in something like the following:

CPU 0 Unable to handle kernel paging request at virtual address 0000000000000000, epc == ffffffff801772d0, ra == ffffffff8017ad24
Oops[#1]:
Cpu 0
$ 0   : 0000000000000000 ffffffff9000a4e0 ffffffff9000a4e0 ffffffff9000a4e0
$ 4   : ffffffff80592be0 0000000000000000 00000000000000d6 ffffffff80322ed0
$ 8   : ffffffff805fe538 0000000000000000 ffffffff9000a4e0 ffffffff80590000
$12   : 00000000000000d6 0000000000000000 ffffffff80600000 ffffffff805fe538
$16   : 0000000000000000 0000000000000010 ffffffff80592be0 0000000000000010
$20   : 0000000000000000 0000000000500001 0000000000000000 ffffffff8051e078
$24   : 0000000000000028 ffffffff803226e8
$28   : 9800000003828000 980000000382b900 ffffffff8051e060 ffffffff8017ad24
Hi    : 0000000000000000
Lo    : 0000006388974000
epc   : ffffffff801772d0 handle_irq_event_percpu+0x70/0x2f0
    Not tainted
ra    : ffffffff8017ad24 handle_percpu_irq+0x54/0x88
Status: 9000a4e2    KX SX UX KERNEL EXL
Cause : 00808008
BadVA : 0000000000000000
PrId  : 000028a0 (Nevada)
Modules linked in:
Process init (pid: 1, threadinfo=9800000003828000, task=9800000003827968, tls=0000000077087490)
Stack : ffffffff80592be0 ffffffff8058d248 0000000000000040 0000000000000000
        ffffffff80613340 0000000000500001 ffffffff805a0000 0000000000000882
        9800000003b89000 ffffffff8017ad24 00000000000000d5 0000000000000010
        ffffffff9000a4e1 ffffffff801769f4 ffffffff9000a4e0 ffffffff801037f8
        0000000000000000 ffffffff80101c44 0000000000000000 ffffffff9000a4e0
        0000000000000000 9000000018000000 90000000180003f9 0000000000000001
        0000000000000000 00000000000000ff 0000000000000018 0000000000000001
        0000000000000001 00000000003fffff 0000000000000020 ffffffff802cf7ac
        ffffffff80208918 000000007fdadf08 ffffffff80612d88 ffffffff9000a4e1
        0000000000000040 0000000000000000 ffffffff80613340 0000000000500001
        ...
Call Trace:
[<ffffffff801772d0>] handle_irq_event_percpu+0x70/0x2f0
[<ffffffff8017ad24>] handle_percpu_irq+0x54/0x88
[<ffffffff801769f4>] generic_handle_irq+0x44/0x60
[<ffffffff801037f8>] do_IRQ+0x48/0x70
[<ffffffff80101c44>] ret_from_irq+0x0/0x4
[<ffffffff80326170>] serial8250_startup+0x310/0x870
[<ffffffff8032175c>] uart_startup.part.7+0x9c/0x330
[<ffffffff80321b4c>] uart_open+0x15c/0x1b0
[<ffffffff80302034>] tty_open+0x1fc/0x720
[<ffffffff801bffac>] chrdev_open+0x7c/0x180
[<ffffffff801b9ab8>] do_dentry_open.isra.14+0x288/0x390
[<ffffffff801bac5c>] nameidata_to_filp+0x5c/0xc0
[<ffffffff801ca700>] do_last.isra.33+0x330/0x8f0
[<ffffffff801caf3c>] path_openat+0xbc/0x440
[<ffffffff801cb3c8>] do_filp_open+0x38/0xa8
[<ffffffff801bade4>] do_sys_open+0x124/0x218
[<ffffffff80110538>] handle_sys+0x118/0x13c

Code: 02d5a825  12800012  02a0b02d <de820000> de850008  0040f809  0220202d  0040a82d  40026000
---[ end trace 5d8e7b9a86badd2d ]---
Kernel panic - not syncing: Fatal exception in interrupt
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

This patch zeroes the SCTLR.TRE bit prior to setting the mapping as
cacheable for ARMv7 cores in the decompressor, ensuring that the
memory region attributes are obtained from the C and B bits, not from
the page tables.

Cc: Nicolas Pitre <nico@fluxnic.net>
Reviewed-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NMatthew Leach <matthew.leach@arm.com>
Signed-off-by: NWill Deacon <will.deacon@arm.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

The managed clk functions are currently only available when the generic clk
lookup framework is build. But the managed clk functions are merely wrappers
around clk_get and clk_put and do not depend on any specifics of the generic
lookup functions and there are still quite a few custom implementations of the
clk API. So make the managed functions available whenever the clk API is
implemented.

The patch also removes the custom implementation of devm_clk_get for the
coldfire platform.
Signed-off-by: NLars-Peter Clausen <lars@metafoo.de>
Acked-by: NGreg Ungerer <gerg@uclinux.org>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

 YAMON requires and enforces the RTC Data Mode (Register B, DM bit) to
binary, that is the bit is set every time the board goes through the
firmware bootstrap sequence.  Likewise its calendar manipulation commands
interpret or set the RTC registers unconditionally as binary, never
actually checking what the value of the DM bit is, under the (correct)
assumption that it has been previously set, to indicate the binary mode.

 A change to Linux a while ago however introduced a platform-specific
tweak that clears that bit and therefore forces the data mode to BCD.
This causes clock corruption and misinterpretation that has to be fixed up
by user-mode tools in system startup scripts as the initial clock is often
incorrect according to the BCD interpretation forced.

 This change removes the hack; a comment included refers to alarm code,
but even if it was broken at one point by requiring the BCD mode, it
should have been trivially corrected and even if not, given how rarely the
alarm feature is used, that was not really a reasonable justification to
break the system clock that is indeed used by virtually everything.  And
either way the alarm code has been since fixed anyway.
Signed-off-by: NMaciej W. Rozycki <macro@codesourcery.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/4336/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>