Uses of RCU for dynamically changeable NMI handlers need to use the new
rcu_dereference() and rcu_assign_pointer() facilities.  This change makes
it clear that these uses are safe from a memory-barrier viewpoint, but the
main purpose is to document exactly what operations are being protected by
RCU.  This has been tested on x86 and x86-64, which are the only
architectures affected by this change.

Signed-off-by: <paulmck@us.ibm.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Move some more frequently read variables that showed up during some of our
performance tests as sometimes ending up in hot cachelines to the
read_mostly section.

Fix: Move the __read_mostly from before hpet_usec_quotient to follow the
variable like the other uses of __read_mostly.
Signed-off-by: NAlok N Kataria <alokk@calsoftinc.com>
Signed-off-by: NChristoph Lameter <christoph@scalex86.org>
Signed-off-by: NShai Fultheim <shai@scalex86.org>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

This patch adds a new kernel debug feature: CONFIG_DETECT_SOFTLOCKUP.

When enabled then per-CPU watchdog threads are started, which try to run
once per second.  If they get delayed for more than 10 seconds then a
callback from the timer interrupt detects this condition and prints out a
warning message and a stack dump (once per lockup incident).  The feature
is otherwise non-intrusive, it doesnt try to unlock the box in any way, it
only gets the debug info out, automatically, and on all CPUs affected by
the lockup.
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NNishanth Aravamudan <nacc@us.ibm.com>
Signed-Off-By: NMatthias Urlichs <smurf@smurf.noris.de>
Signed-off-by: NRichard Purdie <rpurdie@rpsys.net>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

This allows a valid iommu placed immediately after memory to work, to be
recognized as after the last byte of memory and not overlapping it.
Signed-off-by: NEric W. Biederman <ebiederm@xmission.com>
Acked-by: NAndi Kleen <ak@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Need to create sysfs only for cpus that are present.  Without which we see
NR_CPUS entries created when we have CONFIG_HOTPLUG and CONFIG_HOTPLUG_CPU
enabled.
Signed-off-by: NAshok Raj <ashok.raj@intel.com>
Acked-by: NAndi Kleen <ak@muc.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Need to ensure we dont get prempted when we clear ourself from mask when using
clustered mode genapic code.
Signed-off-by: NAshok Raj <ashok.raj@intel.com>
Acked-by: NAndi Kleen <ak@muc.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Up to date I've been using the GS value to determine the processor number
in dumps from show_regs, however this can be cumbersome to do if you don't
have the vmlinux to verify with the address of cpu_pda, how about the
following?  I considered using hard_smp_processor_id for robustness but we
already dereference current so we're already relying on MSR_GS_BASE being
sane.
Signed-off-by: NZwane Mwaikambo <zwane@arm.linux.org.uk>
Acked-by: NAndi Kleen <ak@muc.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

When handling writes to /proc/irq, current code is re-programming rte
entries directly. This is not recommended and could potentially cause
chipset's to lockup, or cause missing interrupts.

CONFIG_IRQ_BALANCE does this correctly, where it re-programs only when the
interrupt is pending. The same needs to be done for /proc/irq handling as well.
Otherwise user space irq balancers are really not doing the right thing.

- Changed pending_irq_balance_cpumask to pending_irq_migrate_cpumask for
  lack of a generic name.
- added move_irq out of IRQ_BALANCE, and added this same to X86_64
- Added new proc handler for write, so we can do deferred write at irq
  handling time.
- Display of /proc/irq/XX/smp_affinity used to display CPU_MASKALL, instead
  it now shows only active cpu masks, or exactly what was set.
- Provided a common move_irq implementation, instead of duplicating
  when using generic irq framework.

Tested on i386/x86_64 and ia64 with CONFIG_PCI_MSI turned on and off.
Tested UP builds as well.

MSI testing: tbd: I have cards, need to look for a x-over cable, although I
did test an earlier version of this patch.  Will test in a couple days.
Signed-off-by: NAshok Raj <ashok.raj@intel.com>
Acked-by: NZwane Mwaikambo <zwane@holomorphy.com>
Grudgingly-acked-by: NAndi Kleen <ak@muc.de>
Signed-off-by: NCoywolf Qi Hunt <coywolf@lovecn.org>
Signed-off-by: NAshok Raj <ashok.raj@intel.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Recent "u32 -> pm_message_t" change triggered hidden bug in
ocp_device_suspend.  Fix it to correctly use pm_message_t instead of u32.
Signed-off-by: NEugene Surovegin <ebs@ebshome.net>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Changing CONFIG_LOCALVERSION rebuilds too much, for no apparent reason.

Use system_utsname for progress and debug header.
Signed-off-by: NOlaf Hering <olh@suse.de>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

Currently, we set the class bit in kernel SLB entries, and clear it on
user SLB entries.  On POWER5, ERAT entries created in real mode have
the class bit clear.  So to avoid flushing kernel ERAT entries on each
context switch, this patch inverts our usage of the class bit, setting
it on user SLB entries and clearing it on kernel SLB entries.

Booted on POWER5 and G5.
Signed-off-by: NDavid Gibson <dwg@au1.ibm.com>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

It's really not relevant for this platform in any
way, after all.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Fix build with oprofile disabled.
Signed-off-by: NAnton Blanchard <anton@samba.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

Move oprofile_model into cpu feature struct.
Signed-off-by: NAnton Blanchard <anton@samba.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

Move oprofile_impl.h into include/asm-ppc64 in preparation for moving
oprofile_model into cpu feature struct.
Signed-off-by: NAnton Blanchard <anton@samba.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

Add oprofile cpu_type to cpu feature struct.
Signed-off-by: NAnton Blanchard <anton@samba.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

Change oprofile to use num_pmcs from the cpu feature struct.
Signed-off-by: NAnton Blanchard <anton@samba.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

Remove the CPU_FTR_PMC8 feature now we encode the number of PMCs
directly.
Signed-off-by: NAnton Blanchard <anton@samba.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

Add a field in the cputable struct to store the number of PMCs.
Signed-off-by: NAnton Blanchard <anton@samba.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

I would like to be able to read the lparcfg data from any user so we
can make "intelligent" decisions based on underlying attributes when
running in lpars.  Yes there's software that likes to do this :) and
runs as non-root.

It's very similar to say VM where you can get CP to provide feedback
of the real hardware inside a VM guest.
Signed-off-by: NWim Coekaerts <wim.coekaerts@oracle.com>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

Removed PPC64 architecture specific users of asm/segment.h.
Signed-off-by: NKumar Gala <kumar.gala@freescale.com>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

Poison initmem after we free it so we catch use after free issues.
Signed-off-by: NAnton Blanchard <anton@samba.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

The following patch fixes 2 issues:
  1) use PLATFORM_LPAR bit to test if running in LPAR mode
  2) systemcfg pointer is assigned from static data in
     arch/ppc64/kernel/pacaData.c.  The file arch/ppc64/kernel/head.S
     now refers to is using the GOT binding to the pointer and hence
     must deref it.
Signed-off-by: NJimi Xenidis <jimix@watson.ibm.com>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

Consolidate the early console and PPCDBG code in udbg.c
Signed-off-by: NMilton Miller <miltonm@bga.com>
Signed-off-by: NAnton Blanchard <anton@samba.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

Trim some no longer needed includes from udbg.c and friends.
Signed-off-by: NMilton Miller <miltonm@bga.com>
Signed-off-by: NAnton Blanchard <anton@samba.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

Take udbg out of ppc_md. Allows us to not overwrite early udbg inits
when assigning ppc_md.
Signed-off-by: NMilton Miller <miltonm@bga.com>
Signed-off-by: NAnton Blanchard <anton@samba.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

Split scc and 15550 functions from udbg each into their own file.
This makes them more symetric with the lpar and btext code.
Signed-off-by: NMilton Miller <miltonm@bga.com>
Signed-off-by: NAnton Blanchard <anton@samba.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

make udbg_init_uart set the ppc_md udbg methods.
Signed-off-by: NMilton Miller <miltonm@bga.com>
Signed-off-by: NAnton Blanchard <anton@samba.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

Make the 16550 and real mode 16550 use tail recursion like the scc code
instead of repeating the routine except for the character sent.

Gcc recoginizes the tail recursion and handles it efficently without
stack allocations.  The maple real putc shrinks from 188 to 104 bytes
of instructions.  udbg_putc drops from 188 to 140 bytes.
Signed-off-by: NMilton Miller <miltonm@bga.com>
Signed-off-by: NAnton Blanchard <anton@samba.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

Now that xmon is fixed we should not need the dummy getc routines.
Signed-off-by: NMilton Miller <miltonm@bga.com>
Signed-off-by: NAnton Blanchard <anton@samba.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

udbg_getc_poll is a ppc_md function.   don't call directly into udbg.c
Signed-off-by: NMilton Miller <miltonm@bga.com>
Signed-off-by: NAnton Blanchard <anton@samba.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

Patch from Richard Purdie

This patch updates the PCMCIA pxa2xx_sharpsl driver to support multiple scoop
devices by adding a scoop to pcmcia slot mapping structure. It adds platform
support for poodle, is known to work on spitz (which is dual slot) and
should also support collie with a minor amount of further work.
Signed-off-by: NRichard Purdie <rpurdie@rpsys.net>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Patch from Ben Dooks

The n30 machine file is using a kernel thread to change the
state of the USB D+ pull-up resistor, which is not the proper
way to do this. Once the usb-gadget support for the 24xx is
merge, the proper access method will be added.
This patch also removes the problem of using HZ for the
msleep calls, from Nishanth Aravamudan.
Signed-off-by: NBen Dooks <ben-linux@fluff.org>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Use TIF bit to tell if a process is running in 31 bit mode instead of checking
the addressing mode bits of the PSW.
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

There is a race in pfault_interrupt.  That function gets called two times for
each pfault notification.  Once with a subcode of 0 to indicate that a real
page is not available and once with a subcode of 0x80 to indicate that the
page is present again.

Since the two external interrupts can be delivered on two different cpus the
order in which the two calls are made is unpredictable.  It is possible that
the subcode 0x80 interrupt is completed before the subcode 0x00 interrupt has
done the wake_up() call.

To avoid calling wake_up() on an already removed task structure proper task
structure reference counting is needed.  Increase the reference counter in the
subcode 0x00 interrupt before setting pfault_wait to zero and return the
reference after the wake_up call.
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

debug feature changes/bug fixes:

- Use get_clock() function instead of private inline assembly.

- Use 'struct timeval' instead of 'struct timespec' for call to
  tod_to_timeval().  Now the microsecond part of the timestamp is correct
  again.

- Fix a locking problem: when creating a snapshot of the current content
  of the debug areas, lock the entire debug_info object.
Signed-off-by: NMichael Holzheu <holzheu@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

The new machine check handler still has a few bugs.

1) The system entry time has to be stored in the machine check handler,

2) the machine check return psw may not be stored at the usual place
   because it might overwrite the return psw of the interrupted context,

3) the return address for the call to s390_handle_mcck in the i/o interrupt
   handler is not correct,

4) the system call cleanup has to take the different save area of the
   machine check handler into account,

5) the machine check handler may not call UPDATE_VTIME before
   CREATE_STACK_FRAME, and

6) the io leave path needs a critical section cleanup to make sure that the
   TIF_MCCK_PENDING bit is really checked before switching back to user space.
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

We were leaking pmd pages when 3_LEVEL_PGTABLES was enabled.  This fixes that.
Signed-off-by: NJeff Dike <jdike@addtoit.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

cleanup and fix the check for advanced sysemu (PTRACE_SYSEMU_SINGLESTEP
option)
Signed-off-by: NBodo Stroesser <bstroesser@fujitsu-siemens.com>
Signed-off-by: NJeff Dike <jdike@addtoit.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Add new cmdline setups:
  - noprocmm
  - noptracefaultinfo
In case of testing, they can be used to switch off usage of
/proc/mm and PTRACE_FAULTINFO independently.
Signed-off-by: NBodo Stroesser <bstroesser@fujitsu-siemens.com>
Signed-off-by: NJeff Dike <jdike@addtoit.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>