Replace possibly damaging broadcast writes into the per-port SP_MODE
registers with individual writes for each port.  This will preserve
individual port configurations in case if ports are configured
differently.
Signed-off-by: NAlexandre Bounine <alexandre.bounine@idt.com>
Cc: Kumar Gala <galak@kernel.crashing.org>
Cc: Matt Porter <mporter@kernel.crashing.org>
Cc: Li Yang <leoli@freescale.com>
Cc: Thomas Moll <thomas.moll@sysgo.com>
Cc: Micha Nelissen <micha@neli.hopto.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Replace hardcoded maximum port number with actual reported number of
switch ports.
Signed-off-by: NAlexandre Bounine <alexandre.bounine@idt.com>
Cc: Kumar Gala <galak@kernel.crashing.org>
Cc: Matt Porter <mporter@kernel.crashing.org>
Cc: Li Yang <leoli@freescale.com>
Cc: Thomas Moll <thomas.moll@sysgo.com>
Cc: Micha Nelissen <micha@neli.hopto.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

RapidIO spec v.2.1 adds Idle Sequence 2 into LP-Serial Physical Layer.
The fix ensures that corresponding bits are not corrupted during error
handling.
Signed-off-by: NAlexandre Bounine <alexandre.bounine@idt.com>
Cc: Thomas Moll <thomas.moll@sysgo.com>
Cc: Matt Porter <mporter@kernel.crashing.org>
Cc: Li Yang <leoli@freescale.com>
Cc: Kumar Gala <galak@kernel.crashing.org>
Cc: Micha Nelissen <micha@neli.hopto.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Detects RIO link to the already enumerated device and properly sets links
between device objects.  Changes to the enumeration/discovery logic:

1. Use Master Enable bit to signal end of the enumeration - agents may
   start their discovery process as soon as they see this bit set
   (Component Tag register was used before for this purpose).

2. Enumerator sets Component Tag (!= 0) immediately during device
   setup.  This allows to identify the device if the redundant route
   exists in a RIO system.
Signed-off-by: NAlexandre Bounine <alexandre.bounine@idt.com>
Cc: Thomas Moll <thomas.moll@sysgo.com>
Cc: Matt Porter <mporter@kernel.crashing.org>
Cc: Li Yang <leoli@freescale.com>
Cc: Kumar Gala <galak@kernel.crashing.org>
Cc: Micha Nelissen <micha@neli.hopto.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Add the RIO switch driver and definitions for IDT CPS-1848 and CPS-1616
Gen2 devices.
Signed-off-by: NAlexandre Bounine <alexandre.bounine@idt.com>
Cc: Thomas Moll <thomas.moll@sysgo.com>
Cc: Matt Porter <mporter@kernel.crashing.org>
Cc: Li Yang <leoli@freescale.com>
Cc: Kumar Gala <galak@kernel.crashing.org>
Cc: Micha Nelissen <micha@neli.hopto.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Add explicit device access check before performing device enumeration.
This gives a chance to clear possible link error conditions by issuing
safe maintenance read request(s).
Signed-off-by: NAlexandre Bounine <alexandre.bounine@idt.com>
Cc: Thomas Moll <thomas.moll@sysgo.com>
Cc: Matt Porter <mporter@kernel.crashing.org>
Cc: Li Yang <leoli@freescale.com>
Cc: Kumar Gala <galak@kernel.crashing.org>
Cc: Micha Nelissen <micha@neli.hopto.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Add check for access to port-write (PW) message source device before
processing the PW message.  If source RIO device is not available (power
down or RIO link failure) trace back to a last available switch/port on
the PW message route and service failure at that point.
Signed-off-by: NAlexandre Bounine <alexandre.bounine@idt.com>
Cc: Thomas Moll <thomas.moll@sysgo.com>
Cc: Matt Porter <mporter@kernel.crashing.org>
Cc: Li Yang <leoli@freescale.com>
Cc: Kumar Gala <galak@kernel.crashing.org>
Cc: Micha Nelissen <micha@neli.hopto.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

1. Change to create attribute "routes" only for switches.

2. Add a switch-specific callback to create/remove proprietary attributes.
Signed-off-by: NAlexandre Bounine <alexandre.bounine@idt.com>
Cc: Thomas Moll <thomas.moll@sysgo.com>
Cc: Matt Porter <mporter@kernel.crashing.org>
Cc: Li Yang <leoli@freescale.com>
Cc: Kumar Gala <galak@kernel.crashing.org>
Cc: Micha Nelissen <micha@neli.hopto.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The default error-stopped state handler provides recovery mechanism as
defined by RIO specification.
Signed-off-by: NAlexandre Bounine <alexandre.bounine@idt.com>
Cc: Thomas Moll <thomas.moll@sysgo.com>
Cc: Matt Porter <mporter@kernel.crashing.org>
Cc: Li Yang <leoli@freescale.com>
Cc: Kumar Gala <galak@kernel.crashing.org>
Cc: Micha Nelissen <micha@neli.hopto.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Create back and forward links between RIO devices.  These links are
intended for use by error management and hot-plug extensions.  Links for
redundant RIO connections between switches are not set (will be fixed in a
separate patch).
Signed-off-by: NAlexandre Bounine <alexandre.bounine@idt.com>
Cc: Thomas Moll <thomas.moll@sysgo.com>
Cc: Matt Porter <mporter@kernel.crashing.org>
Cc: Li Yang <leoli@freescale.com>
Cc: Kumar Gala <galak@kernel.crashing.org>
Cc: Micha Nelissen <micha@neli.hopto.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The switch port information is obtained and stored during RIO device
setup.  Therefore repeated reads from Switch Port Information CAR may be
removed.
Signed-off-by: NAlexandre Bounine <alexandre.bounine@idt.com>
Cc: Thomas Moll <thomas.moll@sysgo.com>
Cc: Matt Porter <mporter@kernel.crashing.org>
Cc: Li Yang <leoli@freescale.com>
Cc: Kumar Gala <galak@kernel.crashing.org>
Cc: Micha Nelissen <micha@neli.hopto.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

- Rearrange RIO port-write interrupt handling to perform message
  buffering as soon as possible.

- Modify to disable port-write controller when clearing Transaction
  Error (TE) bit.
Signed-off-by: NAlexandre Bounine <alexandre.bounine@idt.com>
Cc: Thomas Moll <thomas.moll@sysgo.com>
Cc: Matt Porter <mporter@kernel.crashing.org>
Cc: Li Yang <leoli@freescale.com>
Cc: Kumar Gala <galak@kernel.crashing.org>
Cc: Micha Nelissen <micha@neli.hopto.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This set of RapidIO patches extends support for standard error recovery
mechanism and adds new IDT Gen2 sRIO switch devices - CPS-1848 and
CPS-1616.  Implementation of the standard error-stopped state recovery
mechanism (as defined by the RapidIO specification) is required for the
new switches.

Version 2 of this set of patches addresses received comments and fixes an
error notification setup issue found in the idt_gen2.c after the first
version was released.

This patch:

Make RapidIO devices appear in /sys/devices/rapidio directory instead of
top of /sys/devices directory.
Signed-off-by: NAlexandre Bounine <alexandre.bounine@idt.com>
Cc: Thomas Moll <thomas.moll@sysgo.com>
Cc: Matt Porter <mporter@kernel.crashing.org>
Cc: Li Yang <leoli@freescale.com>
Cc: Kumar Gala <galak@kernel.crashing.org>
Cc: Micha Nelissen <micha@neli.hopto.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Both mxser_disable_must_enchance_mode() and mxser_get_must_hardware_id()
called from function CheckIsMoxaMust(), when CONFIG_PCI=y.  So mark both
the functions under CONFIG_PCI.

We were warned by the following warning.

drivers/char/mxser.c:306: warning: `mxser_disable_must_enchance_mode' defined but not used
drivers/char/mxser.c:391: warning: `mxser_get_must_hardware_id'
defined but not used
Signed-off-by: NRakib Mullick <rakib.mullick@gmail.com>
Cc: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Changed <module>-objs to <module>-y in Makefile.
Signed-off-by: NTracey Dent <tdent48227@gmail.com>
Cc: Jiri Slaby <jirislaby@gmail.com>
Cc: Michal Marek <mmarek@suse.cz>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Changed <module>-objs to <module>-y in Makefile.
Signed-off-by: NTracey Dent <tdent48227@gmail.com>
Cc: Jiri Slaby <jirislaby@gmail.com>
Cc: Michal Marek <mmarek@suse.cz>
Acked-by: NJiri Kosina <jkosina@suse.cz>
Acked-by: NDavid Sterba <dsterba@suse.cz>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Changed <module>-objs to <module>-y in Makefile and use
ccflags-y option.
Signed-off-by: NTracey Dent <tdent48227@gmail.com>
Cc: Jiri Slaby <jirislaby@gmail.com>
Cc: Michal Marek <mmarek@suse.cz>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Changed <module>-objs to <module>-y in Makefile.
Signed-off-by: NTracey Dent <tdent48227@gmail.com>
Cc: Jiri Slaby <jirislaby@gmail.com>
Cc: Michal Marek <mmarek@suse.cz>
Cc: Corey Minyard <minyard@acm.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Changed <module>-objs to <module>-y in Makefile.
Signed-off-by: NTracey Dent <tdent48227@gmail.com>
Cc: Jiri Slaby <jirislaby@gmail.com>
Cc: Michal Marek <mmarek@suse.cz>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Add support for extended byte synchronous mode feature of hardware.
Signed-off-by: NPaul Fulghum <paulkf@microgate.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Structures tmp_params and new_line are copied to userland with some
padding fields unitialized.  It leads to leaking of stack memory.
Signed-off-by: NVasiliy Kulikov <segooon@gmail.com>
Acked-by: NPaul Fulghum <paulkf@microgate.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Structure par_timeout is copied to userland with some padding fields
unitialized.  Field tv_usec has type __kernel_suseconds_t, it differs from
tv_sec's type on some architectures.  It leads to leaking of stack memory.
Signed-off-by: NVasiliy Kulikov <segooon@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Structure st_loc is copied to userland with some fields unitialized.  It
leads to leaking of stack memory.
Signed-off-by: NVasiliy Kulikov <segooon@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Fix a long standing bug with per device locking.

Each device has an associated spinlock for synchronizing access to
hardware and state information with the ISR.  A single hardware card has
one or more devices.

Bug: Non ISR code correctly acquires and releases the per device lock.
ISR incorrectly always acquires and releases the lock of the first device
on the card.

The decoupled and list based nature of the ISR and deferred processing
interaction allowed this to work in normal operation.  Exceptional events
like an application forcing hardware shutdown, reset, or reconfiguration
while active can trigger the bug.

Fixed ISR to acquire and release the per device lock.

One exception is manipulation of the GPIO card resource which is global
and effectively owned by the first device of the card.  Non-ISR access to
GPIO resource is changed to use lock of first device on card.
Signed-off-by: NPaul Fulghum <paulkf@microgate.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This patch for SGI Altix/IA64 eliminates interval long timer holdoffs in
cases where we don't start an interval timer before the expiration time.
This sometimes happens when a number of interval timers on the same shub
with the same interval run simultaneously.
Signed-off-by: NDimitri Sivanich <sivanich@sgi.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This doesn't do anything.

Cc: Timur Tabi <timur@freescale.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Amit Shah <amit.shah@redhat.com>
Cc: Greg Kroah-Hartman <gregkh@suse.de>
Cc: Kumar Gala <galak@gate.crashing.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

There was a release_region() missing on the error path.
Signed-off-by: NDan Carpenter <error27@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

__init and __exit belong after the return type on functions, not
before.
Signed-off-by: NCorey Minyard <cminyard@mvista.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This takes care of leaking uninitialized kernel stack memory to
userspace from non-zeroed fields in structs in compat ipc functions.
Signed-off-by: NDan Rosenberg <drosenberg@vsecurity.com>
Cc: Manfred Spraul <manfred@colorfullife.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: <stable@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The kernel currently provides no functionality to analyze the RSS and swap
space usage of each individual sysvipc shared memory segment.

This patch adds this info for each existing shm segment by extending the
output of /proc/sysvipc/shm by two columns for RSS and swap.

Since shmctl(SHM_INFO) already provides a similiar calculation (it
currently sums up all RSS/swap info for all segments), I did split out a
static function which is now used by the /proc/sysvipc/shm output and
shmctl(SHM_INFO).

SAP products (esp.  the SAP Netweaver ABAP Kernel) uses lots of big shared
memory segments (we often have Linux systems with >= 16GB shm usage).
Sometimes we get customer reports about "slow" system responses and while
looking into their configurations we often find massive swapping activity
on the system.  With this patch it's now easy to see from the command line
if and which shm segments gets swapped out (and how much) and can more
easily give recommendations for system tuning.  Without the patch it's
currently not possible to do such shm analysis at all.

Also...

Add some spaces in front of the "size" field for 64bit kernels to get the
columns correct if you cat the contents of the file.  In
sysvipc_shm_proc_show() the kernel prints the size value in "SPEC_SIZE"
format, which is defined like this:

#if BITS_PER_LONG <= 32
#define SIZE_SPEC "%10lu"
#else
#define SIZE_SPEC "%21lu"
#endif

So, if the header is not adjusted, the columns are not correctly aligned.
I actually tested this on 32- and 64-bit and it seems correct now.
Signed-off-by: NHelge Deller <deller@gmx.de>
Cc: Manfred Spraul <manfred@colorfullife.com>
Acked-by: NHugh Dickins <hughd@google.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Presently do_execve() turns PF_KTHREAD off before search_binary_handler().
 THis has a theorical risk of PF_KTHREAD getting lost.  We don't have to
turn PF_KTHREAD off in the ENOEXEC case.

This patch moves this flag modification to after the finding of the
executable file.

This is only a theorical issue because kthreads do not call do_execve()
directly.  But fixing would be better.
Signed-off-by: NKOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Acked-by: NRoland McGrath <roland@redhat.com>
Acked-by: NOleg Nesterov <oleg@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

In /proc/stat, the number of per-IRQ event is shown by making a sum each
irq's events on all cpus.  But we can make use of kstat_irqs().

kstat_irqs() do the same calculation, If !CONFIG_GENERIC_HARDIRQ,
it's not a big cost. (Both of the number of cpus and irqs are small.)

If a system is very big and CONFIG_GENERIC_HARDIRQ, it does

	for_each_irq()
		for_each_cpu()
			- look up a radix tree
			- read desc->irq_stat[cpu]
This seems not efficient. This patch adds kstat_irqs() for
CONFIG_GENRIC_HARDIRQ and change the calculation as

	for_each_irq()
		look up radix tree
		for_each_cpu()
			- read desc->irq_stat[cpu]

This reduces cost.

A test on (4096cpusp, 256 nodes, 4592 irqs) host (by Jack Steiner)

%time cat /proc/stat > /dev/null

Before Patch:	 2.459 sec
After Patch :	  .561 sec

[akpm@linux-foundation.org: unexport kstat_irqs, coding-style tweaks]
[akpm@linux-foundation.org: fix unused variable 'per_irq_sum']
Signed-off-by: NKAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Tested-by: NJack Steiner <steiner@sgi.com>
Acked-by: NJack Steiner <steiner@sgi.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

/proc/stat shows the total number of all interrupts to each cpu.  But when
the number of IRQs are very large, it take very long time and 'cat
/proc/stat' takes more than 10 secs.  This is because sum of all irq
events are counted when /proc/stat is read.  This patch adds "sum of all
irq" counter percpu and reduce read costs.

The cost of reading /proc/stat is important because it's used by major
applications as 'top', 'ps', 'w', etc....

A test on a mechin (4096cpu, 256 nodes, 4592 irqs) shows

 %time cat /proc/stat > /dev/null
 Before Patch:  12.627 sec
 After  Patch:  2.459 sec
Signed-off-by: NKAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Tested-by: NJack Steiner <steiner@sgi.com>
Acked-by: NJack Steiner <steiner@sgi.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The length of the BLOCK_IPOLL string is making i's value be printed too
far to the right.  This patch fixes this and makes the output a bit
neater.

Currently:
                CPU0
      HI:          0
   TIMER:     599792
  NET_TX:          2
  NET_RX:          6
   BLOCK:      80807
BLOCK_IOPOLL:          0
 TASKLET:      20012
   SCHED:          0
 HRTIMER:         63
     RCU:     619279

With patch:
                    CPU0
          HI:          0
       TIMER:     585582
      NET_TX:          2
      NET_RX:          6
       BLOCK:      80320
BLOCK_IOPOLL:          0
     TASKLET:      19287
       SCHED:          0
     HRTIMER:         62
         RCU:     604441
Signed-off-by: NDavidlohr Bueso <dave@gnu.org>
Acked-by: NKeika Kobayashi <kobayashi.kk@ncos.nec.co.jp>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Document /proc/pid/pagemap in Documentation/filesystems/proc.txt
Signed-off-by: NNikanth Karthikesan <knikanth@suse.de>
Cc: Richard Guenther <rguenther@suse.de>
Cc: Balbir Singh <balbir@linux.vnet.ibm.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Acked-by: NMatt Mackall <mpm@selenic.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Export the number of anonymous pages in a mapping via smaps.

Even the private pages in a mapping backed by a file, would be marked as
anonymous, when they are modified. Export this information to user-space via
smaps.

Exporting this count will help gdb to make a better decision on which
areas need to be dumped in its coredump; and should be useful to others
studying the memory usage of a process.
Signed-off-by: NNikanth Karthikesan <knikanth@suse.de>
Acked-by: NHugh Dickins <hughd@google.com>
Reviewed-by: NKOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Matt Mackall <mpm@selenic.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

find_new_reaper() releases and regrabs tasklist_lock but was missing
proper annotations.  Add it.  This remove following sparse warning:

 warning: context imbalance in 'find_new_reaper' - unexpected unlock
Signed-off-by: NNamhyung Kim <namhyung@gmail.com>
Acked-by: NRoland McGrath <roland@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The userland ELF tools have been coping with partial-segments core files
for a few years now.  Multiple distro builds are now setting this option.
It behooves everyone who ever deals with core files to have more info
dumped in there, especially as more and more people's compilers are
producing build IDs.  Make it the default.

Anyone using older tools confused by these core files can configure this
option off, or just change /proc/PID/coredump_filter after boot.
Signed-off-by: NRoland McGrath <roland@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

We met a parameter truncated issue, consider following:
> echo "|/root/core_pattern_pipe_test %p /usr/libexec/blah-blah-blah \
%s %c %p %u %g 11 12345678901234567890123456789012345678 %t" > \
/proc/sys/kernel/core_pattern

This is okay because the strings is less than CORENAME_MAX_SIZE.  "cat
/proc/sys/kernel/core_pattern" shows the whole string.  but after we run
core_pattern_pipe_test in man page, we found last parameter was truncated
like below:

        argc[10]=<12807486>

The root cause is core_pattern allows % specifiers, which need to be
replaced during parse time, but the replace may expand the strings to
larger than CORENAME_MAX_SIZE.  So if the last parameter is % specifiers,
the replace code is using snprintf(out_ptr, out_end - out_ptr, ...), this
will write out of corename array.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: NXiaotian Feng <dfeng@redhat.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Reviewed-by: NNeil Horman <nhorman@tuxdriver.com>
Cc: Roland McGrath <roland@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Oleg Nesterov pointed out we have to prevent multiple-threads-inside-exec
itself and we can reuse ->cred_guard_mutex for it.  Yes, concurrent
execve() has no worth.

Let's move ->cred_guard_mutex from task_struct to signal_struct.  It
naturally prevent multiple-threads-inside-exec.
Signed-off-by: NKOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Reviewed-by: NOleg Nesterov <oleg@redhat.com>
Acked-by: NRoland McGrath <roland@redhat.com>
Acked-by: NDavid Howells <dhowells@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>