- Saving the cpu registers of all cpus before booting in to the crash
  kernel.

- crash_setup_regs will save the registers of the cpu on which panic has
  occured.  One of the concerns ppc64 folks raised is that after capturing the
  register states, one should not pop the current call frame and push new one.
   Hence it has been inlined.  More call frames later get pushed on to stack
  (machine_crash_shutdown() and machine_kexec()), but one will not want to
  backtrace those.

- Not very sure about the CFI annotations.  With this patch I am getting
  decent backtrace with gdb.  Assuming, compiler has generated enough
  debugging information for crash_kexec().  Coding crash_setup_regs() in pure
  assembly makes it tricky because then it can not be inlined and we don't
  want to return back after capturing register states we don't want to pop
  this call frame.

- Saving the non-panicing cpus registers will be done in the NMI handler
  while shooting down them in machine_crash_shutdown.

- Introducing CRASH_DUMP option in Kconfig for x86_64.
Signed-off-by: NMurali M Chakravarthy <muralim@in.ibm.com>
Signed-off-by: NVivek Goyal <vgoyal@in.ibm.com>
Cc: Andi Kleen <ak@muc.de>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

)

From: Vivek Goyal <vgoyal@in.ibm.com>

- Implementing the machine_crash_shutdown for x86_64 which will be called by
  crash_kexec (called in case of a panic, sysrq etc.).  Here we do things
  similar to i386.  Disable the interrupts, shootdown the cpus and shutdown
  LAPIC and IOAPIC.

Changes in this version:

- As the Eric's APIC initialization patches are reverted back, reintroducing
  LAPIC and IOAPIC shutdown.

- Added some comments on CPU hotplug, modified code as suggested by Andi
  kleen.
Signed-off-by: NMurali M Chakravarthy <muralim@in.ibm.com>
Signed-off-by: NVivek Goyal <vgoyal@in.ibm.com>
Cc: Andi Kleen <ak@muc.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

- elfcorehdr= specifies the location of elf core header stored by the
  crashed kernel.  This command line option will be passed by the kexec-tools
  to capture kernel.

Changes in this version :

- Added more comments in kernel-parameters.txt and in code.
Signed-off-by: NMurali M Chakravarthy <muralim@in.ibm.com>
Signed-off-by: NVivek Goyal <vgoyal@in.ibm.com>
Cc: Andi Kleen <ak@muc.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

)

From: Vivek Goyal <vgoyal@in.ibm.com>

- This patch introduces the memmap option for x86_64 similar to i386.

- memmap=exactmap enables setting of an exact E820 memory map, as specified
  by the user.

Changes in this version:

- Used e820_end_of_ram() to find the max_pfn as suggested by Andi kleen.

- removed PFN_UP & PFN_DOWN macros

- Printing the user defined map also.
Signed-off-by: NMurali M Chakravarthy <muralim@in.ibm.com>
Signed-off-by: NHariprasad Nellitheertha <nharipra@gmail.com>
Signed-off-by: NVivek Goyal <vgoyal@in.ibm.com>
Cc: Andi Kleen <ak@muc.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

)

From: Vivek Goyal <vgoyal@in.ibm.com>

crash_setup_regs() is an architecture dependent function which is called in
architecture independent section.  So every architecture supporting kexec
should at least provide a dummy definition of crash_setup_regs() even if
crash dumping is not implemented yet, to avoid build failures.
Signed-off-by: NVivek Goyal <vgoyal@in.ibm.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Fixes a compilation warning message in i386
Signed-off-by: NVivek Goyal <vgoyal@in.ibm.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

- If system panics then cpu register states are captured through funciton
  crash_get_current_regs().  This is not a inline function hence a stack frame
  is pushed on to the stack and then cpu register state is captured.  Later
  this frame is popped and new frames are pushed (machine_kexec).

- In theory this is not very right as we are capturing register states for a
  frame and that frame is no more valid.  This seems to have created back
  trace problems for ppc64.

- This patch fixes it up.  The very first thing it does after entering
  crash_kexec() is to capture the register states.  Anyway we don't want the
  back trace beyond crash_kexec().  crash_get_current_regs() has been made
  inline

- crash_setup_regs() is the top architecture dependent function which should
  be responsible for capturing the register states as well as to do some
  architecture dependent tricks.  For ex.  fixing up ss and esp for i386.
  crash_setup_regs() has also been made inline to ensure no new call frame is
  pushed onto stack.
Signed-off-by: NVivek Goyal <vgoyal@in.ibm.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Removes the call to get_cpu() and put_cpu() as it is not required.
Signed-off-by: NVivek Goyal <vgoyal@in.ibm.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

- Kexec on panic functionality allocates memory for saving cpu registers in
  case of system crash event.  Address of this allocated memory needs to be
  exported to user space, which is used by kexec-tools.

- Previously, a single /sys/kernel/crash_notes entry was being exported as
  memory allocated was a single continuous array.  Now memory allocation being
  dyanmic and per cpu based, address of per cpu buffer is exported through
  "/sys/devices/system/cpu/cpuX/crash_notes"
Signed-off-by: NVivek Goyal <vgoyal@in.ibm.com>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

- In case of system crash, current state of cpu registers is saved in memory
  in elf note format.  So far memory for storing elf notes was being allocated
  statically for NR_CPUS.

- This patch introduces dynamic allocation of memory for storing elf notes.
  It uses alloc_percpu() interface.  This should lead to better memory usage.

- Introduced based on Andi Kleen's and Eric W. Biederman's suggestions.

- This patch also moves memory allocation for elf notes from architecture
  dependent portion to architecture independent portion.  Now crash_notes is
  architecture independent.  The whole idea is that size of memory to be
  allocated per cpu (MAX_NOTE_BYTES) can be architecture dependent and
  allocation of this memory can be architecture independent.
Signed-off-by: NVivek Goyal <vgoyal@in.ibm.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

)

From: Vivek Goyal <vgoyal@in.ibm.com>

This patch fixes a minor bug based on Andi Kleen's suggestion.  asm's can't be
broken in this particular case, hence merging them.
Signed-off-by: NVivek Goyal <vgoyal@in.ibm.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Do it via Kconfig rather than via #error.
Signed-off-by: NAlexey Dobriyan <adobriyan@gmail.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

)

From: Brian Gerst <bgerst@didntduck.org>

Call sched_setscheduler() directly instead.
Signed-off-by: NBrian Gerst <bgerst@didntduck.org>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

)

From: Adrian Bunk <bunk@stusta.de>

- create one common dump_thread() prototype in kernel.h

- dump_thread() is only used in fs/binfmt_aout.c and can therefore be
  removed on all architectures where CONFIG_BINFMT_AOUT is not
  available
Signed-off-by: NAdrian Bunk <bunk@stusta.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

...
  CC [M]  drivers/char/ipmi/ipmi_msghandler.o
drivers/char/ipmi/ipmi_msghandler.c:3301: `proc_ipmi_root' undeclared here (not in a function)
drivers/char/ipmi/ipmi_msghandler.c:3301: initializer element is not constant
drivers/char/ipmi/ipmi_msghandler.c:3301: (near initialization for `__ksymtab_proc_ipmi_root.value')
drivers/char/ipmi/ipmi_msghandler.c:1535: warning: `ipmb_file_read_proc' defined but not used
drivers/char/ipmi/ipmi_msghandler.c:1551: warning: `version_file_read_proc' defined but not used
drivers/char/ipmi/ipmi_msghandler.c:1561: warning: `stat_file_read_proc' defined but not used
...
  CC [M]  drivers/char/ipmi/ipmi_poweroff.o
drivers/char/ipmi/ipmi_poweroff.c: In function `ipmi_poweroff_init':
drivers/char/ipmi/ipmi_poweroff.c:616: warning: implicit declaration of function `unregister_sysctl_table'
drivers/char/ipmi/ipmi_poweroff.c:616: `ipmi_table_header' undeclared (first use in this function)
drivers/char/ipmi/ipmi_poweroff.c:616: (Each undeclared identifier is reported only once
drivers/char/ipmi/ipmi_poweroff.c:616: for each function it appears in.)
Signed-off-by: NAdrian Bunk <bunk@stusta.de>
Cc: Corey Minyard <minyard@acm.org>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Especially useful when users have booted with 'quiet'.  In the regular 'oops'
path, we set the console_loglevel before we start spewing debug info, but we
can call the backtrace code from other places now too, such as the spinlock
debugging code.
Signed-off-by: NDave Jones <davej@redhat.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Signed-off-by: NDave Jones <davej@redhat.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Add list_for_each_entry_safe_reverse() to linux/list.h

This is needed by unmerged cachefs and be an as-yet-unreviewed
device_shutdown() fix.
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Cc: Patrick Mochel <mochel@digitalimplant.org>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

A simple driver for the CS5535 and CS5536 that allows a user-space program
to manipulate GPIO pins.  The CS5535/CS5536 chips are Geode processor
companion devices.
Signed-off-by: NBen Gardner <bgardner@wabtec.com>
Signed-off-by: NRichard Knutsson <ricknu-0@student.ltu.se>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

dev->get_wireless_stats is deprecated but removing it also removes wireless
subdirectory in sysfs. This patch puts it back.

akpm: I don't know what's happening here.  This might be appropriate as a
2.6.15.x compatibility backport.  Waiting to hear from Jeff.
Signed-off-by: NAndrey Borzenkov <arvidjaar@mail.ru>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Jeff Garzik <jgarzik@pobox.com>
Cc: <stable@kernel.org>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Recent X "nv" driver was fixed for various issues with modern 6xxx and 7xxx
cards.  This patch ports those fixes to nvidiafb.  This makes it work fine
on the 6600 bundled with the newest G5 macs.  I've verified it still works
on the 5200FX of the iMacG5.
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: N"Antonino A. Daplas" <adaplas@pol.net>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

It seems the "make UID16 support optional" patch was checked when it
edited the -tiny tree some time ago, but it wasn't checked whether it
still matches the current situation when it was submitted for inclusion
in -mm. This patch fixes the following bugs:
- ARCH_S390X does no longer exist, nowadays this has to be expressed
  through (S390 && 64BIT)
- in five architecture specific Kconfig files the UID16 options
  weren't removed

Additionally, it changes the fragile negative dependencies of UID16 to
positive dependencies (new architectures are more likely to not require
UID16 support).
Signed-off-by: NAdrian Bunk <bunk@stusta.de>
Acked-by: NMatt Mackall <mpm@selenic.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Not all architectures implement asm/serial.h, and the driver doesn't appear to
need it anyway.

Cc: Paul Fulghum <paulkf@microgate.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Russell King <rmk@arm.linux.org.uk>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Cc: Eric Dumazet <dada1@cosmosbay.com>
Cc: Paul Mackerras <paulus@samba.org>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

I think it is better to set ->next_pending in the caller, when
it is needed. This saves one parameter, and this coincides with
cpu_quiet() beahaviour, which sets ->completed = ->cur itself.
Signed-off-by: NOleg Nesterov <oleg@tv-sign.ru>
Acked-by: NPaul E. McKenney <paulmck@us.ibm.com>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

convert the block loop device from semaphores to completions.
Signed-off-by: NIngo Molnar <mingo@elte.hu>

The patch changes semaphores that are initialized as
locked to complete().

Source: MontaVista Software, Inc.
Modified-by: NSteven Rostedt <rostedt@goodmis.org>

The following patch is from Montavista.  I modified it slightly.
Semaphores are currently being used where it makes more sense for
completions.  This patch corrects that.
Signed-off-by: NAleksey Makarov <amakarov@ru.mvista.com>
Signed-off-by: NSteven Rostedt <rostedt@goodmis.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

change CPU3WDT semaphores to completions.
Signed-off-by: NIngo Molnar <mingo@elte.hu>

change SX8 semaphores to completions.
Signed-off-by: NIngo Molnar <mingo@elte.hu>

This patch converts the superblock-lock semaphore to a mutex, affecting
lock_super()/unlock_super(). Tested on ext3 and XFS.
Signed-off-by: NIngo Molnar <mingo@elte.hu>

This patch converts the inode semaphore to a mutex. I have tested it on
XFS and compiled as much as one can consider on an ia64. Anyway your
luck with it might be different.
Modified-by: NIngo Molnar <mingo@elte.hu>

(finished the conversion)
Signed-off-by: NJes Sorensen <jes@sgi.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

This patch switches XFS over to use the new mutex code directly as
opposed to the previous workaround patch I posted earlier that avoided
the namespace clash by forcing it back to semaphores. This falls in the
'works for me<tm>' category.
Signed-off-by: NJes Sorensen <jes@trained-monkey.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

more mutex debugging: check for held locks during memory freeing,
task exit, enable sysrq printouts, etc.
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NArjan van de Ven <arjan@infradead.org>

mutex implementation - add debugging code.
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NArjan van de Ven <arjan@infradead.org>

Add mutex design related documentation.
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NArjan van de Ven <arjan@infradead.org>

mutex implementation, core files: just the basic subsystem, no users of it.
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NArjan van de Ven <arjan@infradead.org>

add the per-arch mutex.h files for the remaining architectures.

We default to asm-generic/mutex-dec.h, because that performs
quite well on most arches. Arches that do not have atomic
decrement/increment instructions should switch to mutex-xchg.h
instead. Arches can also provide their own implementation for
the mutex fastpath primitives.
Signed-off-by: NArjan van de Ven <arjan@infradead.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>