As Andrew noted, my previous patch ("debug lockups: Improve lockup
detection") broke/removed SysRq-L support from architecture that do
not provide a __trigger_all_cpu_backtrace implementation.

Restore a fallback path and clean up the SysRq-L machinery a bit:

 - Rename the arch method to arch_trigger_all_cpu_backtrace()

 - Simplify the define

 - Document the method a bit - in the hope of more architectures
   adding support for it.

[ The patch touches Sparc code for the rename. ]

Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: "David S. Miller" <davem@davemloft.net>
LKML-Reference: <20090802140809.7ec4bb6b.akpm@linux-foundation.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

When debugging a recent lockup bug i found various deficiencies
in how our current lockup detection helpers work:

 - SysRq-L is not very efficient as it uses a workqueue, hence
   it cannot punch through hard lockups and cannot see through
   most soft lockups either.

 - The SysRq-L code depends on the NMI watchdog - which is off
   by default.

 - We dont print backtraces from the RCU code's built-in
   'RCU state machine is stuck' debug code. This debug
   code tends to be one of the first (and only) mechanisms
   that show that a lockup has occured.

This patch changes the code so taht we:

 - Trigger the NMI backtrace code from SysRq-L instead of using
   a workqueue (which cannot punch through hard lockups)

 - Trigger print-all-CPU-backtraces from the RCU lockup detection
   code

Also decouple the backtrace printing code from the NMI watchdog:

 - Dont use variable size cpumasks (it might not be initialized
   and they are a bit more fragile anyway)

 - Trigger an NMI immediately via an IPI, instead of waiting
   for the NMI tick to occur. This is a lot faster and can
   produce more relevant backtraces. It will also work if the
   NMI watchdog is disabled.

 - Dont print the 'dazed and confused' message when we print
   a backtrace from the NMI

 - Do a show_regs() plus a dump_stack() to get maximum info
   out of the dump. Worst-case we get two stacktraces - which
   is not a big deal. Sometimes, if register content is
   corrupted, the precise stack walker in show_regs() wont
   give us a full backtrace - in this case dump_stack() will
   do it.

Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
LKML-Reference: <new-submission>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Every so often, after code shuffles, I need to go through and unbitrot
the Lguest Journey (see drivers/lguest/README).  Since we now use RCU in
a simple form in one place I took the opportunity to expand that explanation.
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Paul McKenney <paulmck@linux.vnet.ibm.com>

I don't really notice it (except to begrudge the extra vertical
space), but Ingo does.  And he pointed out that one excuse of lguest
is as a teaching tool, it should set a good example.
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
Cc: Ingo Molnar <mingo@redhat.com>

Signed-off-by: NKumar Gala <galak@kernel.crashing.org>

General update of defconfig including the following notable changes:
 - Enable Highmem support.
 - Support for PCMCIA based daughter card.
Signed-off-by: NMartyn Welch <martyn.welch@gefanuc.com>
Signed-off-by: NKumar Gala <galak@kernel.crashing.org>

General update of defconfig including the following notable changes:
 - Enable GPIO access via sysfs on GE Fanuc's PPC9A.
 - Enable Highmem support.
 - Support for PCMCIA based daughter card.
Signed-off-by: NMartyn Welch <martyn.welch@gefanuc.com>
Signed-off-by: NKumar Gala <galak@kernel.crashing.org>

U-Boot maps PCI IO at 0xe0300000, while current dts files specify
0xe2000000. This leads to the following oops with CONFIG_8139TOO_PIO=y.

8139too Fast Ethernet driver 0.9.28
Machine check in kernel mode.
Caused by (from SRR1=41000): Transfer error ack signal
Oops: Machine check, sig: 7 [#1]
MPC837x RDB
[...]
NIP [00000900] 0x900
LR [c0439df8] rtl8139_init_board+0x238/0x524
Call Trace:
[cf831d90] [c0439dcc] rtl8139_init_board+0x20c/0x524 (unreliable)
[cf831de0] [c043a15c] rtl8139_init_one+0x78/0x65c
[cf831e40] [c0235250] pci_call_probe+0x20/0x30
[...]

This patch fixes the issue by specifying the correct PCI IO base
address.
Signed-off-by: NAnton Vorontsov <avorontsov@ru.mvista.com>
Signed-off-by: NKumar Gala <galak@kernel.crashing.org>

Sometimes (e.g. when there are no UEMs attached to a board)
fsl_pq_mdio_find_free() fails to find a spare address for a TBI PHY,
this is because get_phy_id() returns bogus 0x0000ffff values
(0xffffffff is expected), and therefore mdio bus probing fails with
the following message:

  fsl-pq_mdio: probe of e0082120.mdio failed with error -16

And obviously ethernet doesn't work after this.

This patch solves the problem by adding tbi-phy node into mdio node,
so that we won't scan for spare addresses, we'll just use a fixed one.
Signed-off-by: NAnton Vorontsov <avorontsov@ru.mvista.com>
Signed-off-by: NKumar Gala <galak@kernel.crashing.org>

Linux isn't able to detect link changes on ethernet ports that were
used by U-Boot. This is because U-Boot wrongly clears interrupt
polarity bit (INTPOL, 0x400) in the extended status register (EXT_SR,
0x1b) of Marvell PHYs.

There is no easy way for PHY drivers to know IRQ line polarity (we
could extract it from the device tree and pass it to phydevs, but
that'll be quite a lot of work), so for now just reset the PHYs to
their default states.
Signed-off-by: NAnton Vorontsov <avorontsov@ru.mvista.com>
Signed-off-by: NKumar Gala <galak@kernel.crashing.org>

In switch_mmu_context() if we call steal_context_smp() to get a context
to use we shouldn't fall through and than call steal_context_up().  Doing
so can be problematic in that the 'mm' that steal_context_up() ends up
using will not get marked dirty in the stale_map[] for other CPUs that
might have used that mm.  Thus we could end up with stale TLB entries in
the other CPUs that can cause all kinda of havoc.
Signed-off-by: NKumar Gala <galak@kernel.crashing.org>

This functionality is needed to kmap_atomic() highmem pages that may
potentially have or are about to set up other mappings with
non-standard caching attributes.
Signed-off-by: NThomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: NDave Airlie <airlied@redhat.com>

Those definitions are already provided by asm-generic
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: NPaul Mundt <lethal@linux-sh.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

mm: Pass virtual address to [__]p{te,ud,md}_free_tlb()

Upcoming paches to support the new 64-bit "BookE" powerpc architecture
will need to have the virtual address corresponding to PTE page when
freeing it, due to the way the HW table walker works.

Basically, the TLB can be loaded with "large" pages that cover the whole
virtual space (well, sort-of, half of it actually) represented by a PTE
page, and which contain an "indirect" bit indicating that this TLB entry
RPN points to an array of PTEs from which the TLB can then create direct
entries. Thus, in order to invalidate those when PTE pages are deleted,
we need the virtual address to pass to tlbilx or tlbivax instructions.

The old trick of sticking it somewhere in the PTE page struct page sucks
too much, the address is almost readily available in all call sites and
almost everybody implemets these as macros, so we may as well add the
argument everywhere. I added it to the pmd and pud variants for consistency.
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: David Howells <dhowells@redhat.com> [MN10300 & FRV]
Acked-by: NNick Piggin <npiggin@suse.de>
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com> [s390]
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Reviewed the Makefile on request by Michal and this is the resulting changes.

o Use ':=' for assignmnet so we do not re-evaluate for each use
o Use $(shell echo xxx) to remove ""
o Replaced CFLAGS_KERNEL with KBUILD_CFLAGS
  The settings are equally relevant for modules and the linked kernel
o Dropped LDFLAGS_BLOB - it is no longer used
o Refactored assignmnets to libs-y and core-y
o Use MMU for the MMU specific extension. "MMUEXT" was hurting my eyes
  and I did not wanted it spread to m68k
Signed-off-by: NSam Ravnborg <sam@ravnborg.org>
Signed-off-by: NMichal Simek <monstr@monstr.eu>

Signed-off-by: NMichal Simek <monstr@monstr.eu>

For example reiserfs use this relocation type.
Signed-off-by: NMichal Simek <monstr@monstr.eu>

New reloc type R_MICROBLAZE_32_PCREL_LO requires a null handler (no work to do).

Remove legacy hack for broken linker pre gcc-4.1.1, that required us to extract
an offset from the code, add it to the addend, then rewrite the instruction.

Fixup the invalid reloc type error output.

Boot tested with the xilinx_emaclite ethernet driver.
Signed-off-by: NJohn Williams <john.williams@petalogix.com>
Signed-off-by: NMichal Simek <monstr@monstr.eu>

The ipc system call is now unused in microblaze,
as the system call table points directly to the
indidual system calls for IPC.
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NMichal Simek <monstr@monstr.eu>

This patch add support for cases where load/store instruction
in put/get_user macro gets unaligned pointer to data and this
address is not valid. I prevent all cases which can failed.
I had to disable first stage of unaligned handler which is used
only for noMMU kernel and the whole work is done when interrupt
is enabled.
You have enable HW support for detect unaligned access in Microblaze.

This patch fixed three LTP tests:
getpeername01, getsockname01, socketpair01
Signed-off-by: NMichal Simek <monstr@monstr.eu>

Signed-off-by: NMichal Simek <monstr@monstr.eu>

Calling fixup when we are in kernel mode. This
prevent fault for copy_to/from_user. This fault
was find thanks to writev01/03/04 LTP tests.
Signed-off-by: NMichal Simek <monstr@monstr.eu>

We need to define _PAGE_FILE macro and change pte
functions. Microblaze use the same MMU as PowerPC
that's why we define _PAGE_FILE in the same style.
This change fixed remap_file_pages01 LTP test.
Signed-off-by: NMichal Simek <monstr@monstr.eu>

For 64bits arguments gcc caused that put_user macro
works with wrong value because of optimalization.
Adding volatile caused that gcc not optimized it.

It is possible to use (as Blackfin do) two put_user
macros with 32bits arguments but there is one more
instruction which is due to duplication zero return
value which is called put_user_asm macro.
Signed-off-by: NMichal Simek <monstr@monstr.eu>

It is necessary to zeroed r7 when r7 points to bad
dtb - this caused that we have correct messages
about compiled-in dtb or passing via r7
Signed-off-by: NMichal Simek <monstr@monstr.eu>

I can't clear r7 because if I do it I lose information
where DTB come from.
Signed-off-by: NMichal Simek <monstr@monstr.eu>

Print accurate message about place where FDT blob is.
Signed-off-by: NMichal Simek <monstr@monstr.eu>

If r7 is zero at kernel boot, or does not point to a valid DTB, then
we fall back to a DTB (assumed to be) linked statically in the kernel, instead
of blindly copying bogus cruft into the kernel DTB memory region
Signed-off-by: NJohn Williams <john.williams@petalogix.com>
Signed-off-by: NMichal Simek <monstr@monstr.eu>

Remove duplicated #include('s) in
  arch/microblaze/include/asm/io.h
Signed-off-by: NHuang Weiyi <weiyi.huang@gmail.com>
Signed-off-by: NMichal Simek <monstr@monstr.eu>

This fix remove bug which we had till now in all
Microblaze MMU code. Primary tested on mmap01 LTP test.
We forget to flush invalid tlb which were changed - we
used them and there were wrong old data which wasn't correct.
Signed-off-by: NMichal Simek <monstr@monstr.eu>

The combination of noexec=on and a clock_gettime call with clock id
CLOCK_THREAD_CPUTIME_ID is broken. The vdso code switches to the
access register mode to get access to the per-cpu data structure to
execute the magic ectg instruction. After the ectg instruction the
code always switches back to the primary mode but for noexec=on the
correct mode is the secondary mode. The effect of the bug is that the
user space program looses the access to all mappings without PROT_EXEC,
e.g. the stack. The problem is fixed by restoring the mode that has
been active before the switch to the access register mode.
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

vdso per cpu area allocation in smp_prepare_cpus() happens with GFP_KERNEL
but irqs disabled. Triggers this one:

Badness at kernel/lockdep.c:2280
Modules linked in:
CPU: 0 Not tainted 2.6.30 #2
Process swapper (pid: 1, task: 000000003fe88000, ksp: 000000003fe87eb8)
Krnl PSW : 0400c00180000000 0000000000083360 (lockdep_trace_alloc+0xec/0xf8)
[...]
Call Trace:
([<00000000000832b6>] lockdep_trace_alloc+0x42/0xf8)
 [<00000000000b1880>] __alloc_pages_internal+0x3e8/0x5c4
 [<00000000000b1b4a>] __get_free_pages+0x3a/0xb0
 [<0000000000026546>] vdso_alloc_per_cpu+0x6a/0x18c
 [<00000000005eff82>] smp_prepare_cpus+0x322/0x594
 [<00000000005e8232>] kernel_init+0x76/0x398
 [<000000000001bb1e>] kernel_thread_starter+0x6/0xc
 [<000000000001bb18>] kernel_thread_starter+0x0/0xc

Fix this by moving the allocation out of the irqs disabled section.
Reported-by: NChristian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

swsusp_arch_suspend() actually saves all cpu register contents on
hibernation.
Machine checks must be disabled since swsusp_arch_suspend() stores
register contents to their lowcore save areas. That's the same
place where register contents on machine checks would be saved.
To avoid register corruption disable machine checks.
We must also disable machine checks in the new psw mask for
program checks, since swsusp_arch_suspend() may generate program
checks.
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Our swsusp_arch_suspend() backend implementation disables prefixing
by setting the contents of the prefix register to 0.
However afterwards common code functions are called which might
access percpu data structures.
Since the lowcore contains e.g. the percpu base pointer this isn't
a good idea. So fix this by copying the hibernating cpu's lowcore to
absolute address zero.
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Timer interrupts are excluded from being disabled during suspend. The
clock events code manages the disabling of clock events on its own
because the timer interrupt needs to be functional before the resume
code reenables the device interrupts.

The mfgpt timer request its interrupt without setting the IRQF_TIMER
flag so suspend_device_irqs() disables it as well which results in a
fatal resume failure.

Adding IRQF_TIMER to the interupt flags when requesting the mrgpt
timer interrupt solves the problem.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
LKML-Reference: <new-submission>
Cc: Andres Salomon <dilinger@debian.org>
Cc: stable@kernel.org

This patch for at_hdmac adds the slave transfers capability to the Atmel DMA
controller available on some AT91 SOCs. This allow peripheral to memory and
memory to peripheral transfers with hardware handshaking.

Slave structure for controller specific information is passed through channel
private data. This at_dma_slave structure is defined in at_hdmac.h header file
and relative hardware definition are moved to this file from at_hdmac_regs.h.
Doing this we allow the channel configuration from platform definition code.

This work is intensively based on dw_dmac and several slave implementations.
Signed-off-by: NNicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: NDan Williams <dan.j.williams@intel.com>

This AHB DMA Controller (aka HDMA or DMAC on AT91 systems) is availlable on
at91sam9rl chip. It will be used on other products in the future.

This first release covers only the memory-to-memory tranfer type. This is the
only tranfer type supported by this chip.  On other products, it will be used
also for peripheral DMA transfer (slave API support to come).

I used dmatest client without problem in different configurations to test it.

Full documentation for this controller can be found in the SAM9RL datasheet:
http://www.atmel.com/dyn/products/product_card.asp?part_id=4243Signed-off-by: NNicolas Ferre <nicolas.ferre@atmel.com>
Acked-by: NMaciej Sosnowski <maciej.sosnowski@intel.com>
Signed-off-by: NDan Williams <dan.j.williams@intel.com>

If we've logically disabled apics, don't probe the PCI space for the
AMD extended APIC ID.

[ Impact: prevent boot crash under Xen. ]
Signed-off-by: NJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Reported-by: NBastian Blank <bastian@waldi.eu.org>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

Fix a gcc unused variables warning.
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>

CONFIG_X86_THRESHOLD used in arch/x86/kernel/irqinit.c is always
undefined.  Rename it to the correct name "CONFIG_X86_MCE_THRESHOLD".
Signed-off-by: NHidehiro Kawai <hidehiro.kawai.ez@hitachi.com>
Reviewed-by: NHidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Cc: Andi Kleen <andi@firstfloor.org>
LKML-Reference: <4A667FD4.3010509@hitachi.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>