locale-gen on Debian showed a strange problem on parisc:
mmap2(NULL, 536870912, PROT_NONE, MAP_SHARED, 3, 0) = 0x42a54000
mmap2(0x42a54000, 103860, PROT_READ|PROT_WRITE, MAP_SHARED|MAP_FIXED, 3, 0) = -1 EINVAL (Invalid argument)

Basically it was just trying to re-mmap() a file at the same address
which it was given by a previous mmap() call. But this remapping failed
with EINVAL.

The problem is, that when MAP_FIXED and MAP_SHARED flags were used, we didn't
included the mapping-based offset when we verified the alignment of the given
fixed address against the offset which we calculated it in the previous call.
Signed-off-by: NHelge Deller <deller@gmx.de>
Cc: <stable@vger.kernel.org> # 3.10+

Use more appropriate NUMA_NO_NODE instead of -1 in all archs' module_alloc()
Signed-off-by: NJianguo Wu <wujianguo@huawei.com>
Acked-by: NDavid Rientjes <rientjes@google.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

In case we fail to power up other CPUs in a SMP system, the kernel
currently shows a wrong number of online CPUs. This change makes the
output more verbose on how many of the CPUs are online. Example:

CPU(s): 1 out of 2 PA8800 (Mako) at 900.000000 MHz online.
Signed-off-by: NHelge Deller <deller@gmx.de>

The number of IPI calls is already visible as per-cpu IPI irq counters
in/proc/cpuinfo, so let's drop this additional counting.

This partly reverts:
cd85d551 parisc: more irq statistics in /proc/interrupts
Signed-off-by: NHelge Deller <deller@gmx.de>

Implement missing functions for parisc to provide kernel audit feature.
Signed-off-by: NHelge Deller <deller@gmx.de>

Provide a macro ASM_EXCEPTIONTABLE_ENTRY() to create exception table
entries and convert all open-coded places to use that macro.

This patch is a first step toward creating a exception table which only
holds 32bit pointers even on a 64bit kernel. That way in my own kernel
I was able to reduce the in-kernel exception table from 44kB to 22kB.
Signed-off-by: NHelge Deller <deller@gmx.de>

Since the beginning of the parisc-linux port, sometimes 64bit SMP kernels were
not able to bring up other CPUs than the monarch CPU and instead crashed the
kernel.  The reason was unclear, esp. since it involved various machines (e.g.
J5600, J6750 and SuperDome). Testing showed, that those crashes didn't happened
when less than 4GB were installed, or if a 32bit Linux kernel was booted.

In the end, the fix for those SMP problems is trivial:
During the early phase of the initialization of the CPUs, including the monarch
CPU, the PDC_PSW firmware function to enable WIDE (=64bit) mode is called.
It's documented that this firmware function may clobber various registers, and
one one of those possibly clobbered registers is %cr30 which holds the task
thread info pointer.

Now, if %cr30 would always have been clobbered, then this bug would have been
detected much earlier. But lots of testing finally showed, that - at least for
%cr30 - on some machines only the upper 32bits of the 64bit register suddenly
turned zero after the firmware call.

So, after finding the root cause, the explanation for the various crashes
became clear:
- On 32bit SMP Linux kernels all upper 32bit were zero, so we didn't faced this
  problem.
- Monarch CPUs in 64bit mode always booted sucessfully, because the inital task
  thread info pointer was below 4GB.
- Secondary CPUs booted sucessfully on machines with less than 4GB RAM because
  the upper 32bit were zero anyay.
- Secondary CPus failed to boot if we had more than 4GB RAM and the task thread
  info pointer was located above the 4GB boundary.

Finally, the patch to fix this problem is trivial by saving the %cr30 register
before the firmware call and restoring it afterwards.
Signed-off-by: NHelge Deller <deller@gmx.de>
Signed-off-by: NJohn David Anglin <dave.anglin@bell.net>
Cc: <stable@vger.kernel.org> # 2.6.12+
Signed-off-by: NHelge Deller <deller@gmx.de>

This reverts commit 320c90be.

Christoph Hellwig <hch@infradead.org> commented:
This one shouldn't go in - Geert sent it a bit prematurely, as Lustre
shouldn't use it just to reimplement core VM functionality (which it
shouldn't use either, but that's a separate story).
Signed-off-by: NHelge Deller <deller@gmx.de>

Running an "echo t > /proc/sysrq-trigger" crashes the parisc kernel.  The
problem is, that in print_worker_info() we try to read the workqueue info via
the probe_kernel_read() functions which use pagefault_disable() to avoid
crashes like this:
    probe_kernel_read(&pwq, &worker->current_pwq, sizeof(pwq));
    probe_kernel_read(&wq, &pwq->wq, sizeof(wq));
    probe_kernel_read(name, wq->name, sizeof(name) - 1);

The problem here is, that the first probe_kernel_read(&pwq) might return zero
in pwq and as such the following probe_kernel_reads() try to access contents of
the page zero which is read protected and generate a kernel segfault.

With this patch we fix the interruption handler to call parisc_terminate()
directly only if pagefault_disable() was not called (in which case
preempt_count()==0).  Otherwise we hand over to the pagefault handler which
will try to look up the faulting address in the fixup tables.
Signed-off-by: NHelge Deller <deller@gmx.de>
Cc: <stable@vger.kernel.org> # v3.0+
Signed-off-by: NJohn David Anglin  <dave.anglin@bell.net>
Signed-off-by: NHelge Deller <deller@gmx.de>

Signed-off-by: NHelge Deller <deller@gmx.de>

Commit 9a46ad6d "smp: make smp_call_function_many() use logic
similar to smp_call_function_single()" has unified the way to handle
single and multiple cross-CPU function calls. Now only one interrupt
is needed for architecture specific code to support generic SMP function
call interfaces, so kill the redundant single function call interrupt.
Signed-off-by: NJiang Liu <jiang.liu@huawei.com>
Cc: Jiang Liu <liuj97@gmail.com>
Signed-off-by: NHelge Deller <deller@gmx.de>

ERROR: "flush_cache_page" [drivers/staging/lustre/lustre/libcfs/libcfs.ko] undefined!
Signed-off-by: NGeert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: NHelge Deller <deller@gmx.de>

All arch overriden implementations of do_softirq() share the following
common code: disable irqs (to avoid races with the pending check),
check if there are softirqs pending, then execute __do_softirq() on
a specific stack.

Consolidate the common parts such that archs only worry about the
stack switch.
Acked-by: NLinus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@au1.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul Mackerras <paulus@au1.ibm.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: James E.J. Bottomley <jejb@parisc-linux.org>
Cc: Helge Deller <deller@gmx.de>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Andrew Morton <akpm@linux-foundation.org>

Using 0x%# emits 0x0x.  Only one is necessary.
Signed-off-by: NJoe Perches <joe@perches.com>
Acked-by: NTakashi Iwai <tiwai@suse.de>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

We can't use dev->mod_index for selecting the interrupt routing entry,
because it's not an index into interrupt routing table. It will be even
wrong on a machine with 2 CPUs (4 cores). But all needed information is
contained in the PAT entries for the serial ports. mod[0] contains the
iosapic address and mod_info has some indications for the interrupt
input (at least it looks like it). This patch implements the searching
for the right iosapic and uses this interrupt input information.
Signed-off-by: NThomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: <stable@vger.kernel.org> # 3.10
Signed-off-by: NHelge Deller <deller@gmx.de>

The KERNEL_SYSCALL define is not used anymore so the header can be
removed.
Signed-off-by: NJohn David Anglin <dave.anglin@bell.net>
Signed-off-by: NHelge Deller <deller@gmx.de>

The parisc architecture does not have a pte special bit. As a result,
special mappings are handled with the VM_PFNMAP and VM_MIXEDMAP flags.
VM_MIXEDMAP mappings may or may not have a "struct page" backing. When
pfn_valid() is false, there is no "struct page" backing. Otherwise, they
are treated as normal pages.

The FireGL driver uses the VM_MIXEDMAP without a backing "struct page".
This treatment caused a panic due to a TLB data miss in
update_mmu_cache. This appeared to be in the code generated for
page_address(). We were in fact using a very circular bit of code to
determine the physical address of the PFN in various cache routines.
This wasn't valid when there was no "struct page" backing.  The needed
address can in fact be determined simply from the PFN itself without
using the "struct page".

The attached patch updates update_mmu_cache(), flush_cache_mm(),
flush_cache_range() and flush_cache_page() to check pfn_valid() and to
directly compute the PFN physical and virtual addresses.
Signed-off-by: NJohn David Anglin <dave.anglin@bell.net>
Cc: <stable@vger.kernel.org> # 3.10
Signed-off-by: NHelge Deller <deller@gmx.de>

The __cpuinit type of throwaway sections might have made sense
some time ago when RAM was more constrained, but now the savings
do not offset the cost and complications.  For example, the fix in
commit 5e427ec2 ("x86: Fix bit corruption at CPU resume time")
is a good example of the nasty type of bugs that can be created
with improper use of the various __init prefixes.

After a discussion on LKML[1] it was decided that cpuinit should go
the way of devinit and be phased out.  Once all the users are gone,
we can then finally remove the macros themselves from linux/init.h.

This removes all the parisc uses of the __cpuinit macros.

[1] https://lkml.org/lkml/2013/5/20/589Acked-by: NJames Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Helge Deller <deller@gmx.de>
Cc: linux-parisc@vger.kernel.org
Signed-off-by: NPaul Gortmaker <paul.gortmaker@windriver.com>

I still see the occasional random segv on rp3440.  Looking at one of
these (a code 15), it appeared the problem must be with the cache
handling of anonymous pages.  Reviewing this, I noticed that the space
register %sr1 might be being clobbered when we flush an anonymous page.

Register %sr1 is used for TLB purges in a couple of places.  These
purges are needed on PA8800 and PA8900 processors to ensure cache
consistency of flushed cache lines.

The solution here is simply to move the %sr1 load into the TLB lock
region needed to ensure that one purge executes at a time on SMP
systems.  This was already the case for one use.  After a few days of
operation, I haven't had a random segv on my rp3440.
Signed-off-by: NJohn David Anglin <dave.anglin@bell.net>
Cc: <stable@vger.kernel.org> # 3.10
Signed-off-by: NHelge Deller <deller@gmx.de>

Signed-off-by: NHelge Deller <deller@gmx.de>
Cc: <stable@vger.kernel.org> # 3.10

parisc: Use unshadowed index register for flush instructions in flush_dcache_page_asm and flush_icache_page_asm

The comment at the start of pacache.S states that the base and index
registers used for fdc,fic, and pdc instructions should not use shadowed
registers. Although this is probably unnecessary for tmpalias flushes,
there is also no reason not to comply.
Signed-off-by: NJohn David Anglin <dave.anglin@bell.net>
Signed-off-by: NHelge Deller <deller@gmx.de>

pci_mmap_page_range() is needed for X11-server support on C8000 with ATI
FireGL card.

Signed-off-by Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: NHelge Deller <deller@gmx.de>

The C8000 workstation (64 bit kernel only) has a somewhat different
serial port configuration than other models.
Thomas Bogendoerfer sent a patch to fix this in September 2010, which
was now minimally modified by me.
Signed-off-by: NThomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: NHelge Deller <deller@gmx.de>

'boot_args' is an input args, and 'boot_command_line' has a fix length.
So use strlcpy() instead of strcpy() to avoid memory overflow.
Signed-off-by: NChen Gang <gang.chen@asianux.com>
Acked-by: NKyle McMartin <kyle@mcmartin.ca>
Signed-off-by: NHelge Deller <deller@gmx.de>

'path.bc[i]' can be asigned by PCI_SLOT() which can '> 10', so sizeof(6
* "%u:" + "%u" + '\0') may be 21.

Since 'name' length is 20, it may be memory overflow.

And 'path.bc[i]' is 'unsigned char' for printing, we can be sure the
max length of 'name' must be less than 28.

So simplify thinking, we can use 28 instead of 20 directly, and do not
think of whether 'patchc.bc[i]' can '> 100'.
Signed-off-by: NChen Gang <gang.chen@asianux.com>
Signed-off-by: NHelge Deller <deller@gmx.de>

The logic to detect if the irq stack was already in use with
raw_spin_trylock() is wrong, because it will generate a "trylock failure
on UP" error message with CONFIG_SMP=n and CONFIG_DEBUG_SPINLOCK=y.

arch_spin_trylock() can't be used either since in the CONFIG_SMP=n case
no atomic protection is given and we are reentrant here. A mutex didn't
worked either and brings more overhead by turning off interrupts.

So, let's use the fastest path for parisc which is the ldcw instruction.

Counting how often the irq stack was used is pretty useless, so just
drop this piece of code.
Signed-off-by: NHelge Deller <deller@gmx.de>

The get_stack_use_cr30 and get_stack_use_r30 macros allocate a stack
frame for external interrupts and interruptions requiring a stack frame.
They are currently not reentrant in that they save register context
before the stack is set or adjusted.

I have observed a number of system crashes where there was clear
evidence of stack corruption during interrupt processing, and as a
result register corruption. Some interruptions can still occur during
interruption processing, however external interrupts are disabled and
data TLB misses don't occur for absolute accesses. So, it's not entirely
clear what triggers this issue. Also, if an interruption occurs when
Q=0, it is generally not possible to recover as the shadowed registers
are not copied.

The attached patch reworks the get_stack_use_cr30 and get_stack_use_r30
macros to allocate stack before doing register saves. The new code is a
couple of instructions shorter than the old implementation. Thus, it's
an improvement even if it doesn't fully resolve the stack corruption
issue. Based on limited testing, it improves SMP system stability.
Signed-off-by: NJohn David Anglin <dave.anglin@bell.net>
Signed-off-by: NHelge Deller <deller@gmx.de>

Show number of floating point assistant and unaligned access fixup
handler in /proc/interrupts file.
Signed-off-by: NHelge Deller <deller@gmx.de>

additionally clean up some whitespaces & tabs.
Signed-off-by: NHelge Deller <deller@gmx.de>

Signed-off-by: NHelge Deller <deller@gmx.de>

Impact:
1:convert all remain take_over_console to do_take_over_console
2:update take_over_console to do_take_over_console in comment

Commit dc964189 ("vt: delete unneeded functions
register_con_driver|take_over_console") delete take_over_console,
but forget to convert remain take_over_console's users to new API
do_take_over_console, this patch fix it.
Reported-by: NStephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: NWang YanQing <udknight@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Currently, race conditions exist in the handling of TLB interruptions in
entry.S.  In particular, dirty bit updates can be lost if an accessed
interruption occurs just after the dirty bit interruption on a different
cpu.  Lost dirty bit updates result in user pages not being flushed and
general system instability.  This change adds lock and unlock macros to
synchronize all PTE and TLB updates done in entry.S.  As a result,
userspace stability is significantly improved.
Signed-off-by: NJohn David Anglin  <dave.anglin@bell.net>
Signed-off-by: NHelge Deller <deller@gmx.de>

This patch fixes few build issues which were introduced with the last
irq stack patch, e.g. the combination of stack overflow check and irq
stack.

Furthermore we now do proper locking and change the irq bh handler
to use the irq stack as well.

In /proc/interrupts one now can monitor how huge the irq stack has grown
and how often it was preferred over the kernel stack.

IRQ stacks are now enabled by default just to make sure that we not
overflow the kernel stack by accident.
Signed-off-by: NHelge Deller <deller@gmx.de>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

kmap_atomic() requires only one argument now.
Signed-off-by: NZhao Hongjiang <zhaohongjiang@huawei.com>
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: Helge Deller <deller@gmx.de>
Cc: Rolf Eike Beer <eike-kernel@sf-tec.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Fix up build error on UP and show correctly number of function call
(ipi) irqs.
Signed-off-by: NHelge Deller <deller@gmx.de>

Add framework and initial values for more fine grained statistics in
/proc/interrupts.
Signed-off-by: NHelge Deller <deller@gmx.de>

Default kernel stack size on parisc is 16k.  During tests we found that the
kernel stack can easily grow beyond 13k, which leaves 3k left for irq
processing.

This patch adds the possibility to activate an additional stack of 16k per CPU
which is being used during irq processing.  This implementation does not yet
uses this irq stack for the irq bh handler.

The assembler code for call_on_stack was heavily cleaned up by John
David Anglin.

CC: John David Anglin <dave.anglin@bell.net>
Signed-off-by: NHelge Deller <deller@gmx.de>

Add the CONFIG_DEBUG_STACKOVERFLOW config option to enable checks to
detect kernel stack overflows.

Stack overflows can not be detected reliable since we do not want to
introduce too much overhead.

Instead, during irq processing in do_cpu_irq_mask() we check kernel
stack usage of the interrupted kernel process. Kernel threads can be
easily detected by checking the value of space register 7 (sr7) which
is zero when running inside the kernel.

Since THREAD_SIZE is 16k and PAGE_SIZE is 4k, reduce the alignment of
the init thread to the lower value (PAGE_SIZE) in the kernel
vmlinux.ld.S linker script.
Signed-off-by: NHelge Deller <deller@gmx.de>