linux-toradex.git/arch/parisc/kernel, branch v3.12.6

parisc: fix mmap(MAP_FIXED|MAP_SHARED) to already mmapped address

2013-12-12T06:37:54+00:00

commit 0576da2c08e3d332f1b0653030d28ab804585ab6 upstream.

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: Helge Deller 
Signed-off-by: Greg Kroah-Hartman

parisc: Do not crash 64bit SMP kernels on machines with >= 4GB RAM

2013-10-27T14:58:44+00:00

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: Helge Deller 
Signed-off-by: John David Anglin 
Cc:  # 2.6.12+
Signed-off-by: Helge Deller

Revert "parisc: Export flush_cache_page() (needed by lustre)"

2013-10-19T19:37:40+00:00

This reverts commit 320c90be7ba1c371e882edff57272a89b213d136.

Christoph Hellwig  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: Helge Deller

parisc: fix interruption handler to respect pagefault_disable()

2013-10-13T15:45:20+00:00

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: Helge Deller 
Cc:  # v3.0+
Signed-off-by: John David Anglin  
Signed-off-by: Helge Deller

parisc: remove unused syscall_ipi() function.

2013-10-13T15:44:39+00:00

Signed-off-by: Helge Deller

parisc: kill SMP single function call interrupt

2013-10-13T15:44:29+00:00

Commit 9a46ad6d6df3b54 "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: Jiang Liu 
Cc: Jiang Liu 
Signed-off-by: Helge Deller

parisc: Export flush_cache_page() (needed by lustre)

2013-10-13T15:44:17+00:00

ERROR: "flush_cache_page" [drivers/staging/lustre/lustre/libcfs/libcfs.ko] undefined!

Signed-off-by: Geert Uytterhoeven 
Signed-off-by: Helge Deller

Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial

2013-09-06T16:36:28+00:00

Pull trivial tree from Jiri Kosina:
 "The usual trivial updates all over the tree -- mostly typo fixes and
  documentation updates"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (52 commits)
  doc: Documentation/cputopology.txt fix typo
  treewide: Convert retrun typos to return
  Fix comment typo for init_cma_reserved_pageblock
  Documentation/trace: Correcting and extending tracepoint documentation
  mm/hotplug: fix a typo in Documentation/memory-hotplug.txt
  power: Documentation: Update s2ram link
  doc: fix a typo in Documentation/00-INDEX
  Documentation/printk-formats.txt: No casts needed for u64/s64
  doc: Fix typo "is is" in Documentations
  treewide: Fix printks with 0x%#
  zram: doc fixes
  Documentation/kmemcheck: update kmemcheck documentation
  doc: documentation/hwspinlock.txt fix typo
  PM / Hibernate: add section for resume options
  doc: filesystems : Fix typo in Documentations/filesystems
  scsi/megaraid fixed several typos in comments
  ppc: init_32: Fix error typo "CONFIG_START_KERNEL"
  treewide: Add __GFP_NOWARN to k.alloc calls with v.alloc fallbacks
  page_isolation: Fix a comment typo in test_pages_isolated()
  doc: fix a typo about irq affinity
  ...

treewide: Fix printks with 0x%#

2013-08-27T08:49:38+00:00

Using 0x%# emits 0x0x.  Only one is necessary.

Signed-off-by: Joe Perches 
Acked-by: Takashi Iwai 
Signed-off-by: Jiri Kosina

parisc: Fix interrupt routing for C8000 serial ports

2013-07-31T21:42:32+00:00

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: Thomas Bogendoerfer 
Cc:  # 3.10
Signed-off-by: Helge Deller