linux-stable.git/arch/s390, branch linux-3.6.y

s390/signal: set correct address space control

2012-11-26T20:14:21+00:00

commit fa968ee215c0ca91e4a9c3a69ac2405aae6e5d2f upstream.

If user space is running in primary mode it can switch to secondary
or access register mode, this is used e.g. in the clock_gettime code
of the vdso. If a signal is delivered to the user space process while
it has been running in access register mode the signal handler is
executed in access register mode as well which will result in a crash
most of the time.

Set the address space control bits in the PSW to the default for the
execution of the signal handler and make sure that the previous
address space control is restored on signal return. Take care
that user space can not switch to the kernel address space by
modifying the registers in the signal frame.

Signed-off-by: Martin Schwidefsky 
Signed-off-by: Greg Kroah-Hartman

s390/gup: add missing TASK_SIZE check to get_user_pages_fast()

2012-11-26T20:14:11+00:00

commit d55c4c613fc4d4ad2ba0fc6fa2b57176d420f7e4 upstream.

When walking page tables we need to make sure that everything
is within bounds of the ASCE limit of the task's address space.
Otherwise we might calculate e.g. a pud pointer which is not
within a pud and dereference it.
So check against TASK_SIZE (which is the ASCE limit) before
walking page tables.

Reviewed-by: Gerald Schaefer 
Signed-off-by: Heiko Carstens 
Signed-off-by: Martin Schwidefsky 
Signed-off-by: Greg Kroah-Hartman

s390: fix linker script for 31 bit builds

2012-10-28T17:56:10+00:00

commit c985cb37f1b39c2c8035af741a2a0b79f1fbaca7 upstream.

Because of a change in the s390 arch backend of binutils (commit 23ecd77
"Pick the default arch depending on the target size" in binutils repo)
31 bit builds will fail since the linker would now try to create 64 bit
binary output.
Fix this by setting OUTPUT_ARCH to s390:31-bit instead of s390.
Thanks to Andreas Krebbel for figuring out the issue.

Fixes this build error:

  LD      init/built-in.o
s390x-4.7.2-ld: s390:31-bit architecture of input file
 `arch/s390/kernel/head.o' is incompatible with s390:64-bit output

Cc: Andreas Krebbel 
Signed-off-by: Heiko Carstens 
Signed-off-by: Martin Schwidefsky 
Signed-off-by: Greg Kroah-Hartman

Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux

2012-09-21T19:10:17+00:00

Pull s390 fixes from Martin Schwidefsky:
 "Bug fixes for 3.6-rc7, including some important patches for large page
  related memory management issues."

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
  s390/dasd: fix read unit address configuration loop
  s390/dasd: fix pathgroup race
  s390/mm: fix user access page-table walk code
  s390/hwcaps: do not report high gprs for 31 bit kernel
  s390/cio: invalidate cdev pointer before deregistration
  s390/cio: fix IO subchannel event race
  s390/dasd: move wake_up call
  s390/hugetlb: use direct TLB flushing for hugetlbfs pages
  s390/mm: fix deadlock in unmap_hugepage_range()

s390/mm: fix user access page-table walk code

2012-09-17T07:44:24+00:00

The s390 page-table walk code, used for user copy and futex, currently
cannot handle huge pages. As far as user copy is concerned, that is
not really a problem because those functions will only be used on old
hardware that has no huge page support. But the futex code will also
use pagetable walk functions on current hardware when user space runs
in primary space mode. So, if a futex sits in a huge page, the futex
operation on it will result in a page fault loop or even data
corruption.

This patch adds the code for resolving huge page mappings in the user
access pagetable walk code on s390.

Signed-off-by: Gerald Schaefer 
Signed-off-by: Martin Schwidefsky

Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2012-09-15T00:43:45+00:00

Pull perf fixes from Ingo Molnar:
 "This tree includes various fixes"

Ingo really needs to improve on the whole "explain git pull" part.
"Various fixes" indeed.

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf/hwpb: Invoke __perf_event_disable() if interrupts are already disabled
  perf/x86: Enable Intel Cedarview Atom suppport
  perf_event: Switch to internal refcount, fix race with close()
  oprofile, s390: Fix uninitialized memory access when writing to oprofilefs
  perf/x86: Fix microcode revision check for SNB-PEBS

s390/hwcaps: do not report high gprs for 31 bit kernel

2012-09-10T07:53:52+00:00

The bit for high gprs in the AT_HWCAP auxiliary vector field and the
highgprs tag in the output of /proc/cpuinfo should not be set for
31 bit kernels.

Signed-off-by: Martin Schwidefsky

s390/hugetlb: use direct TLB flushing for hugetlbfs pages

2012-09-06T08:40:37+00:00

huge_ptep_get_and_clear() is either missing a TLB invalidation or
an mm->context.attach_count check. Since the attach_count logic was
introduced with normal ptes in mind, let's just use direct TLB
flushing for hugetlbfs pages.

Signed-off-by: Gerald Schaefer 
Signed-off-by: Martin Schwidefsky

s390/mm: fix deadlock in unmap_hugepage_range()

2012-09-03T09:14:06+00:00

git commit cd2934a3 moved the flush_tlb_range() within
__unmap_hugepage_range() inside the mm->page_table_lock, which
triggered a deadlock in s390 tlb flushing code. __tlb_flush_mm_cond()
also tries to acquire the mm->page_table_lock, but that is not needed
because all callers already have mm->mmap_sem or mm->page_table_lock,
so it can be safely removed to fix the deadlock.

Signed-off-by: Gerald Schaefer 
Signed-off-by: Martin Schwidefsky

s390/32: Don't clobber personality flags on exec

2012-08-30T14:28:07+00:00

In native 32 bit mode the personality flags were not correctly inherited.
This is the s390 version of 59e4c3a2 "powerpc/32: Don't clobber personality
flags on exec".

Reported-by: Mike Frysinger 
Signed-off-by: Heiko Carstens 
Signed-off-by: Martin Schwidefsky