linux-toradex.git/arch/s390/kernel, branch v3.12.12

s390/vtime: correct idle time calculation

2013-11-29T19:28:12+00:00

commit 4560e7c3317c7a2b370e36dadd3a3bac2ed70818 upstream.

Use the ACCESS_ONCE macro for both accesses to idle->sequence in the
loops to calculate the idle time. If only one access uses the macro,
the compiler is free to cache the value for the second access which
can cause endless loops.

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

s390/time: correct use of store clock fast

2013-10-22T07:16:40+00:00

The result of the store-clock-fast (STCKF) instruction is a bit fuzzy.
It can happen that the value stored on one CPU is smaller than the value
stored on another CPU, although the order of the stores is the other
way around. This can cause deltas of get_tod_clock() values to become
negative when they should not be.

We need to be more careful with store-clock-fast, this patch partially
reverts git commit e4b7b4238e666682555461fa52eecd74652f36bb "time:
always use stckf instead of stck if available". The get_tod_clock()
function now uses the store-clock-extended (STCKE) instruction.
get_tod_clock_fast() can be used if the fuzziness of store-clock-fast
is acceptable e.g. for wait loops local to a CPU.

Signed-off-by: Martin Schwidefsky

s390/compat,signal: fix return value of copy_siginfo_(to|from)_user32()

2013-10-15T11:47:59+00:00

The return value of copy_siginfo_(to|from)_user32() gets passed to
user space, however we do not convert a positive return value from
copy_(to|from)_user to -EFAULT.
Therefore these functions (and the calling system calls) my incorrectly
return a positive number (bytes not copied) instead of -EFAULT.

Signed-off-by: Heiko Carstens 
Signed-off-by: Martin Schwidefsky

s390: fix system call restart after inferior call

2013-09-30T11:04:40+00:00

Git commit 616498813b11ffef "s390: system call path micro optimization"
introduced a regression in regard to system call restarting and inferior
function calls via the ptrace interface. The pointer to the system call
table needs to be loaded in sysc_sigpending if do_signal returns with
TIF_SYSCALl set after it restored a system call context.

Cc: stable@vger.kernel.org # 3.10+
Signed-off-by: Martin Schwidefsky

s390: Allow vmalloc target buffers for copy_from_oldmem()

2013-09-30T11:04:40+00:00

Currently copy_from_oldmem() is not able to copy to virtual memory.
When using kexec pre-allocated ELF header, copy_from_oldmem()
is used to copy the ELF notes information to vmalloc buffers.

So fix this and use the new function copy_from_realmem() that allows
copying also to vmalloc memory.

Signed-off-by: Michael Holzheu 
Signed-off-by: Martin Schwidefsky

s390/kprobes: add exrl to list of prohibited opcodes

2013-09-30T11:04:38+00:00

"execute relative long" may have all sorts of side effects dependend on
the instructions it executes.
Therefore prohibit setting a kprobe on exrl just like we do for the
regular execute instruction.

Signed-off-by: Heiko Carstens 
Signed-off-by: Martin Schwidefsky

s390/vmcore: use vmcore for zfcpdump

2013-09-11T22:59:15+00:00

Modify the s390 copy_oldmem_page() and remap_oldmem_pfn_range() function
for zfcpdump to read from the HSA memory if memory below HSA_SIZE bytes is
requested.  Otherwise real memory is used.

Signed-off-by: Michael Holzheu 
Cc: HATAYAMA Daisuke 
Cc: Jan Willeke 
Cc: Vivek Goyal 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

s390/vmcore: implement remap_oldmem_pfn_range for s390

2013-09-11T22:59:12+00:00

Introduce the s390 specific way to map pages from oldmem.  The memory area
below OLDMEM_SIZE is mapped with offset OLDMEM_BASE.  The other old memory
is mapped directly.

Signed-off-by: Jan Willeke 
Signed-off-by: Michael Holzheu 
Cc: HATAYAMA Daisuke 
Cc: Vivek Goyal 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

s390/vmcore: use ELF header in new memory feature

2013-09-11T22:59:10+00:00

Exchange the old relocate mechanism with the new arch function call
override mechanism that allows to create the ELF core header in the 2nd
kernel.

Signed-off-by: Michael Holzheu 
Cc: HATAYAMA Daisuke 
Cc: Jan Willeke 
Cc: Vivek Goyal 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

s390/kprobes: add support for pc-relative long displacement instructions

2013-09-11T22:58:52+00:00

With the general-instruction extension facility (z10) a couple of
instructions with a pc-relative long displacement were introduced.  The
kprobes support for these instructions however was never implemented.

In result, if anybody ever put a probe on any of these instructions the
result would have been random behaviour after the instruction got executed
within the insn slot.

So lets add the missing handling for these instructions.  Since all of the
new instructions have 32 bit signed displacement the easiest solution is
to allocate an insn slot that is within the same 2GB area like the
original instruction and patch the displacement field.

Signed-off-by: Heiko Carstens 
Reviewed-by: Masami Hiramatsu 
Cc: Ananth N Mavinakayanahalli 
Cc: Ingo Molnar 
Cc: Martin Schwidefsky 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds