litmus-rt.git/arch/s390, branch linux-tip

[S390] nmi: fix clock comparator revalidation

2010-11-25T08:52:59+00:00

On each machine check all registers are revalidated. The save area for
the clock comparator however only contains the upper most seven bytes
of the former contents, if valid.
Therefore the machine check handler uses a store clock instruction to
get the current time and writes that to the clock comparator register
which in turn will generate an immediate timer interrupt.
However within the lowcore the expected time of the next timer
interrupt is stored. If the interrupt happens before that time the
handler won't be called. In turn the clock comparator won't be
reprogrammed and therefore the interrupt condition stays pending which
causes an interrupt loop until the expected time is reached.

On NOHZ machines this can result in unresponsive machines since the
time of the next expected interrupted can be a couple of days in the
future.

To fix this just revalidate the clock comparator register with the
expected value.
In addition the special handling for udelay must be changed as well.

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

BKL: remove extraneous #include

2010-11-17T16:59:32+00:00

The big kernel lock has been removed from all these files at some point,
leaving only the #include.

Remove this too as a cleanup.

Signed-off-by: Arnd Bergmann 
Signed-off-by: Linus Torvalds

[S390] kprobes: Fix the return address of multiple kretprobes

2010-11-10T09:05:54+00:00

Analog to git commit 737480a0d525dae13306296da08029dff545bc72
fix the return address of subsequent kretprobes when multiple
kretprobes are set on the same function.

Signed-off-by: Martin Schwidefsky

[S390] kprobes: disable interrupts throughout

2010-11-10T09:05:54+00:00

Execute the kprobe exception and fault handler with interrupts disabled.
To disable the interrupts only while a single step is in progress is not
good enough, a kprobe from interrupt context while another kprobe is
handled can confuse the internal house keeping.

Signed-off-by: Martin Schwidefsky

[S390] mm: add devmem_is_allowed() for STRICT_DEVMEM checking

2010-11-10T09:05:54+00:00

Provide the devmem_is_allowed() routine to restrict access to
kernel memory from userspace.
Set the CONFIG_STRICT_DEVMEM config option to switch on checking.

Signed-off-by: Hendrik Brueckner 
Signed-off-by: Martin Schwidefsky

[S390] fix get_user_pages_fast

2010-11-10T09:05:53+00:00

The check for the _PAGE_RO bit in get_user_pages_fast for write==1 is
the wrong way around. It must not be set for the fast path.

Signed-off-by: Martin Schwidefsky

Merge branch 'for-linus' of git://git390.marist.edu/pub/scm/linux-2.6

2010-10-29T15:49:18+00:00

* 'for-linus' of git://git390.marist.edu/pub/scm/linux-2.6:
  [S390] fix kprobes single stepping
  [S390] tape: fix dbf usage
  [S390] dasd: provide a Sense Path Group ID ioctl
  [S390] ftrace: select HAVE_C_RECORDMCOUNT
  [S390] vdso: get rid of redefinition warnings
  [S390] facility detection: remove unused variable
  [S390] hypfs: Fix error handling in hypfs_diag initialization
  [S390] topology: fix cpu masks for topology=off case
  [S390] topology: add SCHED_MC config option
  [S390] Kconfig: add machine type number to code generation options
  [S390] Add z196 machine type to setup_hwcaps

[S390] fix kprobes single stepping

2010-10-29T14:50:50+00:00

Fix kprobes after git commit 1e54622e0403891b10f2105663e0f9dd595a1f17
broke it. The kprobe_handler is now called with interrupts in the state
at the time of the breakpoint. The single step of the replaced instruction
is done with interrupts off which makes it necessary to enable and disable
the interupts in the kprobes code.

Signed-off-by: Martin Schwidefsky

[S390] dasd: provide a Sense Path Group ID ioctl

2010-10-29T14:50:50+00:00

The BIODASDSNID ioctl executes a 'Sense Path Group ID'
command on a DASD ECKD device. The returned path group data
allows user space programs to determine path state and
path group ID of the channel paths to the device.

Signed-off-by: Stefan Weinhuber 
Signed-off-by: Martin Schwidefsky

[S390] ftrace: select HAVE_C_RECORDMCOUNT

2010-10-29T14:50:50+00:00

Select HAVE_C_RECORDMCOUNT for the fast C version of recordmcount.

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