linux.git/arch/powerpc/kernel, branch v2.6.39

hw_breakpoints, powerpc: Fix CONFIG_HAVE_HW_BREAKPOINT off-case in ptrace_set_debugreg()

2011-05-06T09:24:46+00:00

We make use of ptrace_get_breakpoints() / ptrace_put_breakpoints() to
protect ptrace_set_debugreg() even if CONFIG_HAVE_HW_BREAKPOINT if off.
However in this case, these APIs are not implemented.

To fix this, push the protection down inside the relevant ifdef.
Best would be to export the code inside
CONFIG_HAVE_HW_BREAKPOINT into a standalone function to cleanup
the ifdefury there and call the breakpoint ref API inside. But
as it is more invasive, this should be rather made in an -rc1.

Fixes this build error:

  arch/powerpc/kernel/ptrace.c:1594: error: implicit declaration of function 'ptrace_get_breakpoints' make[2]: ***

Reported-by: Ingo Molnar 
Signed-off-by: Frederic Weisbecker 
Cc: LPPC 
Cc: Prasad 
Cc: v2.6.33.. 
Link: http://lkml.kernel.org/r/1304639598-4707-1-git-send-email-fweisbec@gmail.com
Signed-off-by: Ingo Molnar

powerpc, hw_breakpoints: Fix racy access to ptrace breakpoints

2011-04-25T15:33:54+00:00

While the tracer accesses ptrace breakpoints, the child task may
concurrently exit due to a SIGKILL and thus release its breakpoints
at the same time. We can then dereference some freed pointers.

To fix this, hold a reference on the child breakpoints before
manipulating them.

Reported-by: Oleg Nesterov 
Signed-off-by: Frederic Weisbecker 
Acked-by: Prasad 
Cc: Ingo Molnar 
Cc: Peter Zijlstra 
Cc: Will Deacon 
Cc: Paul Mundt 
Cc: v2.6.33.. 
Link: http://lkml.kernel.org/r/1302284067-7860-4-git-send-email-fweisbec@gmail.com

powerpc/perf_event: Skip updating kernel counters if register value shrinks

2011-04-18T03:08:23+00:00

Because of speculative event roll back, it is possible for some event coutners
to decrease between reads on POWER7.  This causes a problem with the way that
counters are updated.  Delta calues are calculated in a 64 bit value and the
top 32 bits are masked.  If the register value has decreased, this leaves us
with a very large positive value added to the kernel counters.  This patch
protects against this by skipping the update if the delta would be negative.
This can lead to a lack of precision in the coutner values, but from my testing
the value is typcially fewer than 10 samples at a time.

Signed-off-by: Eric B Munson 
Cc: stable@kernel.org
Signed-off-by: Benjamin Herrenschmidt

powerpc: Fix oops if scan_dispatch_log is called too early

2011-04-18T03:08:19+00:00

We currently enable interrupts before the dispatch log for the boot
cpu is setup. If a timer interrupt comes in early enough we oops in
scan_dispatch_log:

Unable to handle kernel paging request for data at address 0x00000010

...

.scan_dispatch_log+0xb0/0x170
.account_system_vtime+0xa0/0x220
.irq_enter+0x88/0xc0
.do_IRQ+0x48/0x230

The patch below adds a check to scan_dispatch_log to ensure the
dispatch log has been allocated.

Signed-off-by: Anton Blanchard 
Cc: 
Signed-off-by: Benjamin Herrenschmidt

powerpc/kexec: Fix regression causing compile failure on UP

2011-04-18T03:06:45+00:00

Recent commit b987812b3fcaf70fdf0037589e5d2f5f2453e6ce caused
a compile failure on UP because a considerably large block
of the file was included within CONFIG_SMP, hence making a stub
function not exposed on UP builds when it needed to be.

Relocate the stub to the #else /* ! CONFIG_SMP */ section
and also annotate the relevant else/endif so that nobody
else falls into the same trap I did.

Reported-by: Michael Guntsche 
Signed-off-by: Paul Gortmaker 
Signed-off-by: Benjamin Herrenschmidt

Merge remote branch 'kumar/merge' into merge

2011-04-18T02:09:37+00:00

powerpc/book3e: Fix CPU feature handling on 64-bit e5500

2011-04-12T11:29:21+00:00

The CPU_FTRS_POSSIBLE and CPU_FTRS_ALWAYS defines did not encompass
e5500 CPU features when built for 64-bit.  This causes issues with
cpu_has_feature() as it utilizes the POSSIBLE & ALWAYS defines as part
of its check.

Create a unique CPU_FTRS_E5500 (as its different from CPU_FTRS_E500MC),
created a new group for 64-bit Book3e based CPUs and add CPU_FTRS_E5500
to that group.

Signed-off-by: Kumar Gala

powerpc: Check device status before adding serial device

2011-04-12T11:29:21+00:00

serial port nodes with the property status="disabled" are not usable and so
avoid adding "disabled" port with the system.

Signed-off-by: Prabhakar Kushwaha 
Signed-off-by: Kumar Gala

PM / Hibernate: Introduce CONFIG_HIBERNATE_CALLBACKS

2011-04-11T20:54:42+00:00

Xen save/restore is going to use hibernate device callbacks for
quiescing devices and putting them back to normal operations and it
would need to select CONFIG_HIBERNATION for this purpose.  However,
that also would cause the hibernate interfaces for user space to be
enabled, which might confuse user space, because the Xen kernels
don't support hibernation.  Moreover, it would be wasteful, as it
would make the Xen kernels include a substantial amount of code that
they would never use.

To address this issue introduce new power management Kconfig option
CONFIG_HIBERNATE_CALLBACKS, such that it will only select the code
that is necessary for the hibernate device callbacks to work and make
CONFIG_HIBERNATION select it.  Then, Xen save/restore will be able to
select CONFIG_HIBERNATE_CALLBACKS without dragging the entire
hibernate code along with it.

Signed-off-by: Rafael J. Wysocki 
Tested-by: Shriram Rajagopalan

Merge branch 'for-linus2' of git://git.profusion.mobi/users/lucas/linux-2.6

2011-04-07T18:14:49+00:00

* 'for-linus2' of git://git.profusion.mobi/users/lucas/linux-2.6:
  Fix common misspellings