linux-toradex.git/arch/powerpc, branch v2.6.35.8

powerpc: Don't use kernel stack with translation off

2010-10-29T04:51:40+00:00

commit 54a834043314c257210db2a9d59f8cc605571639 upstream.

In f761622e59433130bc33ad086ce219feee9eb961 we changed
early_setup_secondary so it's called using the proper kernel stack
rather than the emergency one.

Unfortunately, this stack pointer can't be used when translation is off
on PHYP as this stack pointer might be outside the RMO.  This results in
the following on all non zero cpus:
  cpu 0x1: Vector: 300 (Data Access) at [c00000001639fd10]
      pc: 000000000001c50c
      lr: 000000000000821c
      sp: c00000001639ff90
     msr: 8000000000001000
     dar: c00000001639ffa0
   dsisr: 42000000
    current = 0xc000000016393540
    paca    = 0xc000000006e00200
      pid   = 0, comm = swapper

The original patch was only tested on bare metal system, so it never
caught this problem.

This changes __secondary_start so that we calculate the new stack
pointer but only start using it after we've called early_setup_secondary.

With this patch, the above problem goes away.

Signed-off-by: Michael Neuling 
Signed-off-by: Benjamin Herrenschmidt 
Signed-off-by: Greg Kroah-Hartman

powerpc: Initialise paca->kstack before early_setup_secondary

2010-10-29T04:51:40+00:00

commit f761622e59433130bc33ad086ce219feee9eb961 upstream.

As early setup calls down to slb_initialize(), we must have kstack
initialised before checking "should we add a bolted SLB entry for our kstack?"

Failing to do so means stack access requires an SLB miss exception to refill
an entry dynamically, if the stack isn't accessible via SLB(0) (kernel text
& static data).  It's not always allowable to take such a miss, and
intermittent crashes will result.

Primary CPUs don't have this issue; an SLB entry is not bolted for their
stack anyway (as that lives within SLB(0)).  This patch therefore only
affects the init of secondaries.

Signed-off-by: Matt Evans 
Signed-off-by: Benjamin Herrenschmidt 
Signed-off-by: Greg Kroah-Hartman

compat: Make compat_alloc_user_space() incorporate the access_ok()

2010-09-20T20:36:44+00:00

commit c41d68a513c71e35a14f66d71782d27a79a81ea6 upstream.

compat_alloc_user_space() expects the caller to independently call
access_ok() to verify the returned area.  A missing call could
introduce problems on some architectures.

This patch incorporates the access_ok() check into
compat_alloc_user_space() and also adds a sanity check on the length.
The existing compat_alloc_user_space() implementations are renamed
arch_compat_alloc_user_space() and are used as part of the
implementation of the new global function.

This patch assumes NULL will cause __get_user()/__put_user() to either
fail or access userspace on all architectures.  This should be
followed by checking the return value of compat_access_user_space()
for NULL in the callers, at which time the access_ok() in the callers
can also be removed.

Reported-by: Ben Hawkes 
Signed-off-by: H. Peter Anvin 
Acked-by: Benjamin Herrenschmidt 
Acked-by: Chris Metcalf 
Acked-by: David S. Miller 
Acked-by: Ingo Molnar 
Acked-by: Thomas Gleixner 
Acked-by: Tony Luck 
Cc: Andrew Morton 
Cc: Arnd Bergmann 
Cc: Fenghua Yu 
Cc: H. Peter Anvin 
Cc: Heiko Carstens 
Cc: Helge Deller 
Cc: James Bottomley 
Cc: Kyle McMartin 
Cc: Martin Schwidefsky 
Cc: Paul Mackerras 
Cc: Ralf Baechle 
Signed-off-by: Greg Kroah-Hartman

powerpc/perf_event: Reduce latency of calling perf_event_do_pending

2010-09-20T20:36:41+00:00

commit b0d278b7d3ae9115939ddcea93f516308cc367e2 upstream.

Commit 0fe1ac48 ("powerpc/perf_event: Fix oops due to
perf_event_do_pending call") moved the call to perf_event_do_pending
in timer_interrupt() down so that it was after the irq_enter() call.
Unfortunately this moved it after the code that checks whether it
is time for the next decrementer clock event.  The result is that
the call to perf_event_do_pending() won't happen until the next
decrementer clock event is due.  This was pointed out by Milton
Miller.

This fixes it by moving the check for whether it's time for the
next decrementer clock event down to the point where we're about
to call the event handler, after we've called perf_event_do_pending.

This has the side effect that on old pre-Core99 Powermacs where we
use the ppc_n_lost_interrupts mechanism to replay interrupts, a
replayed interrupt will incur a little more latency since it will
now do the code from the irq_enter down to the irq_exit, that it
used to skip.  However, these machines are now old and rare enough
that this doesn't matter.  To make it clear that ppc_n_lost_interrupts
is only used on Powermacs, and to speed up the code slightly on
non-Powermac ppc32 machines, the code that tests ppc_n_lost_interrupts
is now conditional on CONFIG_PMAC as well as CONFIG_PPC32.

Signed-off-by: Paul Mackerras 
Signed-off-by: Benjamin Herrenschmidt 
Signed-off-by: Greg Kroah-Hartman

powerpc: Fix typo in uImage target

2010-08-26T23:46:23+00:00

commit c686ecf5040d287a68d4fca7f1948472f556a6d3 upstream.

Commit e32e78c5ee8aadef020fbaecbe6fb741ed9029fd
(powerpc: fix build with make 3.82) introduced a
typo in uImage target and broke building uImage:

make: *** No rule to make target `uImage'.  Stop.

Signed-off-by: Anatolij Gustschin 
Signed-off-by: Benjamin Herrenschmidt 
Signed-off-by: Greg Kroah-Hartman

powerpc: fix build with make 3.82

2010-08-13T20:30:37+00:00

commit e32e78c5ee8aadef020fbaecbe6fb741ed9029fd upstream.

Thomas Backlund reported that the powerpc build broke with make 3.82.
It failed with the following message:

    arch/powerpc/Makefile:183: *** mixed implicit and normal rules.  Stop.

The fix is to avoid mixing non-wildcard and wildcard targets.

Reported-by: Thomas Backlund 
Tested-by: Thomas Backlund 
Cc: Michal Marek 
Signed-off-by: Sam Ravnborg 
Signed-off-by: Benjamin Herrenschmidt 
Signed-off-by: Greg Kroah-Hartman

perf, powerpc: fsl_emb: Restore setting perf_sample_data.period

2010-08-13T20:30:37+00:00

commit 69e77a8b0426ded5d924eea7dbe4eca51e09f530 upstream.

Commit 6b95ed345b9faa4ab3598a82991968f2e9f851bb changed from
a struct initializer to perf_sample_data_init(), but the setting
of the .period member was left out.

Signed-off-by: Scott Wood 
Signed-off-by: Paul Mackerras 
Signed-off-by: Greg Kroah-Hartman

perf, powerpc: Use perf_sample_data_init() for the FSL code

2010-07-27T12:20:09+00:00

We should use perf_sample_data_init() to initialize struct
perf_sample_data.  As explained in the description of commit dc1d628a
("perf: Provide generic perf_sample_data initialization"), it is
possible for userspace to get the kernel to dereference data.raw,
so if it is not initialized, that means that unprivileged userspace
can possibly oops the kernel.  Using perf_sample_data_init makes sure
it gets initialized to NULL.

This conversion should have been included in commit dc1d628a, but it
got missed.

Signed-off-by: Peter Zijlstra 
Acked-by: Kumar Gala 
Signed-off-by: Paul Mackerras

Merge commit 'kumar/merge' into merge

2010-07-23T03:46:21+00:00

powerpc: Fix erroneous lmb->memblock conversions

2010-07-23T02:56:57+00:00

Oooops... we missed these. We incorrectly converted strings
used when parsing the device-tree on pseries, thus breaking
access to drconf memory and hotplug memory.

While at it, also revert some variable names that represent
something the FW calls "lmb" and thus don't need to be converted
to "memblock".

Signed-off-by: Benjamin Herrenschmidt 
---