linux-stable.git/arch/powerpc/include, branch v4.16.7

powerpc/powernv: define a standard delay for OPAL_BUSY type retry loops

2018-04-24T07:42:56+00:00

commit 34dd25de9fe3f60bfdb31b473bf04b28262d0896 upstream.

This is the start of an effort to tidy up and standardise all the
delays. Existing loops have a range of delay/sleep periods from 1ms
to 20ms, and some have no delay. They all loop forever except rtc,
which times out after 10 retries, and that uses 10ms delays. So use
10ms as our standard delay. The OPAL maintainer agrees 10ms is a
reasonable starting point.

The idea is to use the same recipe everywhere, once this is proven to
work then it will be documented as an OPAL API standard. Then both
firmware and OS can agree, and if a particular call needs something
else, then that can be documented with reasoning.

This is not the end-all of this effort, it's just a relatively easy
change that fixes some existing high latency delays. There should be
provision for standardising timeouts and/or interruptible loops where
possible, so non-fatal firmware errors don't cause hangs.

Signed-off-by: Nicholas Piggin 
Signed-off-by: Michael Ellerman 
Cc: Nathan Chancellor 
Cc: Guenter Roeck 
Signed-off-by: Greg Kroah-Hartman

powerpc/64: Fix smp_wmb barrier definition use use lwsync consistently

2018-04-24T07:42:55+00:00

commit 0bfdf598900fd62869659f360d3387ed80eb71cf upstream.

asm/barrier.h is not always included after asm/synch.h, which meant
it was missing __SUBARCH_HAS_LWSYNC, so in some files smp_wmb() would
be eieio when it should be lwsync. kernel/time/hrtimer.c is one case.

__SUBARCH_HAS_LWSYNC is only used in one place, so just fold it in
to where it's used. Previously with my small simulator config, 377
instances of eieio in the tree. After this patch there are 55.

Fixes: 46d075be585e ("powerpc: Optimise smp_wmb")
Cc: stable@vger.kernel.org # v2.6.29+
Signed-off-by: Nicholas Piggin 
Signed-off-by: Michael Ellerman 
Signed-off-by: Greg Kroah-Hartman

powerpc/mm: Fixup tlbie vs store ordering issue on POWER9

2018-03-23T09:48:03+00:00

On POWER9, under some circumstances, a broadcast TLB invalidation
might complete before all previous stores have drained, potentially
allowing stale stores from becoming visible after the invalidation.
This works around it by doubling up those TLB invalidations which was
verified by HW to be sufficient to close the risk window.

This will be documented in a yet-to-be-published errata.

Fixes: 1a472c9dba6b ("powerpc/mm/radix: Add tlbflush routines")
Signed-off-by: Aneesh Kumar K.V 
[mpe: Enable the feature in the DT CPU features code for all Power9,
      rename the feature to CPU_FTR_P9_TLBIE_BUG per benh.]
Signed-off-by: Michael Ellerman

powerpc/mm/radix: Remove unused code

2018-03-23T05:17:39+00:00

These function are not used in the code. Remove them.

Signed-off-by: Aneesh Kumar K.V 
Signed-off-by: Michael Ellerman

powerpc/mm: Add tracking of the number of coprocessors using a context

2018-03-23T03:14:31+00:00

Currently, when using coprocessors (which use the Nest MMU), we
simply increment the active_cpu count to force all TLB invalidations
to be come broadcast.

Unfortunately, due to an errata in POWER9, we will need to know
more specifically that coprocessors are in use.

This maintains a separate copros counter in the MMU context for
that purpose.

NB. The commit mentioned in the fixes tag below is not at fault for
the bug we're fixing in this commit and the next, but this fix applies
on top the infrastructure it introduced.

Fixes: 03b8abedf4f4 ("cxl: Enable global TLBIs for cxl contexts")
Cc: stable@vger.kernel.org # v4.15+
Signed-off-by: Benjamin Herrenschmidt 
Tested-by: Balbir Singh 
Signed-off-by: Michael Ellerman

powerpc/pseries: Fix duplicate firmware feature for DRC_INFO

2018-02-22T03:32:32+00:00

We had a mid-air collision between two new firmware features, DRMEM_V2
and DRC_INFO, and they ended up with the same value.

No one's actually reported any problems, presumably because the new
firmware that supports both properties is not widely available, and
the two properties tend to be enabled together.

Still if we ever had one enabled but not the other, the bugs that
could result are many and varied. So fix it.

Fixes: 3f38000eda48 ("powerpc/firmware: Add definitions for new drc-info firmware feature")
Signed-off-by: Michael Ellerman 
Reviewed-by: Tyrel Datwyler

powerpc/pseries: Add empty update_numa_cpu_lookup_table() for NUMA=n

2018-02-14T23:10:02+00:00

When CONFIG_NUMA is not set, the build fails with:

  arch/powerpc/platforms/pseries/hotplug-cpu.c:335:4:
  error: déclaration implicite de la fonction « update_numa_cpu_lookup_table »

So we have to add update_numa_cpu_lookup_table() as an empty function
when CONFIG_NUMA is not set.

Fixes: 1d9a090783be ("powerpc/numa: Invalidate numa_cpu_lookup_table on cpu remove")
Signed-off-by: Corentin Labbe 
Signed-off-by: Michael Ellerman

Merge tag 'powerpc-4.16-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

2018-02-14T18:06:41+00:00

Pull powerpc fixes from Michael Ellerman:
 "A larger batch of fixes than we'd like. Roughly 1/3 fixes for new
  code, 1/3 fixes for stable and 1/3 minor things.

  There's four commits fixing bugs when using 16GB huge pages on hash,
  caused by some of the preparatory changes for pkeys.

  Two fixes for bugs in the enhanced IRQ soft masking for local_t, one
  of which broke KVM in some circumstances.

  Four fixes for Power9. The most bizarre being a bug where futexes
  stopped working because a NULL pointer dereference didn't trap during
  early boot (it aliased the kernel mapping). A fix for memory hotplug
  when using the Radix MMU, and a fix for live migration of guests using
  the Radix MMU.

  Two fixes for hotplug on pseries machines. One where we weren't
  correctly updating NUMA info when CPUs are added and removed. And the
  other fixes crashes/hangs seen when doing memory hot remove during
  boot, which is apparently a thing people do.

  Finally a handful of build fixes for obscure configs and other minor
  fixes.

  Thanks to: Alexey Kardashevskiy, Aneesh Kumar K.V, Balbir Singh, Colin
  Ian King, Daniel Henrique Barboza, Florian Weimer, Guenter Roeck,
  Harish, Laurent Vivier, Madhavan Srinivasan, Mauricio Faria de
  Oliveira, Nathan Fontenot, Nicholas Piggin, Sam Bobroff"

* tag 'powerpc-4.16-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  selftests/powerpc: Fix to use ucontext_t instead of struct ucontext
  powerpc/kdump: Fix powernv build break when KEXEC_CORE=n
  powerpc/pseries: Fix build break for SPLPAR=n and CPU hotplug
  powerpc/mm/hash64: Zero PGD pages on allocation
  powerpc/mm/hash64: Store the slot information at the right offset for hugetlb
  powerpc/mm/hash64: Allocate larger PMD table if hugetlb config is enabled
  powerpc/mm: Fix crashes with 16G huge pages
  powerpc/mm: Flush radix process translations when setting MMU type
  powerpc/vas: Don't set uses_vas for kernel windows
  powerpc/pseries: Enable RAS hotplug events later
  powerpc/mm/radix: Split linear mapping on hot-unplug
  powerpc/64s/radix: Boot-time NULL pointer protection using a guard-PID
  ocxl: fix signed comparison with less than zero
  powerpc/64s: Fix may_hard_irq_enable() for PMI soft masking
  powerpc/64s: Fix MASKABLE_RELON_EXCEPTION_HV_OOL macro
  powerpc/numa: Invalidate numa_cpu_lookup_table on cpu remove

powerpc/kdump: Fix powernv build break when KEXEC_CORE=n

2018-02-13T11:39:37+00:00

If KEXEC_CORE is not enabled, powernv builds fail as follows.

  arch/powerpc/platforms/powernv/smp.c: In function 'pnv_smp_cpu_kill_self':
  arch/powerpc/platforms/powernv/smp.c:236:4: error:
  	implicit declaration of function 'crash_ipi_callback'

Add dummy function calls, similar to kdump_in_progress(), to solve the
problem.

Fixes: 4145f358644b ("powernv/kdump: Fix cases where the kdump kernel can get HMI's")
Signed-off-by: Guenter Roeck 
Acked-by: Balbir Singh 
Signed-off-by: Michael Ellerman

powerpc/pseries: Fix build break for SPLPAR=n and CPU hotplug

2018-02-13T11:38:39+00:00

Commit e67e02a544e9 ("powerpc/pseries: Fix cpu hotplug crash with
memoryless nodes") adds an unconditional call to
find_and_online_cpu_nid(), which is only declared if CONFIG_PPC_SPLPAR
is enabled. This results in the following build error if this is not
the case.

  arch/powerpc/platforms/pseries/hotplug-cpu.o: In function `dlpar_online_cpu':
  arch/powerpc/platforms/pseries/hotplug-cpu.c:369:
  			undefined reference to `.find_and_online_cpu_nid'

Follow the guideline provided by similar functions and provide a dummy
function if CONFIG_PPC_SPLPAR is not enabled. This also moves the
external function declaration into an include file where it should be.

Fixes: e67e02a544e9 ("powerpc/pseries: Fix cpu hotplug crash with memoryless nodes")
Signed-off-by: Guenter Roeck 
[mpe: Change subject to emphasise the build fix]
Signed-off-by: Michael Ellerman