Commit Graph

4529 Commits

Author SHA1 Message Date
Anton Blanchard
c54b2bf1b5 powerpc: Add ppc64 hard lockup detector support
The hard lockup detector uses a PMU event as a periodic NMI to
detect if we are stuck (where stuck means no timer interrupts have
occurred).

Ben's rework of the ppc64 soft disable code has made ppc64 PMU
exceptions a partial NMI. They can get disabled if an external
interrupt comes in, but otherwise PMU interrupts will fire in
interrupt disabled regions.

We disable the hard lockup detector by default for a few reasons:

- It breaks userspace event based branches on POWER8.
- It is likely to produce false positives on KVM guests.
- Since PMCs can only count to 2^31, counting cycles means we might
  take multiple PMU exceptions per second per hardware thread even
  if our hard lockup timeout is 10 seconds.

It can be enabled via a boot option, or via procfs.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-04-11 20:49:27 +10:00
Sam bobroff
feba40362b powerpc/tm: Abort syscalls in active transactions
This patch changes the syscall handler to doom (tabort) active
transactions when a syscall is made and return immediately without
performing the syscall.

Currently, the system call instruction automatically suspends an
active transaction which causes side effects to persist when an active
transaction fails.

This does change the kernel's behaviour, but in a way that was
documented as unsupported. It doesn't reduce functionality because
syscalls will still be performed after tsuspend. It also provides a
consistent interface and makes the behaviour of user code
substantially the same across powerpc and platforms that do not
support suspended transactions (e.g. x86 and s390).

Performance measurements using
http://ozlabs.org/~anton/junkcode/null_syscall.c
indicate the cost of a system call increases by about 0.5%.

Signed-off-by: Sam Bobroff <sam.bobroff@au1.ibm.com>
Acked-By: Michael Neuling <mikey@neuling.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-04-11 20:49:19 +10:00
Daniel Axtens
467efc2e4f powerpc: Remove shims for pci_controller_ops operations
Remove shims, patch callsites to use pci_controller_ops
versions instead.

Also move back the probe mode defines, as explained in the patch
for pci_probe_mode.

Signed-off-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-04-11 20:49:18 +10:00
Daniel Axtens
97884e00e2 powerpc: fsl_pci, swiotlb: Move controller ops from ppc_md to controller_ops
Move the installation of DMA operations out of swiotlb's subsys
initcall, and into the generic PCI controller operations struct.

These ops are installed conditionally, based on the ppc_swiotlb_enable
global. The global can be set in two places:
 - swiotlb_detect_4g, which is always called at the arch initcall level
 - setup_pci_atmu, which is called as part of the fsl_add_bridge and
fsl_pci_syscore_do_resume.

fsl_pci_syscore_do_resume is called late enough that any changes as a
result of that call will have no effect.

As such, if we test the global and set the operations as part of
fsl_add_bridge, after the call to setup_pci_atmu, we can be confident
that it will cover all the PCI implementations affected by the changes
to dma-swiotlb.c.

Signed-off-by: Daniel Axtens <dja@axtens.net>
Acked-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-04-11 20:49:17 +10:00
Daniel Axtens
cd16c7ba0c powerpc: Create pci_controller_ops.reset_secondary_bus and shim
Add pci_controller_ops.reset_secondary_bus,
shadowing ppc_md.pcibios_reset_secondary_bus.
Add a shim, and changes the callsites to use the shim.

Use pcibios_reset_secondary_bus_shim, as both
pcibios_reset_secondary_bus and pci_reset_secondary_bus
are already taken.

Signed-off-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-04-11 20:49:14 +10:00
Daniel Axtens
542070baf4 powerpc: Create pci_controller_ops.window_alignment and shim
Add pci_controller_ops.window_alignment,
shadowing ppc_md.pcibios_window_alignment.
Add a shim, and changes the callsites to use the shim.

Here, we use pci_window_alignment, as pcibios_window_alignment is
already taken.

Signed-off-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-04-11 20:49:13 +10:00
Daniel Axtens
b31e79f8d9 powerpc: Create pci_controller_ops.enable_device_hook and shim
Add pci_controller_ops.enable_device_hook,
shadowing ppc_md.pcibios_enable_device_hook.
Add a shim, and changes the callsites to use the shim.

Signed-off-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-04-11 20:49:13 +10:00
Daniel Axtens
ff9df8c87d powerpc: Create pci_controller_ops.probe_mode and shim
Add pci_controller_ops.probe_mode, shadowing ppc_md.pci_probe_mode.
Add a shim, and changes the callsites to use the shim.

We also need to move the probe mode defines to pci-bridge.h from pci.h.
They are required by the shim in order to return a sensible default.
Previously, the were defined in pci.h, but pci.h includes pci-bridge.h
before the relevant #defines. This means the definitions are absent
if pci.h is included before pci-bridge.h. This occurs in some drivers.
So, move the definitons now, and move them back when we remove the shim.

Anything that wants the defines would have had to include pci.h, and
since pci.h includes pci-bridge.h, nothing will lose access to the
defines.

Signed-off-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-04-11 20:49:12 +10:00
Daniel Axtens
b122c95494 powerpc: Create pci_controller_ops.dma_bus_setup and shim
Add pci_controller_ops.dma_bus_setup, shadowing ppc_md.pci_dma_bus_setup.
Add a shim, and changes the callsites to use the shim.

Signed-off-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-04-11 20:49:11 +10:00
Daniel Axtens
e02def5bce powerpc: Create pci_controller_ops.dma_dev_setup and shim
Introduces the pci_controller_ops structure.
Add pci_controller_ops.dma_dev_setup, shadowing ppc_md.pci_dma_dev_setup.
Add a shim, and change the callsites to use the shim.

Signed-off-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-04-11 20:49:11 +10:00
Daniel Axtens
c88c2a1889 powerpc: pcibios_enable_device_hook: return bool rather than int
pcibios_enable_device_hook returned an int. Every implementation
returned either -EINVAL or 0. The return value wasn't propagated by
the caller: any non-zero return value caused pcibios_enable_device
to return -EINVAL itself. Therefore, make the hook return a bool.

Signed-off-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-04-11 20:49:10 +10:00
Daniel Axtens
bdc728a849 powerpc: move find_and_init_phbs() to pSeries specific code
Previously, find_and_init_phbs() was used in both PowerNV and pSeries
setup. However, since RTAS support has been dropped from PowerNV, we
can move it into a platform-specific file.

Signed-off-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-04-11 20:49:09 +10:00
Michael Ellerman
7e862d7e7d powerpc: Reword the "returning from prom_init" message
We get way too many bug reports that say "the kernel is hung in
prom_init", which stems from the fact that the last piece of output
people see is "returning from prom_init".

The kernel is almost never hung in prom_init(), it's just that it's
crashed somewhere after prom_init() but prior to the console coming up.

The existing message should give a clue to that, ie. "returning from"
indicates that prom_init() has finished, but it doesn't seem to work.
Let's try something different.

This prints:

  Quiescing Open Firmware ...
  Booting Linux via __start() ...

Which hopefully makes it clear that prom_init() is not the problem, and
although __start() probably isn't either, it's at least the right place
to begin looking.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Wistfully-Acked-by: Jeremy Kerr <jk@ozlabs.org>
2015-04-10 20:02:48 +10:00
Michael Ellerman
f691fa1080 powerpc: Replace mem_init_done with slab_is_available()
We have a powerpc specific global called mem_init_done which is "set on
boot once kmalloc can be called".

But that's not *quite* true. We set it at the bottom of mem_init(), and
rely on the fact that mm_init() calls kmem_cache_init() immediately
after that, and nothing is running in parallel.

So replace it with the generic and 100% correct slab_is_available().

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-04-10 20:02:48 +10:00
Michael Ellerman
bf4981a006 powerpc: Remove the celleb support
The celleb code has seen no actual development for ~7 years.

We (maintainers) have no access to test hardware, and it is highly
likely the code has bit-rotted.

As far as we're aware the hardware was never widely available, and is
certainly no longer available, and no one on the list has shown any
interest in it over the years.

So remove it. If anyone has one and cares please speak up.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Jeremy Kerr <jk@ozlabs.org>
2015-04-07 17:15:13 +10:00
Michael Ellerman
428d4d6520 Merge branch 'next-eeh' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc into next 2015-04-07 13:24:55 +10:00
Gavin Shan
433185d2b4 powerpc/eeh: Fix PE#0 check in eeh_add_to_parent_pe()
The function eeh_add_parent_pe() is used to create a PE or add one
edev to its parent PE. Current code checks if PE#0 is valid for the
later case. Actually, we should validate PE#0 for both cases when
EEH core regards PE#0 as invalid one (without flag EEH_VALID_PE_ZERO).
Otherwise, not all EEH devices can be added to its parent PE#0 for
EEH on P7IOC.

The patch fixes the issue by validating PE#0 for the two cases. So far,
we don't have PE#0 for EEH on P7IOC, but it will show up when we enable
M64 for P7IOC. The patch also makes the error message more meaningful.

Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2015-03-31 13:10:39 +11:00
Michael Ellerman
529d235a0e powerpc: Add a proper syscall for switching endianness
We currently have a "special" syscall for switching endianness. This is
syscall number 0x1ebe, which is handled explicitly in the 64-bit syscall
exception entry.

That has a few problems, firstly the syscall number is outside of the
usual range, which confuses various tools. For example strace doesn't
recognise the syscall at all.

Secondly it's handled explicitly as a special case in the syscall
exception entry, which is complicated enough without it.

As a first step toward removing the special syscall, we need to add a
regular syscall that implements the same functionality.

The logic is simple, it simply toggles the MSR_LE bit in the userspace
MSR. This is the same as the special syscall, with the caveat that the
special syscall clobbers fewer registers.

This version clobbers r9-r12, XER, CTR, and CR0-1,5-7.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-03-28 22:03:40 +11:00
Tyrel Datwyler
c03e73740d powerpc/pseries: Simplify check for suspendability during suspend/migration
During suspend/migration operation we must wait for the VASI state reported
by the hypervisor to become Suspending prior to making the ibm,suspend-me
RTAS call. Calling routines to rtas_ibm_supend_me() pass a vasi_state variable
that exposes the VASI state to the caller. This is unnecessary as the caller
only really cares about the following three conditions; if there is an error
we should bailout, success indicating we have suspended and woken back up so
proceed to device tree update, or we are not suspendable yet so try calling
rtas_ibm_suspend_me again shortly.

This patch removes the extraneous vasi_state variable and simply uses the
return code to communicate how to proceed. We either succeed, fail, or get
-EAGAIN in which case we sleep for a second before trying to call
rtas_ibm_suspend_me again. The behaviour of ppc_rtas() remains the same,
but migrate_store() now returns the propogated error code on failure.
Previously -1 was returned from migrate_store() in the  failure case which
equates to -EPERM and was clearly wrong.

Signed-off-by: Tyrel Datwyler <tyreld@linux.vnet.ibm.com>
Cc: Nathan Fontenont <nfont@linux.vnet.ibm.com>
Cc: Cyril Bur <cyrilbur@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-03-28 12:20:39 +11:00
Gavin Shan
c6406d8fbb powerpc/eeh: Remove device_node dependency
The patch removes struct eeh_dev::dn and the corresponding helper
functions: eeh_dev_to_of_node() and of_node_to_eeh_dev(). Instead,
eeh_dev_to_pdn() and pdn_to_eeh_dev() should be used to get the
pdn, which might contain device_node on PowerNV platform.

Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2015-03-24 13:15:53 +11:00
Gavin Shan
0bd785873c powerpc/eeh: Replace device_node with pci_dn in eeh_ops
There are 3 EEH operations whose arguments contain device_node:
read_config(), write_config() and restore_config(). The patch
replaces device_node with pci_dn.

Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2015-03-24 13:15:52 +11:00
Gavin Shan
ff57b454dd powerpc/eeh: Do probe on pci_dn
Originally, EEH core probes on device_node or pci_dev to populate
EEH devices and PEs, which conflicts with the fact: SRIOV VFs are
usually enabled and created by PF's driver and they don't have the
corresponding device_nodes. Instead, SRIOV VFs have dynamically
created pci_dn, which can be used for EEH probe.

The patch reworks EEH probe for PowerNV and pSeries platforms to
do probing based on pci_dn, instead of pci_dev or device_node any
more.

Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2015-03-24 13:15:52 +11:00
Gavin Shan
e8e9b34cef powerpc/eeh: Create eeh_dev from pci_dn instead of device_node
The patch adds function traverse_pci_dn(), which is similar to
traverse_pci_devices() except it takes pci_dn, not device_node
as parameter. The pci_dev.c has been reworked to create eeh_dev
from pci_dn, instead of device_node.

Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2015-03-24 13:15:51 +11:00
Gavin Shan
c035ff1d2e powerpc/pci: Trace more information from pci_dn
Originally, EEH probes on device_node or pci_dev and populates the
corresponding eeh_dev. In the subsequent patches, EEH will probes
on pci_dn and populates the corresponding eeh_dev. So we have to
cache some information in pci_dn, either from device_node or SRIOV
PF's enablement platform hook, to populate the eeh_dev properly.

The motivation to probe pci_dn, instead of device node or pci_dev,
to populate eeh_dev is SRIOV VFs are dynamically created and we
don't have the corresponding device nodes for them.

Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2015-03-24 13:15:50 +11:00
Gavin Shan
cca87d303c powerpc/pci: Refactor pci_dn
Currently, the PCI config accessors are implemented based on device node.
Unfortunately, SRIOV VFs won't have the corresponding device nodes. pci_dn
will be used in replacement with device node for SRIOV VFs. So we have to
use pci_dn in PCI config accessors.

The patch refactors pci_dn in following aspects to make it ready to be used
in PCI config accessors as we do in subsequent patch:

   * pci_dn is organized as a hierarchy tree.  PCI device's pci_dn is
     put to the child list of pci_dn of its upstream bridge or PHB. VF's
     pci_dn will be put to the child list of pci_dn of PF's bridge.

   * For one particular PCI device (VF or not), its pci_dn can be
     found from pdev->dev.archdata.pci_data, PCI_DN(devnode), or
     parent's list.  The fast path (fetching pci_dn through PCI device
     instance) is populated during early fixup time.

[bhelgaas: changelog]
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2015-03-24 13:15:49 +11:00
Paul Mackerras
f57333a767 powerpc/powernv: Fix return value from power7_nap() et al.
The power7_nap(), power7_sleep() and power7_winkle() functions are
called from pnv_smp_cpu_kill_self(), which expects them to return the
SRR1 value set by the hardware on wakeup, or 0 if no nap/sleep/winkle
occurred.  However, in the case where an interrupt needs to be
replayed, the logic in power7_powersave_common (the common code for
power7_nap et al.) doesn't set r3 to 0 in this case.  Instead what we
get as the return value is the selector for the type of power-saving
mode requested (1, 2 or 3).  In fact this should not affect the
operation of pnv_smp_cpu_kill_self(), but it is better to get this
correct, so this adds an instruction to set r3 to 0 in this case.

Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-03-23 15:06:50 +11:00
Hari Bathini
e4a9616c54 powerpc/rtas: Make timestamp related code y2038-safe
While we are here, let us make timestamp related code y2038-safe.

Suggested-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Hari Bathini <hbathini@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-03-23 14:06:11 +11:00
Hari Bathini
f7618299b4 powerpc/powernv: Add pstore support on powernv
This patch extends pstore, a generic interface to platform dependent
persistent storage, support for powernv  platform to capture certain
useful information, during dying moments. Such support is already in
place for  pseries platform. This patch re-uses most of that code.

It is a common practice to compile kernels with both CONFIG_PPC_PSERIES=y
and CONFIG_PPC_POWERNV=y. The code in nvram_init_oops_partition() routine
still works as intended, as the caller is platform specific code which
passes the appropriate value for "rtas_partition_exists" parameter.
In all other places, where CONFIG_PPC_PSERIES or CONFIG_PPC_POWERNV
flag is used in this patchset, it is to reduce the kernel size in cases
where this flag is not set and doesn't have any impact logic wise.

Signed-off-by: Hari Bathini <hbathini@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-03-23 14:06:10 +11:00
Hari Bathini
78989f0a55 powerpc/nvram: Move generic code for nvram and pstore
With minor checks, we can move most of the code for nvram
under pseries to a common place to be re-used by other
powerpc platforms like powernv. This patch moves such
common code to arch/powerpc/kernel/nvram_64.c file.

Signed-off-by: Hari Bathini <hbathini@linux.vnet.ibm.com>
[mpe: Move select of ZLIB_DEFLATE to PPC64 to fix the build]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-03-23 14:05:49 +11:00
Alex Dowad
6eca8933d3 powerpc/kernel: Rename copy_thread() 'arg' argument to 'kthread_arg'
The 'arg' argument to copy_thread() is only ever used when forking a new
kernel thread. Hence, rename it to 'kthread_arg' for clarity.

Signed-off-by: Alex Dowad <alexinbeijing@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-03-20 12:41:15 +11:00
Kevin Hao
52d9962700 powerpc: kill PPC_OF
We have set CONFIG_PPC_OF to always 'y' in commit 0a498d96a3
("powerpc: set CONFIG_PPC_OF=y always for ARCH=powerpc") nine years
ago. And the arch/ppc also has gone away for many years. The OF
functionality was also moved to a common place and be used by many
archs. So it does make no sense to keep such a option in the current
kernel. Just kill it.

Signed-off-by: Kevin Hao <haokexin@gmail.com>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-03-17 20:04:32 +11:00
Gavin Shan
28158cd1b7 powerpc/eeh: Enhance pcibios_set_pcie_reset_state()
Function pcibios_set_pcie_reset_state() is possibly called by
pci_reset_function(), on which VFIO infrastructure depends to
issue reset. pcibios_set_pcie_reset_state() is issuing reset
on the parent PE of the indicated PCI device. The reset causes
state lost on all PCI devices except the indicated one as the
argument to pcibios_set_pcie_reset_state(). Also, sideband
MMIO access from guest when issuing reset would cause unexpected
EEH error.

For above two issues, the patch applies following enhancements
to pcibios_set_pcie_reset_state():

   * For all PCI devices except the indicated one, save their
     state prior to reset and restore state after that.
   * Explicitly freeze PE prior to reset and unfreeze it after
     that, in order to avoid unexpected EEH error.

Tested-by: Priya M. A <priyama2@in.ibm.com>
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2015-03-17 10:31:18 +11:00
Mahesh Salgaonkar
45706bb53d powerpc/book3s: Fix flush_tlb cpu_spec hook to take a generic argument.
The flush_tlb hook in cpu_spec was introduced as a generic function hook
to invalidate TLBs. But the current implementation of flush_tlb hook
takes IS (invalidation selector) as an argument which is architecture
dependent. Hence, It is not right to have a generic routine where caller
has to pass non-generic argument.

This patch fixes this and makes flush_tlb hook as high level API.

Reported-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-03-17 07:52:48 +11:00
Anton Blanchard
c2ce6f9f3d powerpc: Change vrX register defines to vX to match gcc and glibc
As our various loops (copy, string, crypto etc) get more complicated,
we want to share implementations between userspace (eg glibc) and
the kernel. We also want to write userspace test harnesses to put
in tools/testing/selftest.

One gratuitous difference between userspace and the kernel is the
VMX register definitions - the kernel uses vrX whereas both gcc and
glibc use vX.

Change the kernel to match userspace.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-03-16 18:32:11 +11:00
Nishanth Aravamudan
4ad04e5987 powerpc/iommu: Remove IOMMU device references via bus notifier
After d905c5df9a ("PPC: POWERNV: move iommu_add_device earlier"), the
refcnt on the kobject backing the IOMMU group for a PCI device is
elevated by each call to pci_dma_dev_setup_pSeriesLP() (via
set_iommu_table_base_and_group). When we go to dlpar a multi-function
PCI device out:

        iommu_reconfig_notifier ->
                iommu_free_table ->
                        iommu_group_put
                        BUG_ON(tbl->it_group)

We trip this BUG_ON, because there are still references on the table, so
it is not freed. Fix this by moving the powernv bus notifier to common
code and calling it for both powernv and pseries.

Fixes: d905c5df9a ("PPC: POWERNV: move iommu_add_device earlier")
Signed-off-by: Nishanth Aravamudan <nacc@linux.vnet.ibm.com>
Tested-by: Nishanth Aravamudan <nacc@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-03-04 13:19:33 +11:00
Michael Ellerman
875ebe940d powerpc/smp: Wait until secondaries are active & online
Anton has a busy ppc64le KVM box where guests sometimes hit the infamous
"kernel BUG at kernel/smpboot.c:134!" issue during boot:

  BUG_ON(td->cpu != smp_processor_id());

Basically a per CPU hotplug thread scheduled on the wrong CPU. The oops
output confirms it:

  CPU: 0
  Comm: watchdog/130

The problem is that we aren't ensuring the CPU active bit is set for the
secondary before allowing the master to continue on. The master unparks
the secondary CPU's kthreads and the scheduler looks for a CPU to run
on. It calls select_task_rq() and realises the suggested CPU is not in
the cpus_allowed mask. It then ends up in select_fallback_rq(), and
since the active bit isnt't set we choose some other CPU to run on.

This seems to have been introduced by 6acbfb9697 "sched: Fix hotplug
vs. set_cpus_allowed_ptr()", which changed from setting active before
online to setting active after online. However that was in turn fixing a
bug where other code assumed an active CPU was also online, so we can't
just revert that fix.

The simplest fix is just to spin waiting for both active & online to be
set. We already have a barrier prior to set_cpu_online() (which also
sets active), to ensure all other setup is completed before online &
active are set.

Fixes: 6acbfb9697 ("sched: Fix hotplug vs. set_cpus_allowed_ptr()")
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-03-04 13:19:33 +11:00
Linus Torvalds
18a8d49973 The clock framework changes for 3.20 contain the usual driver additions,
enhancements and fixes mostly for ARM32, ARM64, MIPS and Power-based
 devices. Additionaly the framework core underwent a bit of surgery with
 two major changes. The boundary between the clock core and clock
 providers (e.g clock drivers) is now more well defined with dedicated
 provider helper functions. struct clk no longer maps 1:1 with the
 hardware clock but is a true per-user cookie which helps us tracker
 users of hardware clocks and debug bad behavior. The second major change
 is the addition of rate constraints for clocks. Rate ranges are now
 supported which are analogous to the voltage ranges in the regulator
 framework. Unfortunately these changes to the core created some
 breakeage. We think we fixed it all up but for this reason there are
 lots of last minute commits trying to undo the damage.
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Merge tag 'clk-for-linus-3.20' of git://git.linaro.org/people/mike.turquette/linux

Pull clock framework updates from Mike Turquette:
 "The clock framework changes contain the usual driver additions,
  enhancements and fixes mostly for ARM32, ARM64, MIPS and Power-based
  devices.

  Additionally the framework core underwent a bit of surgery with two
  major changes:

   - The boundary between the clock core and clock providers (e.g clock
     drivers) is now more well defined with dedicated provider helper
     functions.  struct clk no longer maps 1:1 with the hardware clock
     but is a true per-user cookie which helps us tracker users of
     hardware clocks and debug bad behavior.

   - The addition of rate constraints for clocks.  Rate ranges are now
     supported which are analogous to the voltage ranges in the
     regulator framework.

  Unfortunately these changes to the core created some breakeage.  We
  think we fixed it all up but for this reason there are lots of last
  minute commits trying to undo the damage"

* tag 'clk-for-linus-3.20' of git://git.linaro.org/people/mike.turquette/linux: (113 commits)
  clk: Only recalculate the rate if needed
  Revert "clk: mxs: Fix invalid 32-bit access to frac registers"
  clk: qoriq: Add support for the platform PLL
  powerpc/corenet: Enable CLK_QORIQ
  clk: Replace explicit clk assignment with __clk_hw_set_clk
  clk: Add __clk_hw_set_clk helper function
  clk: Don't dereference parent clock if is NULL
  MIPS: Alchemy: Remove bogus args from alchemy_clk_fgcs_detr
  clkdev: Always allocate a struct clk and call __clk_get() w/ CCF
  clk: shmobile: div6: Avoid division by zero in .round_rate()
  clk: mxs: Fix invalid 32-bit access to frac registers
  clk: omap: compile legacy omap3 clocks conditionally
  clkdev: Export clk_register_clkdev
  clk: Add rate constraints to clocks
  clk: remove clk-private.h
  pci: xgene: do not use clk-private.h
  arm: omap2+ remove dead clock code
  clk: Make clk API return per-user struct clk instances
  clk: tegra: Define PLLD_DSI and remove dsia(b)_mux
  clk: tegra: Add support for the Tegra132 CAR IP block
  ...
2015-02-21 12:30:30 -08:00
Geoff Levand
b28c2ee868 kexec: add IND_FLAGS macro
Add a new kexec preprocessor macro IND_FLAGS, which is the bitwise OR of
all the possible kexec IND_ kimage_entry indirection flags.  Having this
macro allows for simplified code in the prosessing of the kexec
kimage_entry items.  Also, remove the local powerpc definition and use the
generic one.

Signed-off-by: Geoff Levand <geoff@infradead.org>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Maximilian Attems <max@stro.at>
Cc: Michal Marek <mmarek@suse.cz>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Paul Bolle <pebolle@tiscali.nl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-02-17 14:34:51 -08:00
Tejun Heo
0c118b7bd0 powerpc: use %*pb[l] to print bitmaps including cpumasks and nodemasks
printk and friends can now format bitmaps using '%*pb[l]'.  cpumask
and nodemask also provide cpumask_pr_args() and nodemask_pr_args()
respectively which can be used to generate the two printf arguments
necessary to format the specified cpu/nodemask.

* Spurious if (len > 1) test dropped from shared_cpu_map_show().

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-02-13 21:21:36 -08:00
Cyril Bur
4be1b29795 powerpc: add running_clock for powerpc to prevent spurious softlockup warnings
On POWER8 virtualised kernels the VTB register can be read to have a view
of time that only increases while the guest is running.  This will prevent
guests from seeing time jump if a guest is paused for significant amounts
of time.

On POWER7 and below virtualised kernels stolen time is subtracted from
local_clock as a best effort approximation.  This will not eliminate
spurious warnings in the case of a suspended guest but may reduce the
occurance in the case of softlockups due to host over commit.

Bare metal kernels should avoid reading the VTB as KVM does not restore
sane values when not executing, the approxmation is fine as host kernels
won't observe any stolen time.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Cyril Bur <cyrilbur@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Andrew Jones <drjones@redhat.com>
Acked-by: Don Zickus <dzickus@redhat.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Ulrich Obergfell <uobergfe@redhat.com>
Cc: chai wen <chaiw.fnst@cn.fujitsu.com>
Cc: Fabian Frederick <fabf@skynet.be>
Cc: Aaron Tomlin <atomlin@redhat.com>
Cc: Ben Zhang <benzh@chromium.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-02-12 18:54:13 -08:00
Andy Lutomirski
f56141e3e2 all arches, signal: move restart_block to struct task_struct
If an attacker can cause a controlled kernel stack overflow, overwriting
the restart block is a very juicy exploit target.  This is because the
restart_block is held in the same memory allocation as the kernel stack.

Moving the restart block to struct task_struct prevents this exploit by
making the restart_block harder to locate.

Note that there are other fields in thread_info that are also easy
targets, at least on some architectures.

It's also a decent simplification, since the restart code is more or less
identical on all architectures.

[james.hogan@imgtec.com: metag: align thread_info::supervisor_stack]
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: David Miller <davem@davemloft.net>
Acked-by: Richard Weinberger <richard@nod.at>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Haavard Skinnemoen <hskinnemoen@gmail.com>
Cc: Hans-Christian Egtvedt <egtvedt@samfundet.no>
Cc: Steven Miao <realmz6@gmail.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: Aurelien Jacquiot <a-jacquiot@ti.com>
Cc: Mikael Starvik <starvik@axis.com>
Cc: Jesper Nilsson <jesper.nilsson@axis.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Richard Kuo <rkuo@codeaurora.org>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: Helge Deller <deller@gmx.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Tested-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Chen Liqin <liqin.linux@gmail.com>
Cc: Lennox Wu <lennox.wu@gmail.com>
Cc: Chris Metcalf <cmetcalf@ezchip.com>
Cc: Guan Xuetao <gxt@mprc.pku.edu.cn>
Cc: Chris Zankel <chris@zankel.net>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-02-12 18:54:12 -08:00
Linus Torvalds
d3f180ea1a powerpc updates for 3.20
Including:
 
 - Update of all defconfigs
 - Addition of a bunch of config options to modernise our defconfigs
 - Some PS3 updates from Geoff
 - Optimised memcmp for 64 bit from Anton
 - Fix for kprobes that allows 'perf probe' to work from Naveen
 - Several cxl updates from Ian & Ryan
 - Expanded support for the '24x7' PMU from Cody & Sukadev
 - Freescale updates from Scott:
   "Highlights include 8xx optimizations, some more work on datapath device
    tree content, e300 machine check support, t1040 corenet error reporting,
    and various cleanups and fixes."
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Merge tag 'powerpc-3.20-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mpe/linux

Pull powerpc updates from Michael Ellerman:

 - Update of all defconfigs

 - Addition of a bunch of config options to modernise our defconfigs

 - Some PS3 updates from Geoff

 - Optimised memcmp for 64 bit from Anton

 - Fix for kprobes that allows 'perf probe' to work from Naveen

 - Several cxl updates from Ian & Ryan

 - Expanded support for the '24x7' PMU from Cody & Sukadev

 - Freescale updates from Scott:
    "Highlights include 8xx optimizations, some more work on datapath
     device tree content, e300 machine check support, t1040 corenet
     error reporting, and various cleanups and fixes"

* tag 'powerpc-3.20-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mpe/linux: (102 commits)
  cxl: Add missing return statement after handling AFU errror
  cxl: Fail AFU initialisation if an invalid configuration record is found
  cxl: Export optional AFU configuration record in sysfs
  powerpc/mm: Warn on flushing tlb page in kernel context
  powerpc/powernv: Add OPAL soft-poweroff routine
  powerpc/perf/hv-24x7: Document sysfs event description entries
  powerpc/perf/hv-gpci: add the remaining gpci requests
  powerpc/perf/{hv-gpci, hv-common}: generate requests with counters annotated
  powerpc/perf/hv-24x7: parse catalog and populate sysfs with events
  perf: define EVENT_DEFINE_RANGE_FORMAT_LITE helper
  perf: add PMU_EVENT_ATTR_STRING() helper
  perf: provide sysfs_show for struct perf_pmu_events_attr
  powerpc/kernel: Avoid initializing device-tree pointer twice
  powerpc: Remove old compile time disabled syscall tracing code
  powerpc/kernel: Make syscall_exit a local label
  cxl: Fix device_node reference counting
  powerpc/mm: bail out early when flushing TLB page
  powerpc: defconfigs: add MTD_SPI_NOR (new dependency for M25P80)
  perf/powerpc: reset event hw state when adding it to the PMU
  powerpc/qe: Use strlcpy()
  ...
2015-02-11 18:15:38 -08:00
Michael Ellerman
a604c96eb0 Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/scottwood/linux into next
Freescale updates from Scott:

"Highlights include 8xx optimizations, some more work on datapath device
tree content, e300 machine check support, t1040 corenet error reporting,
and various cleanups and fixes."
2015-02-04 12:03:21 +11:00
Michael Turquette
54eea32f7e Merge branch 'clk-next' into v3.19-rc7 2015-02-02 14:59:38 -08:00
Gavin Shan
fe12545e76 powerpc/kernel: Avoid initializing device-tree pointer twice
As commit 50ba08f3 ("of/fdt: Don't clear initial_boot_params
if fdt_check_header() fails") does, the device-tree pointer
"initial_boot_params" is initialized by early_init_dt_verify(),
which is called by early_init_devtree(). So we needn't explicitly
initialize that again in early_init_devtree().

Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-02-02 14:51:32 +11:00
Michael Ellerman
a4bcbe6a41 powerpc: Remove old compile time disabled syscall tracing code
We have code to do syscall tracing which is disabled at compile time by
default. It's not been touched since the dawn of time (ie. v2.6.12).

There are now better ways to do syscall tracing, ie. using the
raw_syscall, or syscall tracepoints.

For the specific case of tracing syscalls at boot on a system that
doesn't get to userspace, you can boot with:

  trace_event=syscalls tp_printk=on

Which will trace syscalls from boot, and echo all output to the console.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-02-02 14:51:32 +11:00
Michael Ellerman
4c3b216861 powerpc/kernel: Make syscall_exit a local label
Currently when we back trace something that is in a syscall we see
something like this:

[c000000000000000] [c000000000000000] SyS_read+0x6c/0x110
[c000000000000000] [c000000000000000] syscall_exit+0x0/0x98

Although it's entirely correct, seeing syscall_exit at the bottom can be
confusing - we were exiting from a syscall and then called SyS_read() ?

If we instead change syscall_exit to be a local label we get something
more intuitive:

[c0000001fa46fde0] [c00000000026719c] SyS_read+0x6c/0x110
[c0000001fa46fe30] [c000000000009264] system_call+0x38/0xd0

ie. we were handling a system call, and it was SyS_read().

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-02-02 14:51:31 +11:00
Esben Haabendal
974ff4e2d7 powerpc: Add machine_check cpu function for e300c3 cpus
Signed-off-by: Esben Haabendal <eha@deif.com>
Signed-off-by: Scott Wood <scottwood@freescale.com>
2015-01-29 22:57:40 -06:00
LEROY Christophe
4545ff7ed8 powerpc/8xx: Remove duplicated code in set_context()
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Scott Wood <scottwood@freescale.com>
2015-01-29 21:59:02 -06:00
LEROY Christophe
fde5a9057f powerpc/8xx: Optimise access to swapper_pg_dir
All accessed to PGD entries are done via 0(r11).
By using lower part of swapper_pg_dir as load index to r11, we can remove the
ori instruction.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Scott Wood <scottwood@freescale.com>
2015-01-29 21:59:02 -06:00