Commit graph

36 commits

Author SHA1 Message Date
Frederic Barrat
748ac391ab pci/hotplug/pnv-php: Wrap warnings in macro
An opencapi slot doesn't have an associated bridge device. It's not
needed for operation, but any warning is displayed through pci_warn()
which uses the pci_dev struct of the assocated bridge device. So wrap
those warning so that a different trace mechanism can be used if it's
an opencapi slot.

Reviewed-by: Alastair D'Silva <alastair@d-silva.org>
Reviewed-by: Andrew Donnellan <ajd@linux.ibm.com>
Signed-off-by: Frederic Barrat <fbarrat@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20191121134918.7155-11-fbarrat@linux.ibm.com
2020-01-23 21:31:17 +11:00
Frederic Barrat
be1611e043 pci/hotplug/pnv-php: Relax check when disabling slot
The driver only allows to disable a slot in the POPULATED
state. However, if an error occurs while enabling the slot, say
because the link couldn't be trained, then the POPULATED state may not
be reached, yet the power state of the slot is on. So allow to disable
a slot in the REGISTERED state. Removing the devices will do nothing
since it's not populated, and we'll set the power state of the slot
back to off.

Reviewed-by: Alastair D'Silva <alastair@d-silva.org>
Reviewed-by: Andrew Donnellan <ajd@linux.ibm.com>
Signed-off-by: Frederic Barrat <fbarrat@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20191121134918.7155-10-fbarrat@linux.ibm.com
2020-01-23 21:31:17 +11:00
Frederic Barrat
ea53919b15 pci/hotplug/pnv-php: Register opencapi slots
Add the opencapi PHBs to the list of PHBs being scanned to look for
slots.

Signed-off-by: Frederic Barrat <fbarrat@linux.ibm.com>
Reviewed-by: Andrew Donnellan <ajd@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20191121134918.7155-9-fbarrat@linux.ibm.com
2020-01-23 21:31:17 +11:00
Frederic Barrat
323c2a26ff pci/hotplug/pnv-php: Improve error msg on power state change failure
When changing the slot state, if opal hits an error and tells as such
in the asynchronous reply, the warning "Wrong msg" is logged, which is
rather confusing. Instead we can reuse the better message which is
already used when we couldn't submit the asynchronous opal request
initially.

Reviewed-by: Alastair D'Silva <alastair@d-silva.org>
Reviewed-by: Andrew Donnellan <ajd@linux.ibm.com>
Signed-off-by: Frederic Barrat <fbarrat@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20191121134918.7155-8-fbarrat@linux.ibm.com
2020-01-23 21:31:17 +11:00
Frederic Barrat
658ab186dd pci/hotplug/pnv-php: Remove erroneous warning
On powernv, when removing a device through hotplug, the following
warning is logged:

     Invalid refcount <.> on <...>

It may be incorrect, the refcount may be set to a higher value than 1
and be valid. of_detach_node() can drop more than one reference. As it
doesn't seem trivial to assert the correct value, let's remove the
warning.

Reviewed-by: Alastair D'Silva <alastair@d-silva.org>
Reviewed-by: Andrew Donnellan <ajd@linux.ibm.com>
Signed-off-by: Frederic Barrat <fbarrat@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20191121134918.7155-7-fbarrat@linux.ibm.com
2020-01-23 21:31:17 +11:00
Oliver O'Halloran
018c49e999 pci-hotplug/pnv_php: Add attention indicator support
pnv_php is generally used with PCIe bridges which provide a native
interface for setting the attention and power indicator LEDs. Wire up
those interfaces even if firmware does not have support for them (yet...)

Signed-off-by: Oliver O'Halloran <oohall@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190903101605.2890-11-oohall@gmail.com
2019-09-05 14:22:39 +10:00
Oliver O'Halloran
a839bd87a2 pci-hotplug/pnv_php: Add support for IODA3 Power9 PHBs
Currently we check that an IODA2 compatible PHB is upstream of this slot.
This is mainly to avoid pnv_php creating slots for the various "virtual
PHBs" that we create for NVLink. There's no real need for this restriction
so allow it on IODA3.

Signed-off-by: Oliver O'Halloran <oohall@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190903101605.2890-10-oohall@gmail.com
2019-09-05 14:22:39 +10:00
Oliver O'Halloran
7fd1fe4e48 pci-hotplug/pnv_php: Add a reset_slot() callback
When performing EEH recovery of devices in a hotplug slot we need to use
the slot driver's ->reset_slot() callback to prevent spurious hotplug
events due to spurious DLActive and PresDet change interrupts. Add a
reset_slot() callback to pnv_php so we can handle recovery of devices
in pnv_php managed slots.

Signed-off-by: Oliver O'Halloran <oohall@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190903101605.2890-9-oohall@gmail.com
2019-09-05 14:22:39 +10:00
Linus Torvalds
685f7e4f16 powerpc updates for 4.20
Notable changes:
 
  - A large series to rewrite our SLB miss handling, replacing a lot of fairly
    complicated asm with much fewer lines of C.
 
  - Following on from that, we now maintain a cache of SLB entries for each
    process and preload them on context switch. Leading to a 27% speedup for our
    context switch benchmark on Power9.
 
  - Improvements to our handling of SLB multi-hit errors. We now print more debug
    information when they occur, and try to continue running by flushing the SLB
    and reloading, rather than treating them as fatal.
 
  - Enable THP migration on 64-bit Book3S machines (eg. Power7/8/9).
 
  - Add support for physical memory up to 2PB in the linear mapping on 64-bit
    Book3S. We only support up to 512TB as regular system memory, otherwise the
    percpu allocator runs out of vmalloc space.
 
  - Add stack protector support for 32 and 64-bit, with a per-task canary.
 
  - Add support for PTRACE_SYSEMU and PTRACE_SYSEMU_SINGLESTEP.
 
  - Support recognising "big cores" on Power9, where two SMT4 cores are presented
    to us as a single SMT8 core.
 
  - A large series to cleanup some of our ioremap handling and PTE flags.
 
  - Add a driver for the PAPR SCM (storage class memory) interface, allowing
    guests to operate on SCM devices (acked by Dan).
 
  - Changes to our ftrace code to handle very large kernels, where we need to use
    a trampoline to get to ftrace_caller().
 
 Many other smaller enhancements and cleanups.
 
 Thanks to:
   Alan Modra, Alistair Popple, Aneesh Kumar K.V, Anton Blanchard, Aravinda
   Prasad, Bartlomiej Zolnierkiewicz, Benjamin Herrenschmidt, Breno Leitao,
   Cédric Le Goater, Christophe Leroy, Christophe Lombard, Dan Carpenter, Daniel
   Axtens, Finn Thain, Gautham R. Shenoy, Gustavo Romero, Haren Myneni, Hari
   Bathini, Jia Hongtao, Joel Stanley, John Allen, Laurent Dufour, Madhavan
   Srinivasan, Mahesh Salgaonkar, Mark Hairgrove, Masahiro Yamada, Michael
   Bringmann, Michael Neuling, Michal Suchanek, Murilo Opsfelder Araujo, Nathan
   Fontenot, Naveen N. Rao, Nicholas Piggin, Nick Desaulniers, Oliver O'Halloran,
   Paul Mackerras, Petr Vorel, Rashmica Gupta, Reza Arbab, Rob Herring, Sam
   Bobroff, Samuel Mendoza-Jonas, Scott Wood, Stan Johnson, Stephen Rothwell,
   Stewart Smith, Suraj Jitindar Singh, Tyrel Datwyler, Vaibhav Jain, Vasant
   Hegde, YueHaibing, zhong jiang,
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Merge tag 'powerpc-4.20-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc updates from Michael Ellerman:
 "Notable changes:

   - A large series to rewrite our SLB miss handling, replacing a lot of
     fairly complicated asm with much fewer lines of C.

   - Following on from that, we now maintain a cache of SLB entries for
     each process and preload them on context switch. Leading to a 27%
     speedup for our context switch benchmark on Power9.

   - Improvements to our handling of SLB multi-hit errors. We now print
     more debug information when they occur, and try to continue running
     by flushing the SLB and reloading, rather than treating them as
     fatal.

   - Enable THP migration on 64-bit Book3S machines (eg. Power7/8/9).

   - Add support for physical memory up to 2PB in the linear mapping on
     64-bit Book3S. We only support up to 512TB as regular system
     memory, otherwise the percpu allocator runs out of vmalloc space.

   - Add stack protector support for 32 and 64-bit, with a per-task
     canary.

   - Add support for PTRACE_SYSEMU and PTRACE_SYSEMU_SINGLESTEP.

   - Support recognising "big cores" on Power9, where two SMT4 cores are
     presented to us as a single SMT8 core.

   - A large series to cleanup some of our ioremap handling and PTE
     flags.

   - Add a driver for the PAPR SCM (storage class memory) interface,
     allowing guests to operate on SCM devices (acked by Dan).

   - Changes to our ftrace code to handle very large kernels, where we
     need to use a trampoline to get to ftrace_caller().

  And many other smaller enhancements and cleanups.

  Thanks to: Alan Modra, Alistair Popple, Aneesh Kumar K.V, Anton
  Blanchard, Aravinda Prasad, Bartlomiej Zolnierkiewicz, Benjamin
  Herrenschmidt, Breno Leitao, Cédric Le Goater, Christophe Leroy,
  Christophe Lombard, Dan Carpenter, Daniel Axtens, Finn Thain, Gautham
  R. Shenoy, Gustavo Romero, Haren Myneni, Hari Bathini, Jia Hongtao,
  Joel Stanley, John Allen, Laurent Dufour, Madhavan Srinivasan, Mahesh
  Salgaonkar, Mark Hairgrove, Masahiro Yamada, Michael Bringmann,
  Michael Neuling, Michal Suchanek, Murilo Opsfelder Araujo, Nathan
  Fontenot, Naveen N. Rao, Nicholas Piggin, Nick Desaulniers, Oliver
  O'Halloran, Paul Mackerras, Petr Vorel, Rashmica Gupta, Reza Arbab,
  Rob Herring, Sam Bobroff, Samuel Mendoza-Jonas, Scott Wood, Stan
  Johnson, Stephen Rothwell, Stewart Smith, Suraj Jitindar Singh, Tyrel
  Datwyler, Vaibhav Jain, Vasant Hegde, YueHaibing, zhong jiang"

* tag 'powerpc-4.20-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (221 commits)
  Revert "selftests/powerpc: Fix out-of-tree build errors"
  powerpc/msi: Fix compile error on mpc83xx
  powerpc: Fix stack protector crashes on CPU hotplug
  powerpc/traps: restore recoverability of machine_check interrupts
  powerpc/64/module: REL32 relocation range check
  powerpc/64s/radix: Fix radix__flush_tlb_collapsed_pmd double flushing pmd
  selftests/powerpc: Add a test of wild bctr
  powerpc/mm: Fix page table dump to work on Radix
  powerpc/mm/radix: Display if mappings are exec or not
  powerpc/mm/radix: Simplify split mapping logic
  powerpc/mm/radix: Remove the retry in the split mapping logic
  powerpc/mm/radix: Fix small page at boundary when splitting
  powerpc/mm/radix: Fix overuse of small pages in splitting logic
  powerpc/mm/radix: Fix off-by-one in split mapping logic
  powerpc/ftrace: Handle large kernel configs
  powerpc/mm: Fix WARN_ON with THP NUMA migration
  selftests/powerpc: Fix out-of-tree build errors
  powerpc/time: no steal_time when CONFIG_PPC_SPLPAR is not selected
  powerpc/time: Only set CONFIG_ARCH_HAS_SCALED_CPUTIME on PPC64
  powerpc/time: isolate scaled cputime accounting in dedicated functions.
  ...
2018-10-26 14:36:21 -07:00
Sam Bobroff
e762bb891a powerpc/eeh: Cleanup eeh_pe_state_mark()
Currently, eeh_pe_state_mark() marks a PE (and it's children) with a
state and then performs additional processing if that state included
EEH_PE_ISOLATED.

The state parameter is always a constant at the call site, so
rearrange eeh_pe_state_mark() into two functions and just call the
appropriate one at each site.

Signed-off-by: Sam Bobroff <sbobroff@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-10-13 22:21:25 +11:00
YueHaibing
74171e9dab PCI: pnv_php: Use kmemdup()
Use kmemdup() rather than duplicating its implementation.

Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
2018-10-02 16:04:40 -05:00
Lukas Wunner
125450f814 PCI: hotplug: Embed hotplug_slot
When the PCI hotplug core and its first user, cpqphp, were introduced in
February 2002 with historic commit a8a2069f432c, cpqphp allocated a slot
struct for its internal use plus a hotplug_slot struct to be registered
with the hotplug core and linked the two with pointers:
https://git.kernel.org/tglx/history/c/a8a2069f432c

Nowadays, the predominant pattern in the tree is to embed ("subclass")
such structures in one another and cast to the containing struct with
container_of().  But it wasn't until July 2002 that container_of() was
introduced with historic commit ec4f214232cf:
https://git.kernel.org/tglx/history/c/ec4f214232cf

pnv_php, introduced in 2016, did the right thing and embedded struct
hotplug_slot in its internal struct pnv_php_slot, but all other drivers
cargo-culted cpqphp's design and linked separate structs with pointers.

Embedding structs is preferrable to linking them with pointers because
it requires fewer allocations, thereby reducing overhead and simplifying
error paths.  Casting an embedded struct to the containing struct
becomes a cheap subtraction rather than a dereference.  And having fewer
pointers reduces the risk of them pointing nowhere either accidentally
or due to an attack.

Convert all drivers to embed struct hotplug_slot in their internal slot
struct.  The "private" pointer in struct hotplug_slot thereby becomes
unused, so drop it.

Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Tyrel Datwyler <tyreld@linux.vnet.ibm.com>  # drivers/pci/hotplug/rpa*
Acked-by: Sebastian Ott <sebott@linux.ibm.com>        # drivers/pci/hotplug/s390*
Acked-by: Andy Shevchenko <andy.shevchenko@gmail.com> # drivers/platform/x86
Cc: Len Brown <lenb@kernel.org>
Cc: Scott Murray <scott@spiteful.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Oliver OHalloran <oliveroh@au1.ibm.com>
Cc: Gavin Shan <gwshan@linux.vnet.ibm.com>
Cc: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Cc: Corentin Chary <corentin.chary@gmail.com>
Cc: Darren Hart <dvhart@infradead.org>
2018-09-18 17:52:15 -05:00
Lukas Wunner
a7da21613c PCI: hotplug: Drop hotplug_slot_info
Ever since the PCI hotplug core was introduced in 2002, drivers had to
allocate and register a struct hotplug_slot_info for every slot:
https://git.kernel.org/tglx/history/c/a8a2069f432c

Apparently the idea was that drivers furnish the hotplug core with an
up-to-date card presence status, power status, latch status and
attention indicator status as well as notify the hotplug core of changes
thereof.  However only 4 out of 12 hotplug drivers bother to notify the
hotplug core with pci_hp_change_slot_info() and the hotplug core never
made any use of the information:  There is just a single macro in
pci_hotplug_core.c, GET_STATUS(), which uses the hotplug_slot_info if
the driver lacks the corresponding callback in hotplug_slot_ops.  The
macro is called when the user reads the attribute via sysfs.

Now, if the callback isn't defined, the attribute isn't exposed in sysfs
in the first place (see e.g. has_power_file()).  There are only two
situations when the hotplug_slot_info would actually be accessed:

* If the driver defines ->enable_slot or ->disable_slot but not
  ->get_power_status.

* If the driver defines ->set_attention_status but not
  ->get_attention_status.

There is no driver doing the former and just a single driver doing the
latter, namely pnv_php.c.  Amend it with a ->get_attention_status
callback.  With that, the hotplug_slot_info becomes completely unused by
the PCI hotplug core.  But a few drivers use it internally as a cache:

cpcihp uses it to cache the latch_status and adapter_status.
cpqhp uses it to cache the adapter_status.
pnv_php and rpaphp use it to cache the attention_status.
shpchp uses it to cache all four values.

Amend these drivers to cache the information in their private slot
struct.  shpchp's slot struct already contains members to cache the
power_status and adapter_status, so additional members are only needed
for the other two values.  In the case of cpqphp, the cached value is
only accessed in a single place, so instead of caching it, read the
current value from the hardware.

Caution:  acpiphp, cpci, cpqhp, shpchp, asus-wmi and eeepc-laptop
populate the hotplug_slot_info with initial values on probe.  That code
is herewith removed.  There is a theoretical chance that the code has
side effects without which the driver fails to function, e.g. if the
ACPI method to read the adapter status needs to be executed at least
once on probe.  That seems unlikely to me, still maintainers should
review the changes carefully for this possibility.

Rafael adds: "I'm not aware of any case in which it will break anything,
[...] but if that happens, it may be necessary to add the execution of
the control methods in question directly to the initialization part."

Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Tyrel Datwyler <tyreld@linux.vnet.ibm.com>  # drivers/pci/hotplug/rpa*
Acked-by: Sebastian Ott <sebott@linux.ibm.com>        # drivers/pci/hotplug/s390*
Acked-by: Andy Shevchenko <andy.shevchenko@gmail.com> # drivers/platform/x86
Cc: Len Brown <lenb@kernel.org>
Cc: Scott Murray <scott@spiteful.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Oliver OHalloran <oliveroh@au1.ibm.com>
Cc: Gavin Shan <gwshan@linux.vnet.ibm.com>
Cc: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Cc: Corentin Chary <corentin.chary@gmail.com>
Cc: Darren Hart <dvhart@infradead.org>
2018-09-18 17:52:15 -05:00
Lukas Wunner
81c4b5bf30 PCI: hotplug: Constify hotplug_slot_ops
Hotplug drivers cannot declare their hotplug_slot_ops const, making them
attractive targets for attackers, because upon registration of a hotplug
slot, __pci_hp_initialize() writes to the "owner" and "mod_name" members
in that struct.

Fix by moving these members to struct hotplug_slot and constify every
driver's hotplug_slot_ops except for pciehp.

pciehp constructs its hotplug_slot_ops at runtime based on the PCIe
port's capabilities, hence cannot declare them const.  It can be
converted to __write_rarely once that's mainlined:
http://www.openwall.com/lists/kernel-hardening/2016/11/16/3

Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Tyrel Datwyler <tyreld@linux.vnet.ibm.com>  # drivers/pci/hotplug/rpa*
Acked-by: Andy Shevchenko <andy.shevchenko@gmail.com> # drivers/platform/x86
Cc: Len Brown <lenb@kernel.org>
Cc: Scott Murray <scott@spiteful.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Oliver OHalloran <oliveroh@au1.ibm.com>
Cc: Gavin Shan <gwshan@linux.vnet.ibm.com>
Cc: Sebastian Ott <sebott@linux.vnet.ibm.com>
Cc: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Cc: Corentin Chary <corentin.chary@gmail.com>
Cc: Darren Hart <dvhart@infradead.org>
2018-09-18 17:52:15 -05:00
Lukas Wunner
51bbf9bee3 PCI: hotplug: Demidlayer registration with the core
When a hotplug driver calls pci_hp_register(), all steps necessary for
registration are carried out in one go, including creation of a kobject
and addition to sysfs.  That's a problem for pciehp once it's converted
to enable/disable the slot exclusively from the IRQ thread:  The thread
needs to be spawned after creation of the kobject (because it uses the
kobject's name), but before addition to sysfs (because it will handle
enable/disable requests submitted via sysfs).

pci_hp_deregister() does offer a ->release callback that's invoked
after deletion from sysfs and before destruction of the kobject.  But
because pci_hp_register() doesn't offer a counterpart, hotplug drivers'
->probe and ->remove code becomes asymmetric, which is error prone
as recently discovered use-after-free bugs in pciehp's ->remove hook
have shown.

In a sense, this appears to be a case of the midlayer antipattern:

   "The core thesis of the "midlayer mistake" is that midlayers are
    bad and should not exist.  That common functionality which it is
    so tempting to put in a midlayer should instead be provided as
    library routines which can [be] used, augmented, or ignored by
    each bottom level driver independently.  Thus every subsystem
    that supports multiple implementations (or drivers) should
    provide a very thin top layer which calls directly into the
    bottom layer drivers, and a rich library of support code that
    eases the implementation of those drivers.  This library is
    available to, but not forced upon, those drivers."
        --  Neil Brown (2009), https://lwn.net/Articles/336262/

The presence of midlayer traits in the PCI hotplug core might be ascribed
to its age:  When it was introduced in February 2002, the blessings of a
library approach might not have been well known:
https://git.kernel.org/tglx/history/c/a8a2069f432c

For comparison, the driver core does offer split functions for creating
a kobject (device_initialize()) and addition to sysfs (device_add()) as
an alternative to carrying out everything at once (device_register()).
This was introduced in October 2002:
https://git.kernel.org/tglx/history/c/8b290eb19962

The odd ->release callback in the PCI hotplug core was added in 2003:
https://git.kernel.org/tglx/history/c/69f8d663b595

Clearly, a library approach would not force every hotplug driver to
implement a ->release callback, but rather allow the driver to remove
the sysfs files, release its data structures and finally destroy the
kobject.  Alternatively, a driver may choose to remove everything with
pci_hp_deregister(), then release its data structures.

To this end, offer drivers pci_hp_initialize() and pci_hp_add() as a
split-up version of pci_hp_register().  Likewise, offer pci_hp_del()
and pci_hp_destroy() as a split-up version of pci_hp_deregister().

Eliminate the ->release callback and move its code into each driver's
teardown routine.

Declare pci_hp_deregister() void, in keeping with the usual kernel
pattern that enablement can fail, but disablement cannot.  It only
returned an error if the caller passed in a NULL pointer or a slot which
has never or is no longer registered or is sharing its name with another
slot.  Those would be bugs, so WARN about them.  Few hotplug drivers
actually checked the return value and those that did only printed a
useless error message to dmesg.  Remove that.

For most drivers the conversion was straightforward since it doesn't
matter whether the code in the ->release callback is executed before or
after destruction of the kobject.  But in the case of ibmphp, it was
unclear to me whether setting slot_cur->ctrl and slot_cur->bus_on to
NULL needs to happen before the kobject is destroyed, so I erred on
the side of caution and ensured that the order stays the same.  Another
nontrivial case is pnv_php, I've found the list and kref logic difficult
to understand, however my impression was that it is safe to delete the
list element and drop the references until after the kobject is
destroyed.

Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Andy Shevchenko <andy.shevchenko@gmail.com>  # drivers/platform/x86
Cc: Rafael J. Wysocki <rjw@rjwysocki.net>
Cc: Len Brown <lenb@kernel.org>
Cc: Scott Murray <scott@spiteful.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Gavin Shan <gwshan@linux.vnet.ibm.com>
Cc: Sebastian Ott <sebott@linux.vnet.ibm.com>
Cc: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Cc: Corentin Chary <corentin.chary@gmail.com>
Cc: Darren Hart <dvhart@infradead.org>
Cc: Andy Shevchenko <andy@infradead.org>
2018-07-23 17:04:13 -05:00
Julia Lawall
5d9c6b8ae9 PCI: pnv_php: Add missing of_node_put()
The device node iterators perform an of_node_get() on each iteration, so a
jump out of the loop requires an of_node_put().

The semantic patch that fixes this problem is as follows
(http://coccinelle.lip6.fr):

// <smpl>
@@
expression root,e;
local idexpression child;
iterator name for_each_child_of_node;
@@

 for_each_child_of_node(root, child) {
   ... when != of_node_put(child)
       when != e = child
+  of_node_put(child);
?  break;
   ...
}
... when != child
// </smpl>

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2018-05-23 16:48:37 -05:00
Simon Guo
97c6f25d58 PCI/hotplug: ppc: correct a php_slot usage after free
In pnv_php_unregister_one(), pnv_php_put_slot() might kfree
php_slot structure. But there is pci_hp_deregister() after
that with php_slot reference.

This patch moves pnv_php_put_slot() to the end of function.

Signed-off-by: Simon Guo <wei.guo.simon@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-13 15:50:32 +11:00
Bjorn Helgaas
ab8c609356 Merge branch 'pci/spdx' into next
* pci/spdx:
  PCI: Add SPDX GPL-2.0+ to replace implicit GPL v2 or later statement
  PCI: Add SPDX GPL-2.0+ to replace GPL v2 or later boilerplate
  PCI: Add SPDX GPL-2.0 to replace COPYING boilerplate
  PCI: Add SPDX GPL-2.0 to replace GPL v2 boilerplate
  PCI: Add SPDX GPL-2.0 when no license was specified
2018-02-01 11:40:07 -06:00
Bjorn Helgaas
736759ef59 PCI: Add SPDX GPL-2.0+ to replace GPL v2 or later boilerplate
Add SPDX GPL-2.0+ to all PCI files that specified the GPL and allowed
either GPL version 2 or any later version.

Remove the boilerplate GPL version 2 or later language, relying on the
assertion in b24413180f ("License cleanup: add SPDX GPL-2.0 license
identifier to files with no license") that the SPDX identifier may be used
instead of the full boilerplate text.

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-01-28 15:49:06 -06:00
Frederick Lawler
7506dc7989 PCI: Add wrappers for dev_printk()
Add PCI-specific dev_printk() wrappers and use them to simplify the code
slightly.  No functional change intended.

Signed-off-by: Frederick Lawler <fred@fredlawl.com>
[bhelgaas: squash into one patch]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2018-01-18 12:55:24 -06:00
Markus Elfring
c7abb2352c PCI: Remove unnecessary messages for memory allocation failures
Per ebfdc40969 ("checkpatch: attempt to find unnecessary 'out of memory'
messages"), when a memory allocation fails, the memory subsystem emits
generic "out of memory" messages (see slab_out_of_memory() for some of this
logging).  Therefore, additional error messages in the caller don't add
much value.

Remove messages that merely report "out of memory".

This preserves some messages that report additional information, e.g.,
allocation failures that mean we drop hotplug events.

This issue was detected by using the Coccinelle software.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
[bhelgaas: changelog, squash patches, make similar changes to acpiphp,
cpqphp, ibmphp, keep warning when dropping hotplug event]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2018-01-17 08:41:41 -06:00
Rob Herring
b63773a801 PCI: Convert to using %pOF instead of full_name()
Now that we have a custom printf format specifier, convert users of
full_name() to use %pOF instead.  This is preparation for removing storing
of the full path string for each node.

Signed-off-by: Rob Herring <robh@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Tyrel Datwyler <tyreld@linux.vnet.ibm.com>
Cc: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: Jonathan Hunter <jonathanh@nvidia.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
2017-08-24 11:24:59 -05:00
Linus Torvalds
b286cedd47 powerpc updates for 4.11 part 2
Highlights include:
 
  - An update of the disassembly code used by xmon to the latest versions in
    binutils. We've received permission from all the authors of the relevant
    binutils changes to relicense their changes to the relevant files from GPLv3
    to GPLv2, for inclusion in Linux. Thanks to Peter Bergner for doing the leg
    work to get permission from everyone.
 
  - Addition of the "architected" Power9 CPU table entry, allowing us to boot
    in Power9 architected mode under a hypervisor.
 
  - Updates to the Power9 PMU code.
 
  - Implementation of clear_bit_unlock_is_negative_byte() to optimise
    unlock_page().
 
  - Freescale updates from Scott: "Highlights include 8xx breakpoints and perf,
    t1042rdb display support, and board updates."
 
 Thanks to:
   Al Viro, Andrew Donnellan, Aneesh Kumar K.V, Balbir Singh, Douglas Miller,
   Frédéric Weisbecker, Gavin Shan, Madhavan Srinivasan, Michael Roth, Nathan
   Fontenot, Naveen N. Rao, Nicholas Piggin, Peter Bergner, Paul E. McKenney,
   Rashmica Gupta, Russell Currey, Sahil Mehta, Stewart Smith.
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Merge tag 'powerpc-4.11-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull more powerpc updates from Michael Ellerman:
 "Highlights include:

   - an update of the disassembly code used by xmon to the latest
     versions in binutils. We've received permission from all the
     authors of the relevant binutils changes to relicense their changes
     to the relevant files from GPLv3 to GPLv2, for inclusion in Linux.
     Thanks to Peter Bergner for doing the leg work to get permission
     from everyone.

   - addition of the "architected" Power9 CPU table entry, allowing us
     to boot in Power9 architected mode under a hypervisor.

   - updates to the Power9 PMU code.

   - implementation of clear_bit_unlock_is_negative_byte() to optimise
     unlock_page().

   - Freescale updates from Scott: "Highlights include 8xx breakpoints
     and perf, t1042rdb display support, and board updates."

  Thanks to:
    Al Viro, Andrew Donnellan, Aneesh Kumar K.V, Balbir Singh, Douglas
    Miller, Frédéric Weisbecker, Gavin Shan, Madhavan Srinivasan,
    Michael Roth, Nathan Fontenot, Naveen N. Rao, Nicholas Piggin, Peter
    Bergner, Paul E. McKenney, Rashmica Gupta, Russell Currey, Sahil
    Mehta, Stewart Smith"

* tag 'powerpc-4.11-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (48 commits)
  powerpc: Remove leftover cputime_to_nsecs call causing build error
  powerpc/mm/hash: Always clear UPRT and Host Radix bits when setting up CPU
  powerpc/optprobes: Fix TOC handling in optprobes trampoline
  powerpc/pseries: Advertise Hot Plug Event support to firmware
  cxl: fix nested locking hang during EEH hotplug
  powerpc/xmon: Dump memory in CPU endian format
  powerpc/pseries: Revert 'Auto-online hotplugged memory'
  powerpc/powernv: Make PCI non-optional
  powerpc/64: Implement clear_bit_unlock_is_negative_byte()
  powerpc/powernv: Remove unused variable in pnv_pci_sriov_disable()
  powerpc/kernel: Remove error message in pcibios_setup_phb_resources()
  powerpc/mm: Fix typo in set_pte_at()
  pci/hotplug/pnv-php: Disable MSI and PCI device properly
  pci/hotplug/pnv-php: Disable surprise hotplug capability on conflicts
  pci/hotplug/pnv-php: Remove WARN_ON() in pnv_php_put_slot()
  powerpc: Add POWER9 architected mode to cputable
  powerpc/perf: use is_kernel_addr macro in perf_get_misc_flags()
  powerpc/perf: Avoid FAB_*_MATCH checks for power9
  powerpc/perf: Add restrictions to PMC5 in power9 DD1
  powerpc/perf: Use Instruction Counter value
  ...
2017-03-01 10:10:16 -08:00
Gavin Shan
49f4b08e61 pci/hotplug/pnv-php: Disable MSI and PCI device properly
pnv_php_disable_irq() can be called in two paths: Bailing path in
pnv_php_enable_irq() or releasing slot. The MSI (or MSIx) interrupts
is disabled unconditionally in pnv_php_disable_irq(). It's wrong
because that might be enabled by drivers other than pnv-php.

This disables MSI (or MSIx) interrupts and the PCI device only if
it was enabled by pnv-php. In the error path of pnv_php_enable_irq(),
we rely on the newly added parameter @disable_device. In the path
of releasing slot, @pnv_php->irq is checked.

Cc: <stable@vger.kernel.org> # v4.9+
Fixes: 360aebd85a ("drivers/pci/hotplug: Support surprise hotplug in powernv driver")
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-02-17 22:13:29 +11:00
Gavin Shan
303529d6ef pci/hotplug/pnv-php: Disable surprise hotplug capability on conflicts
The root port or PCIe switch downstream port might have been associated
with driver other than pnv-php. The MSI or MSIx might also have been
enabled by that driver (e.g. pcieport_drv). Attempt to enable MSI incurs
below backtrace:

 PowerPC PowerNV PCI Hotplug Driver version: 0.1
 ------------[ cut here ]------------
 WARNING: CPU: 19 PID: 1004 at drivers/pci/msi.c:1071 \
                              __pci_enable_msi_range+0x84/0x4e0
 NIP [c000000000665c34] __pci_enable_msi_range+0x84/0x4e0
 LR [c000000000665c24] __pci_enable_msi_range+0x74/0x4e0
 Call Trace:
 [c000000384d67600] [c000000000665c24] __pci_enable_msi_range+0x74/0x4e0
 [c000000384d676e0] [d00000000aa31b04] pnv_php_register+0x564/0x5a0 [pnv_php]
 [c000000384d677c0] [d00000000aa31658] pnv_php_register+0xb8/0x5a0 [pnv_php]
 [c000000384d678a0] [d00000000aa31658] pnv_php_register+0xb8/0x5a0 [pnv_php]
 [c000000384d67980] [d00000000aa31dfc] pnv_php_init+0x60/0x98 [pnv_php]
 [c000000384d679f0] [c00000000000cfdc] do_one_initcall+0x6c/0x1d0
 [c000000384d67ab0] [c000000000b92354] do_init_module+0x94/0x254
 [c000000384d67b40] [c00000000019719c] load_module+0x258c/0x2c60
 [c000000384d67d30] [c000000000197bb0] SyS_finit_module+0xf0/0x170
 [c000000384d67e30] [c00000000000b184] system_call+0x38/0xe0

This fixes the issue by skipping enabling the surprise hotplug
capability if the MSI or MSIx on the PCI slot's upstream port has
been enabled by other driver.

Cc: <stable@vger.kernel.org> # v4.9+
Fixes: 360aebd85a ("drivers/pci/hotplug: Support surprise hotplug in powernv driver")
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Tested-by: Vaibhav Jain <vaibhav@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-02-17 22:13:28 +11:00
Gavin Shan
36c7c9da40 pci/hotplug/pnv-php: Remove WARN_ON() in pnv_php_put_slot()
The WARN_ON() causes unnecessary backtrace when putting the parent
slot, which is likely to be NULL.

 WARNING: CPU: 2 PID: 1071 at drivers/pci/hotplug/pnv_php.c:85 \
                              pnv_php_release+0xcc/0x150 [pnv_php]
    :
 Call Trace:
 [c0000003bc007c10] [d00000000ad613c4] pnv_php_release+0x144/0x150 [pnv_php]
 [c0000003bc007c40] [c0000000006641d8] pci_hp_deregister+0x238/0x330
 [c0000003bc007cd0] [d00000000ad61440] pnv_php_unregister_one+0x70/0xa0 [pnv_php]
 [c0000003bc007d10] [d00000000ad614c0] pnv_php_unregister+0x50/0x80 [pnv_php]
 [c0000003bc007d40] [d00000000ad61e84] pnv_php_exit+0x50/0xcb4 [pnv_php]
 [c0000003bc007d70] [c00000000019499c] SyS_delete_module+0x1fc/0x2a0
 [c0000003bc007e30] [c00000000000b184] system_call+0x38/0xe0

Cc: <stable@vger.kernel.org> # v4.8+
Fixes: 66725152fb ("PCI/hotplug: PowerPC PowerNV PCI hotplug driver")
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Tested-by: Vaibhav Jain <vaibhav@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-02-17 22:13:27 +11:00
Gavin Shan
454593e54c drivers/pci/hotplug: Mask PDC interrupt if required
We're supporting surprise hotplug on PCI slots behind root port
or PCIe switch downstream ports, which don't claim the capability
in hardware register (offset: PCIe cap + PCI_EXP_SLTCAP). PEX8718
is one of the examples. For those PCI slots, the PDC (Presence
Detection Change) event isn't reliable and the underly (skiboot)
firmware has best judgement.

This masks the PDC event when skiboot requests by "ibm,slot-broken-pdc"
property in PCI slot's device-tree node.

Reported-by: Hank Chang <hankmax0000@gmail.com>
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Tested-by: Willie Liauw <williel@supermicro.com.tw>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-02-15 20:02:43 +11:00
Gavin Shan
d0c424971f drivers/pci/hotplug: Fix initial state for empty slot
In PowerNV PCI hotplug driver, the initial PCI slot's state is set
to PNV_PHP_STATE_POPULATED if no PCI devices are connected to the
slot. The PCI devices that are hot added to the slot won't be probed
and populated because of the check in pnv_php_enable():

        /* Check if the slot has been configured */
        if (php_slot->state != PNV_PHP_STATE_REGISTERED)
                return 0;

This fixes the issue by leaving the slot in PNV_PHP_STATE_REGISTERED
state initially if nothing is connected to the slot.

Fixes: 360aebd85a ("drivers/pci/hotplug: Support surprise hotplug in powernv driver")
Cc: stable@vger.kernel.org #v4.9+
Reported-by: Hank Chang <hankmax0000@gmail.com>
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Tested-by: Willie Liauw <williel@supermicro.com.tw>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-02-15 20:02:43 +11:00
Gavin Shan
d7d55536c6 drivers/pci/hotplug: Handle presence detection change properly
The surprise hotplug is driven by interrupt in PowerNV PCI hotplug
driver. In the interrupt handler, pnv_php_interrupt(), we bail when
pnv_pci_get_presence_state() returns zero wrongly. It causes the
presence change event is always ignored incorrectly.

This fixes the issue by bailing on error (non-zero value) returned
from pnv_pci_get_presence_state().

Fixes: 360aebd85a ("drivers/pci/hotplug: Support surprise hotplug in powernv driver")
Cc: stable@vger.kernel.org #v4.9+
Reported-by: Hank Chang <hankmax0000@gmail.com>
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Tested-by: Willie Liauw <williel@supermicro.com.tw>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-02-15 20:02:43 +11:00
Peter Zijlstra
2c935bc572 locking/atomic, kref: Add kref_read()
Since we need to change the implementation, stop exposing internals.

Provide kref_read() to read the current reference count; typically
used for debug messages.

Kills two anti-patterns:

	atomic_read(&kref->refcount)
	kref->refcount.counter

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-01-14 11:37:18 +01:00
Gavin Shan
39f0d6fbdc drivers/pci/hotplug: Use of_property_read_u32() in powernv driver
This replaces of_get_property() with of_property_read_u32() or
of_property_read_string() so that we needn't consider the endian
issue, the returned value always is in CPU-endian.

Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
[mpe: Fold in the change to the "ibm,slot-surprise-pluggable" case]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-10-04 16:22:47 +11:00
Gavin Shan
360aebd85a drivers/pci/hotplug: Support surprise hotplug in powernv driver
This supports PCI surprise hotplug. The design is highlighted as
below:

   * The PCI slot's surprise hotplug capability is exposed through
     device node property "ibm,slot-surprise-pluggable", meaning
     PCI surprise hotplug will be disabled if skiboot doesn't support
     it yet.
   * The interrupt because of presence or link state change is raised
     on surprise hotplug event. One event is allocated and queued to
     the PCI slot for workqueue to pick it up and process in serialized
     fashion. The code flow for surprise hotplug is same to that for
     managed hotplug except: the affected PEs are put into frozen state
     to avoid unexpected EEH error reporting in surprise hot remove path.

Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-09-29 15:02:28 +10:00
Gavin Shan
149ba66a90 drivers/pci/hotplug: Remove likely() and unlikely() in powernv driver
This removes likely() and unlikely() in pnv_php.c as the code isn't
running in hot path. Those macros to affect CPU's branch stream don't
help a lot for performance. I used them to identify the cases are
likely or unlikely to happen. No logical changes introduced.

Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-09-29 15:01:55 +10:00
Andrew Donnellan
5473a6bf63 PCI/hotplug: pnv_php: handle OPAL_PCI_SLOT_OFFLINE power state
When calling pnv_php_set_slot_power_state() with state ==
OPAL_PCI_SLOT_OFFLINE, remove devices from the device tree as if we're
dealing with OPAL_PCI_SLOT_POWER_OFF.

Cc: Gavin Shan <gwshan@linux.vnet.ibm.com>
Cc: linux-pci@vger.kernel.org
Cc: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: Ian Munsie <imunsie@au1.ibm.com>
Acked-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-07-14 20:28:10 +10:00
Andrew Donnellan
89379f165a PCI/hotplug: pnv_php: export symbols and move struct types needed by cxl
The cxl driver will use infrastructure from pnv_php to handle device tree
updates when switching bi-modal CAPI cards into CAPI mode.

To enable this, export pnv_php_find_slot() and
pnv_php_set_slot_power_state(), and add corresponding declarations, as well
as the definition of struct pnv_php_slot, to asm/pnv-pci.h.

Cc: Gavin Shan <gwshan@linux.vnet.ibm.com>
Cc: linux-pci@vger.kernel.org
Cc: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: Ian Munsie <imunsie@au1.ibm.com>
Acked-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-07-14 20:28:08 +10:00
Gavin Shan
66725152fb PCI/hotplug: PowerPC PowerNV PCI hotplug driver
This adds standalone driver to support PCI hotplug for PowerPC PowerNV
platform that runs on top of skiboot firmware. The firmware identifies
hotpluggable slots and marked their device tree node with proper
"ibm,slot-pluggable" and "ibm,reset-by-firmware". The driver scans
device tree nodes to create/register PCI hotplug slot accordingly.

The PCI slots are organized in fashion of tree, which means one
PCI slot might have parent PCI slot and parent PCI slot possibly
contains multiple child PCI slots. At the plugging time, the parent
PCI slot is populated before its children. The child PCI slots are
removed before their parent PCI slot can be removed from the system.

If the skiboot firmware doesn't support slot status retrieval, the PCI
slot device node shouldn't have property "ibm,reset-by-firmware". In
that case, none of valid PCI slots will be detected from device tree.
The skiboot firmware doesn't export the capability to access attention
LEDs yet and it's something for TBD.

Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-06-21 15:30:58 +10:00