Tear down and free the four-level page tables of physical mappings
during memory hotremove.

Borrow the basic structure of remove_pagetable() and friends from the
identically-named x86 functions. Reduce the frequency of tlb flushes and
page_table_lock spinlocks by only doing them in the outermost function.
There was some question as to whether the locking is needed at all.
Leave it for now, but we could consider dropping it.

Memory must be offline to be removed, thus not in use. So there
shouldn't be the sort of concurrent page walking activity here that
might prompt us to use RCU.
Signed-off-by: Reza Arbab <arbab@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Wire up memory hotplug page mapping for radix. Share the mapping
function already used by radix_init_pgtable().
Signed-off-by: Reza Arbab <arbab@linux.vnet.ibm.com>
Acked-by: Balbir Singh <bsingharora@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Move the page mapping code in radix_init_pgtable() into a separate
function that will also be used for memory hotplug.

The current goto loop progressively decreases its mapping size as it
covers the tail of a range whose end is unaligned. Change this to a for
loop which can do the same for both ends of the range.
Signed-off-by: Reza Arbab <arbab@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Use the new non-PCI ISA bridge support to expose the POWER9
LPC bus as direct mapped via the ISA IO port range. This
enables direct access via drivers such as 8250
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

The POWER9 chip supports an LPC bus that isn't hanging
off a PCI bus, so let's add support for that, mapping it
to the reserved space at ISA_IO_BASE
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

We'll be adding non-PCI isa bridge support so let's not
have all the definition in pci-bridge.h
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Document the device-tree bindings defining the the properties under
the @power-mgt node in the device tree that describe the idle states
for Linux running on baremetal POWER servers.

These bindings are documented separately instead of using the the
common idle state bindings since the idle-states on POWER servers
are exposed as property arrays where as the common idle state bindings
expect idle-states to be described as nodes.
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

The power9_idle_stop method currently takes only the requested stop
level as a parameter and picks up the rest of the PSSCR bits from a
hand-coded macro. This is not a very flexible design, especially when
the firmware has the capability to communicate the psscr value and the
mask associated with a particular stop state via device tree.

This patch modifies the power9_idle_stop API to take as parameters the
PSSCR value and the PSSCR mask corresponding to the stop state that
needs to be set. These PSSCR value and mask are respectively obtained
by parsing the "ibm,cpu-idle-state-psscr" and
"ibm,cpu-idle-state-psscr-mask" fields from the device tree.

In addition to this, the patch adds support for handling stop states
for which ESL and EC bits in the PSSCR are zero. As per the
architecture, a wakeup from these stop states resumes execution from
the subsequent instruction as opposed to waking up at the System
Vector.

The older firmware sets only the Requested Level (RL) field in the
psscr and psscr-mask exposed in the device tree. For older firmware
where psscr-mask=0xf, this patch will set the default sane values that
the set for for remaining PSSCR fields (i.e PSLL, MTL, ESL, EC, and
TR). For the new firmware, the patch will validate that the invariants
required by the ISA for the psscr values are maintained by the
firmware.

This skiboot patch that exports fully populated PSSCR values and the
mask for all the stop states can be found here:
https://lists.ozlabs.org/pipermail/skiboot/2016-September/004869.html

[Optimize the number of instructions before entering STOP with
ESL=EC=0, validate the PSSCR values provided by the firimware
maintains the invariants required as per the ISA suggested by Balbir
Singh]
Acked-by: Balbir Singh <bsingharora@gmail.com>
Signed-off-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

In the current code for powernv_add_idle_states, there is a lot of code
duplication while initializing an idle state in powernv_states table.

Add an inline helper function to populate the powernv_states[] table
for a given idle state. Invoke this for populating the "Nap",
"Fastsleep" and the stop states in powernv_add_idle_states.
Signed-off-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com>
Acked-by: Balbir Singh <bsingharora@gmail.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Balbir pointed out that the name of the function pnv_arch300_idle_init
was inconsistent with the names of the variables and functions
pertaining to POWER9 features in book3s_idle.S.

This patch renames pnv_arch300_idle_init to pnv_power9_idle_init.

This patch does not change any behaviour.
Signed-off-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Currently all the low-power idle states are expected to wake up
at reset vector 0x100. Which is why the macro IDLE_STATE_ENTER_SEQ
that puts the CPU to an idle state and never returns.

On ISA v3.0, when the ESL and EC bits in the PSSCR are zero, the CPU
is expected to wake up at the next instruction of the idle
instruction.

This patch adds a new macro named IDLE_STATE_ENTER_SEQ_NORET for the
no-return variant and reuses the name IDLE_STATE_ENTER_SEQ
for a variant that allows resuming operation at the instruction next
to the idle-instruction.
Acked-by: Balbir Singh <bsingharora@gmail.com>
Signed-off-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Add detection of NPU2 PHBs. NPU2/NVLink2 has a different register
layout for the TCE kill register therefore TCE invalidation should be
done via the OPAL call rather than using the register directly as it
is for PHB3 and NVLink1. This changes TCE invalidation to use the OPAL
call in the case of a NPU2 PHB model.
Signed-off-by: Alistair Popple <alistair@popple.id.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

POWER9 contains an off core mmu called the nest mmu (NMMU). This is
used by other hardware units on the chip to translate virtual
addresses into real addresses. The unit attempting an address
translation provides the majority of the context required for the
translation request except for the base address of the partition table
(ie. the PTCR) which needs to be programmed into the NMMU.

This patch adds a call to OPAL to set the PTCR for the nest mmu in
opal_init().
Signed-off-by: Alistair Popple <alistair@popple.id.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Relax the check preventing us from hotplugging into an offline node.

This limitation was added in commit 482ec7c4 ("[PATCH] powerpc numa:
Support sparse online node map") to prevent adding resources to an
uninitialized node.

These days, there is no harm in doing so. The addition will actually
cause the node to be initialized and onlined; add_memory_resource()
calls hotadd_new_pgdat() (if necessary) and node_set_online().
Signed-off-by: Reza Arbab <arbab@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

The flow of the main loop in parse_numa_properties() is overly
complicated. Simplify it to be less confusing and easier to read.
No functional change.

The end of the main loop in parse_numa_properties() looks like this:

	for_each_node_by_type(...) {
		...
		if (!condition) {
			if (--ranges)
				goto new_range;
			else
				continue;
		}

		statement();

		if (--ranges)
			goto new_range;
		/* else
		 *	continue; <- implicit, this is the end of the loop
		 */
	}

The only effect of !condition is to skip execution of statement(). This
can be rewritten in a simpler way:

	for_each_node_by_type(...) {
		...
		if (condition)
			statement();

		if (--ranges)
			goto new_range;
	}
Signed-off-by: Reza Arbab <arbab@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

There are chances that multiple CPUs can call crash_fadump() simultaneously
and would start duplicating same info to vmcoreinfo ELF note section. This
causes makedumpfile to fail during kdump capture. One example is,
triggering dumprestart from HMC which sends system reset to all the CPUs at
once.

makedumpfile --dump-dmesg /proc/vmcore
read_vmcoreinfo_basic_info: Invalid data in /tmp/vmcoreinfoyjgxlL: CRASHTIME=1475605971CRASHTIME=1475605971CRASHTIME=1475605971CRASHTIME=1475605971CRASHTIME=1475605971CRASHTIME=1475605971CRASHTIME=1475605971CRASHTIME=1475605971
makedumpfile Failed.
Running makedumpfile --dump-dmesg /proc/vmcore failed (1).

makedumpfile  -d 31 -l /proc/vmcore
read_vmcoreinfo_basic_info: Invalid data in /tmp/vmcoreinfo1mmVdO: CRASHTIME=1475605971CRASHTIME=1475605971CRASHTIME=1475605971CRASHTIME=1475605971CRASHTIME=1475605971CRASHTIME=1475605971CRASHTIME=1475605971CRASHTIME=1475605971
makedumpfile Failed.
Running makedumpfile  -d 31 -l /proc/vmcore failed (1).
Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

The proto VSID is built using both the MMU context id and effective
segment ID (ESID). We should not have overlapping bits between those.
That could result in us having a VSID collision. With the current code
we missed masking the top bits of the ESID. This implies for kernel
address we ended up using the top 4 bits of the ESID as part of the
proto VSID, which is wrong.

The current code use the top 4 context values (0x7fffc - 0x7ffff) for
the kernel. With those context IDs used for the kernel, we don't run
into VSID collisions because we get the same proto VSID irrespective of
whether we mask the ESID bits or not. eg:

  ea         = 0xf000000000000000
  context    = 0x7ffff

  w/out masking:
  proto_vsid = (0x7ffff << 6 | 0xf000000000000000 >> 40)
	     = (0x1ffffc0 | 0xf00000)
	     =  0x1ffffc0

  with masking:
  proto_vsid = (0x7ffff << 6 | ((0xf000000000000000 >> 40) & 0x3f))
	     = (0x1ffffc0 | (0xf00000 & 0x3f))
	     =  0x1ffffc0 | 0)
	     =  0x1ffffc0

So although there is no bug, the code is still overly subtle, so fix it
to save ourselves pain in future.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

With bpf_jit_binary_alloc(), we allocate at a page granularity and fill
the rest of the space with illegal instructions to mitigate BPF spraying
attacks, while having the actual JIT'ed BPF program at a random location
within the allocated space. Under this scenario, it would be better to
flush the entire allocated buffer rather than just the part containing
the actual program. We already flush the buffer from start to the end of
the BPF program. Extend this to include the illegal instructions after
the BPF program.
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

We have a check earlier to ensure we don't proceed if image is NULL. As
such, the redundant check can be removed.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
[Added similar changes for classic BPF JIT]
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

During EEH recovery, we deconfigure all AFUs whilst leaving the
corresponding vPHB and virtual PCI device in place.

If something attempts to interact with the AFU's PCI config space (e.g.
running lspci) after the AFU has been deconfigured and before it's
reconfigured, cxl_pcie_{read,write}_config() will read invalid values from
the deconfigured struct cxl_afu and proceed to Oops when they try to
dereference pointers that have been set to NULL during deconfiguration.

Add a rwsem to struct cxl_afu so we can prevent interaction with config
space while the AFU is deconfigured.
Reported-by: Pradipta Ghosh <pradghos@in.ibm.com>
Suggested-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
Cc: stable@vger.kernel.org # v4.9+
Signed-off-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: Vaibhav Jain <vaibhav@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

This change adds a force psl data cache flush during device shutdown
callback. This should reduce a possibility of psl holding a dirty
cache line while the CAPP is being reinitialized, which may result in
a UE [load/store] machine check error.
Signed-off-by: Vaibhav Jain <vaibhav@linux.vnet.ibm.com>
Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Acked-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

The kernel API does not use anything from this header file.
Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Acked-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

This function already has multiple exit points, so there's no harm
adding another. Although it looks odd to return directly in a function
which takes a lock, we've actually just dropped the mmap_sem in this
code, so there's really no reason to go via a label. And it means we can
drop the unhelpfully named out2 label.
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
[mpe: Rewrite change log]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Setting err and going to ldst_done just returns 0, without using err, so
just return 0 directly. We already do that for other call sites in this
function.
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
[mpe: Rewrite change log]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

The RTAS device-tree node's refcount has been increased by one in
the function call of_find_node_by_name(), but it's missed to be
decreased by one in the error path. It leads to unbalanced refcount
on RTAS device-tree node.

This fixes above issue by decreasing RTAS device-tree node's refcount
in error path.
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

This uses of_property_read_u32() in rtas_initialize() so that we
needn't explicitly care the CPU's endian.
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

This removes the unnecessary nested if statements in function
rtas_initialize(), to simplify the code. No functional changes
introduced.
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Use kmalloc_array(), which checks for overflow of the multiplication,
rather than doing it by hand.
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

In commit a4b34954 ("powerpc/mm: Cleanup LPCR defines") we updated
LPCR_VRMASD wrongly as below.

-#define   LPCR_VRMASD  (0x1ful << (63-16))
+#define   LPCR_VRMASD_SH       47
+#define   LPCR_VRMASD          (ASM_CONST(1) << LPCR_VRMASD_SH)

We initialize the VRMA bits in LPCR to 0x00 in kvm. Hence using a
different mask value as above while updating lpcr should not have any
impact.

This patch updates it to the correct value.

Fixes: a4b34954 ("powerpc/mm: Cleanup LPCR defines")
Reported-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Jia He <hejianet@gmail.com>
Acked-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Currently we have optimized hand-coded assembly checksum routines for
big-endian 64-bit systems, but for little-endian we use the generic C
routines. This modifies the optimized routines to work for
little-endian. With this, we no longer need to enable
CONFIG_GENERIC_CSUM. This also fixes a couple of comments in
checksum_64.S so they accurately reflect what the associated instruction
does.
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
[mpe: Use the more common __BIG_ENDIAN__]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

These functions compute an IP checksum by computing a 64-bit sum and
folding it to 32 bits (the "nofold" in their names refers to folding
down to 16 bits).  However, doing (u32) (s + (s >> 32)) is not
sufficient to fold a 64-bit sum to 32 bits correctly.  The addition
can produce a carry out from bit 31, which needs to be added in to
the sum to produce the correct result.

To fix this, we copy the from64to32() function from lib/checksum.c
and use that.
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

The OPAL memory console is reported to be size zero, as we do not
initialise the struct attr with any size information due to the size
being variable. This leads users to think that the console is empty.

Instead report the maximum size.
Signed-off-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

We now support THP with both 64k and 4K page size configuration
for radix. (hash only support THP with 64K page size). Hence we
will have CONFIG_TRANSPARENT_HUGEPAGE enabled for both PPC_64K
and PPC_4K config. Since we only need large pmd page table
with hash configuration (to store the slot information
in the second half of the table) restrict the large pmd page table
to THP and 64K configs.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Reviewed-by: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

We don't do this for other page table entries. So lets keep this simple
and always return false for hugepd check on a 64K page size config.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Pull x86 fix from Thomas Gleixner:
 "Restore the retrigger callbacks in the IO APIC irq chips. That
  addresses a long standing regression which got introduced with the
  rewrite of the x86 irq subsystem two years ago and went unnoticed so
  far"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/ioapic: Restore IO-APIC irq_chip retrigger callback

Pull smp/hotplug fix from Thomas Gleixner:
 "Remove an unused variable which is a leftover from the notifier
  removal"

* 'smp-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  cpu/hotplug: Remove unused but set variable in _cpu_down()

Pull virtio/vhost fixes from Michael Tsirkin:
 "Random fixes and cleanups that accumulated over the time"

* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
  virtio/s390: virtio: constify virtio_config_ops structures
  virtio/s390: add missing \n to end of dev_err message
  virtio/s390: support READ_STATUS command for virtio-ccw
  tools/virtio/ringtest: tweaks for s390
  tools/virtio/ringtest: fix run-on-all.sh for offline cpus
  virtio_console: fix a crash in config_work_handler
  vhost/scsi: silence uninitialized variable warning
  vhost: scsi: constify target_core_fabric_ops structures

Pull thermal management fixes from Zhang Rui:

 - fix a regression that thermal zone dynamically allocated sysfs
   attributes are freed before they're removed, which is introduced in
   4.10-rc1 (Jacob von Chorus)

 - fix a boot warning because deprecated hwmon API is used (Fabio
   Estevam)

 - a couple of fixes for rockchip thermal driver (Brian Norris, Caesar
   Wang)

* 'for-rc' of git://git.kernel.org/pub/scm/linux/kernel/git/rzhang/linux:
  thermal: rockchip: fixes the conversion table
  thermal: core: move tz->device.groups cleanup to thermal_release
  thermal: thermal_hwmon: Convert to hwmon_device_register_with_info()
  thermal: rockchip: handle set_trips without the trip points
  thermal: rockchip: optimize the conversion table
  thermal: rockchip: fixes invalid temperature case
  thermal: rockchip: don't pass table structs by value
  thermal: rockchip: improve conversion error messages

Pull USB fixes from Greg KH:
 "Here are a few small USB fixes for 4.10-rc5.

  Most of these are gadget/dwc2 fixes for reported issues, all of these
  have been in linux-next for a while. The last one is a single xhci
  WARN_ON removal to handle an issue that the dwc3 driver is hitting in
  the 4.10-rc tree. The warning is harmless and needs to be removed, and
  a "real" fix that is more complex will show up in 4.11-rc1 for this
  device.

  That last patch hasn't been in linux-next yet due to the weekend
  timing, but it's a "simple" WARN_ON() removal so what could go wrong?
  :)"

Famous last words.

* tag 'usb-4.10-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb:
  xhci: remove WARN_ON if dma mask is not set for platform devices
  usb: dwc2: host: fix Wmaybe-uninitialized warning
  usb: dwc2: gadget: Fix GUSBCFG.USBTRDTIM value
  usb: gadget: udc: atmel: remove memory leak
  usb: dwc3: exynos fix axius clock error path to do cleanup
  usb: dwc2: Avoid suspending if we're in gadget mode
  usb: dwc2: use u32 for DT binding parameters
  usb: gadget: f_fs: Fix iterations on endpoints.
  usb: dwc2: gadget: Fix DMA memory freeing
  usb: gadget: composite: Fix function used to free memory