Block allocation requires a permanent transaction for deferred AGFL
frees. Add an assert in the block allocation path to make explicit and
obvious to future callers the requirement of a transaction with a
permanent reservation.
Reported-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
[darrick: split this out from the previous patch per hch request]
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
In preparation to enabling -Wimplicit-fallthrough, mark switch
cases where we are expecting to fall through.
This patch fixes the following warnings:
drivers/memstick/host/jmb38x_ms.c: In function ‘jmb38x_ms_write_data’:
drivers/memstick/host/jmb38x_ms.c:261:15: warning: this statement may fall through [-Wimplicit-fallthrough=]
host->io_pos++;
~~~~~~~~~~~~^~
drivers/memstick/host/jmb38x_ms.c:262:2: note: here
case 2:
^~~~
drivers/memstick/host/jmb38x_ms.c:264:15: warning: this statement may fall through [-Wimplicit-fallthrough=]
host->io_pos++;
~~~~~~~~~~~~^~
drivers/memstick/host/jmb38x_ms.c:265:2: note: here
case 1:
^~~~
drivers/memstick/host/tifm_ms.c: In function ‘tifm_ms_write_data’:
drivers/memstick/host/tifm_ms.c:168:15: warning: this statement may fall through [-Wimplicit-fallthrough=]
host->io_pos++;
~~~~~~~~~~~~^~
drivers/memstick/host/tifm_ms.c:169:2: note: here
case 2:
^~~~
drivers/memstick/host/tifm_ms.c:171:15: warning: this statement may fall through [-Wimplicit-fallthrough=]
host->io_pos++;
~~~~~~~~~~~~^~
drivers/memstick/host/tifm_ms.c:172:2: note: here
case 1:
^~~~
Warning level 3 was used: -Wimplicit-fallthrough=3
This patch is part of the ongoing efforts to enable
-Wimplicit-fallthrough.
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
In preparation to enabling -Wimplicit-fallthrough, mark switch
cases where we are expecting to fall through.
This patch fixes the following warning:
drivers/net/xen-netfront.c: In function ‘netback_changed’:
drivers/net/xen-netfront.c:2038:6: warning: this statement may fall through [-Wimplicit-fallthrough=]
if (dev->state == XenbusStateClosed)
^
drivers/net/xen-netfront.c:2041:2: note: here
case XenbusStateClosing:
^~~~
Warning level 3 was used: -Wimplicit-fallthrough=3
Notice that, in this particular case, the code comment is modified
in accordance with what GCC is expecting to find.
This patch is part of the ongoing efforts to enable
-Wimplicit-fallthrough.
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Add a new command-line option "xen_timer_slop=<INT>" that sets the
minimum delta of virtual Xen timers. This commit does not change the
default timer slop value for virtual Xen timers.
Lowering the timer slop value should improve the accuracy of virtual
timers (e.g., better process dispatch latency), but it will likely
increase the number of virtual timer interrupts (relative to the
original slop setting).
The original timer slop value has not changed since the introduction
of the Xen-aware Linux kernel code. This commit provides users an
opportunity to tune timer performance given the refinements to
hardware and the Xen event channel processing. It also mirrors
a feature in the Xen hypervisor - the "timer_slop" Xen command line
option.
[boris: updated comment describing TIMER_SLOP]
Signed-off-by: Ryan Thibodeaux <ryan.thibodeaux@starlab.io>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Add support for the CPU-Measurement Facility counter
second version number 6. This number is used to detect some
more counters in the crypto counter set and the extended
counter set.
Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Reviewed-by: Hendrik Brueckner <brueckner@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Define the gup_fast_permitted to check against the asce_limit of the
mm attached to the current task, then replace the s390 specific gup
code with the generic implementation in mm/gup.c.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Change the way how pgd_offset, p4d_offset, pud_offset and pmd_offset
walk the page tables. pgd_offset now always calculates the index for
the top-level page table and adds it to the pgd, this is either a
segment table offset for a 2-level setup, a region-3 offset for 3-levels,
region-2 offset for 4-levels, or a region-1 offset for a 5-level setup.
The other three functions p4d_offset, pud_offset and pmd_offset will
only add the respective offset if they dereference the passed pointer.
With the new way of walking the page tables a sequence like this from
mm/gup.c now works:
pgdp = pgd_offset(current->mm, addr);
pgd = READ_ONCE(*pgdp);
p4dp = p4d_offset(&pgd, addr);
p4d = READ_ONCE(*p4dp);
pudp = pud_offset(&p4d, addr);
pud = READ_ONCE(*pudp);
pmdp = pmd_offset(&pud, addr);
pmd = READ_ONCE(*pmdp);
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Since commit 09bb839434 we don't use the state argument for any sort
of on-stack caching in the io read and write path. Remove the stale
and unused argument from them, and bubble it up to __io_submit_sqe()
and down to io_prep_rw().
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The AHB queue manager and Network Processing Engines are
present on all IXP4xx SoCs, so we add them to the overarching
device tree include.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
This makes the queue manager driver able to probe from the device
tree. It only needs to get a memory resource and two interrupts
and the platform device provides these as resources, so all is
pretty simple.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
This adds device tree bindings for the Intel IXP4xx AHB
Queue Manager.
Cc: devicetree@vger.kernel.org
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
This makes the NPE driver able to probe from the device tree.
It only needs to get three memory resources and the plaform
device provide these, so all is pretty simple.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
This adds DT bindings for the Intel IXP4xx Network Processing
Engine (NPE). These are three firmware-executing units found in
the IXP4xx SoC. These bindings use YAML.
Cc: devicetree@vger.kernel.org
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Instead of using hardcoded base address implicitly
obtained through <linux/io.h>, pass the physical base
for the QMGR block as a memory resource and remap
it in the driver.
Also pass the two IRQs as resources and obtain them
in the driver.
Use devm_* accessors and simplify the error path in the
process. Drop memory region request as this is done by
the devm_ioremap* functions.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
These former inlines turn out to be unused in the kernel.
If they are needed in the future, they can be resurrected
by reverting or studying this commit.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
These inline functions immediately exploit the static ioremaps
for the queue manager memory region. This does not work with
multiplatform where everything need to be dynamically remapped,
so get rid of these inlines and create new exports for those
used by other drivers.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Instead of using hardcoded base addresses implicitly
obtained through <linux/io.h>, pass the physical base
for the three NPE blocks as memory resources and remap
these in the driver.
Drop the memory request region business, this will
anyways be done by devm_* remapping functions.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Instead of registering everything related to the QMGR
unconditionally in the module_init() call (which will
never work with multiplatform) create a platform device
and probe the QMGR like any other device.
Put the device second in the list of devices added for
the platform so it is there when the dependent network
and crypto drivers probe later on.
This probe() path will not be taken unconditionally on
device tree boots, so remove the DT guard.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Instead of registering everything related to the NPE
unconditionally in the module_init() call (which will
never work with multiplatform) create a platform device
and probe the NPE like any other device.
Put the device first in the list of devices added for
the platform so it is there when the dependent network
and crypto drivers probe later on.
This probe() path will not be taken unconditionally on
device tree boots, so remove the DT guard.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
This moves the IXP4xx Queue Manager and Network Processing
Engine headers out of the <mack/*> include path as that is
incompatible with multiplatform.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
The Network Processing Engine and Queue Manager are
versatile firmware components used by several IXP4xx
drivers.
Drivers are relying on getting access to these components
using <mach/*> headers which does not work with
multiplatform. We need to find a better place for the
drivers to live.
Let's first move them to drivers/soc and the start to
refactor a bit by passing resources and moving headers.
This patch introduce static IRQ assignments but that
will be fixed by later patches in this series.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
This adds a device tree for the IXP4xx-based Linksys
NSLU2 and Gateworks GW2358 which encompass the Gateworks
Cambria family.
These will be the first IXP4xx device tree platforms.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
This adds a minimal support for booting IXP4xx systems
from device tree.
We have to add hacks to the QMGR, NPE and notably also
ethernet and watchdog drivers so that they don't crash
the platform: these drivers are unconditionally starting
to grab regions of statically remapped IO space with no
concern of the device model or other platforms.
We will go in and properly fix these drivers as we go
along but for now this hack gets us to a place where we
can start working on proper device tree support for these
platforms.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
This adds initial device tree bindings for the IXP4xx machines.
This time I tried something wild and crazy and try to make proper
JSON-style YAML bindings for the top level.
Cc: devicetree@vger.kernel.org
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
This adds device tree probe and registration support for
the IXP4xx GPIO driver.
Cc: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
This adds support for setting up the IXP4xx timer driver from
device tree.
Cc: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
This adds device tree bindings for the Intel IXP4xx
timers.
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: devicetree@vger.kernel.org
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
This adds support for probing and settin up the IXP4xx
irqchip from device tree.
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
This adds device tree bindings for the IXP4xx interrupt
controller. It's a standard 2-cell controller.
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: devicetree@vger.kernel.org
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
This augments the IXP4xx to select and use the new
timer driver in drivers/clocksource and removes the old
code in the machine.
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
This adds a new slightly rewritten timer driver for the
Intel IXP4xx clocksource, clockevent and delay timer.
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
This deletes the old irq+gpiochip combo from the IXP4xx
machine and switches it over to use the new drivers merged
in respective subsystem.
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
This adds a driver for the IXP4xx GPIO block found in
the Intel XScale IXP4xx systems.
The GPIO part of this block is pretty straight-forward and
just uses the generic MMIO GPIO library.
The irqchip side of this driver is hierarchical where
the main irqchip will receive a processed level trigger
in response to the edge detector of the GPIO block,
so for this reason the v2 version of the irqdomain API
is used (as well as in the parent IXP4xx irqchip) and
masking, unmasking and setting up the type on IRQ
happens on several levels.
Currently this GPIO controller will grab the parent
irqdomain using a special function, but as the platform
move toward device tree probing, this will not be needed:
we can just look up the parent irqdomain from the device
tree.
Cc: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
bio_add_page() and __bio_add_page() are capable of adding pages into
bio, and now we have at least two such usages alreay:
- __bio_iov_bvec_add_pages()
- nvmet_bdev_execute_rw().
So update comments on these two helpers.
The thing is a bit special for __bio_try_merge_page(), given the caller
needs to know if the new added page is same with the last added page,
then it isn't safe to pass multi-page in case that 'same_page' is true,
so adds warning on potential misuse, and updates comment on
__bio_try_merge_page().
Cc: linux-xfs@vger.kernel.org
Cc: linux-fsdevel@vger.kernel.org
Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The call to thermal_cdev_update() causes any fan connected to the chip
to stop immediately. If the thermal subsystem is not set up to actually
handle the chip as cooling device, the remains stopped until is is
restarted manually with a write to a sysfs attribute.
There is evidence that thermal_cdev_update() should only be called from
thermal governors, not from thermal cooling device drivers. Drop the call.
Cc: Jean-Francois Dagenais <jeff.dagenais@gmail.com>
Tested-by: Jean-Francois Dagenais <jeff.dagenais@gmail.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Although not likely, the bundle allocation might fail.
Add proper error check and warning print.
Signed-off-by: Erik Stromdahl <erik.stromdahl@gmail.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
HTC header carries junk values that may be interpreted by the firmware
differently. Enable credit update only if flow control is enabled for
the corresponding endpoint.
Signed-off-by: Alagu Sankar <alagusankar@silex-india.com>
Signed-off-by: Erik Stromdahl <erik.stromdahl@gmail.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
With SDIO there's a use after free after a data frame is transfered, call stack
below. This happens because ath10k_htt_tx_hl() directly transmits the skb
provided by mac80211 using ath10k_htc_send(), all other HTT functions use
separate skb created with ath10k_htc_alloc_skb() to transmit the HTC packet.
After the packet is transmitted mac80211 frees the skb in ieee80211_tx_status()
but HTT layer expects that it still owns the skb, and frees it in
ath10k_htt_htc_tx_complete().
To fix this take a reference of skb before sending it to HTC layer to make sure
we still own the skb.
Tested on QCA6174 SDIO with firmware WLAN.RMH.4.4.1-00007-QCARMSWP-1.
ath10k_htt_tx_hl() is only used by SDIO and USB so other busses (PCI, AHB and
SNOC) should be unaffected.
call stack of use-after-free:
dump_backtrace+0x0/0x2d8
show_stack+0x20/0x2c
__dump_stack+0x20/0x28
dump_stack+0xc8/0xec
print_address_description+0x74/0x240
kasan_report+0x258/0x274
__asan_report_load4_noabort+0x20/0x28
skb_pull+0xbc/0x114
ath10k_htc_notify_tx_completion+0x190/0x2a4 [ath10k_core]
ath10k_sdio_write_async_work+0x1e4/0x2c4 [ath10k_sdio]
process_one_work+0x3d8/0x8b0
worker_thread+0x518/0x7e0
kthread+0x260/0x278
ret_from_fork+0x10/0x18
Allocated by one task:
kasan_kmalloc+0xa0/0x13c
kasan_slab_alloc+0x14/0x1c
kmem_cache_alloc+0x144/0x208
__alloc_skb+0xec/0x394
alloc_skb_with_frags+0x8c/0x374
sock_alloc_send_pskb+0x520/0x5d4
sock_alloc_send_skb+0x40/0x50
__ip_append_data+0xf5c/0x1858
ip_make_skb+0x194/0x1d4
udp_sendmsg+0xf24/0x1ab8
inet_sendmsg+0x1b0/0x2e0
sock_sendmsg+0x88/0xa0
__sys_sendto+0x220/0x3a8
__arm64_sys_sendto+0x78/0x80
el0_svc_common+0x120/0x1e0
el0_svc_compat_handler+0x64/0x80
el0_svc_compat+0x8/0x18
Freed by another task:
__kasan_slab_free+0x120/0x1d4
kasan_slab_free+0x10/0x1c
kmem_cache_free+0x74/0x504
kfree_skbmem+0x88/0xc8
__kfree_skb+0x24/0x2c
consume_skb+0x114/0x18c
__ieee80211_tx_status+0xb7c/0xf60 [mac80211]
ieee80211_tx_status+0x224/0x270 [mac80211]
ath10k_txrx_tx_unref+0x564/0x950 [ath10k_core]
ath10k_htt_t2h_msg_handler+0x178c/0x2a38 [ath10k_core]
ath10k_htt_htc_t2h_msg_handler+0x20/0x30 [ath10k_core]
ath10k_sdio_irq_handler+0xcc0/0x1654 [ath10k_sdio]
process_sdio_pending_irqs+0xec/0x358
sdio_run_irqs+0x68/0xe4
sdio_irq_work+0x1c/0x28
process_one_work+0x3d8/0x8b0
worker_thread+0x518/0x7e0
kthread+0x260/0x278
ret_from_fork+0x10/0x18
Reported-by: Wen Gong <wgong@codeaurora.org>
Tested-by: Wen Gong <wgong@codeaurora.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Transmit completion for SDIO is similar to PCIe, modify the high
latency path to allow SDIO modules to use the msdu id.
kvalo: the original patch from Alagu enabled this only for SDIO but I'm not
sure should we also enable this with USB. I'll use bus params to enable this
for so that it's easy to enable also for USB later.
Tested with QCA6174 SDIO with firmware WLAN.RMH.4.4.1-00007-QCARMSWP-1.
Co-developed-by: Wen Gong <wgong@codeaurora.org>
Signed-off-by: Alagu Sankar <alagusankar@silex-india.com>
Signed-off-by: Wen Gong <wgong@codeaurora.org>.
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
This way we don't need to set every variable and give them to default, which is
zero. This is also safer in case we forgot to initalise a new field in some of
the bus modules.
Compile tested only.
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
HTT High Latency (ATH10K_DEV_TYPE_HL) does not use txdone_fifo at all, we don't
even initialise it by skipping ath10k_htt_tx_alloc_buf() in
ath10k_htt_tx_start(). Because of this using QCA6174 SDIO
ath10k_htt_rx_tx_compl_ind() will crash when it accesses unitialised
txdone_fifo. So skip txdone_fifo when using High Latency mode.
Tested with QCA6174 SDIO with firmware WLAN.RMH.4.4.1-00007-QCARMSWP-1.
Co-developed-by: Wen Gong <wgong@codeaurora.org>
Signed-off-by: Alagu Sankar <alagusankar@silex-india.com>
Signed-off-by: Wen Gong <wgong@codeaurora.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Disabling interrupts this early meant WMI communication was not working anymore
when the SDIO device was removed. But we call ath10k_core_unregister() that
will eventually call ath10k_sdio_hif_stop(), which disables the interrupts. So
there's actually no need to disable interrupts here.
Also remove cancel_work_sync() as it's also called in ath10k_sdio_hif_stop().
Tested with QCA6174 SDIO with firmware WLAN.RMH.4.4.1-00007-QCARMSWP-1.
Signed-off-by: Wen Gong <wgong@codeaurora.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
On QCA6174 SDIO devices the SDIO interrupt will fail if UART is
disabled from ath10k. SDIO firmware enables UART printouts by
default. If ath10k will try to enable UART again the firmware
will configure it's GPIO line incorrectly and SDIO interrupts
won't work anymore. The workaround is to set UART pin again (19
for QCA6174 SDIO) if uart_print is 0.
Tested with QCA6174 SDIO with firmware WLAN.RMH.4.4.1-00007-QCARMSWP-1.
Signed-off-by: Wen Gong <wgong@codeaurora.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
In order to make sure that the plane color space gets reset correctly.
Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Initialize the flow input colorspaces to unknown and reset to that value
when the channel gets disabled. This avoids the state getting mixed up
with a previous mode.
Also keep the CSC settings for the background flow intact when disabling
the foreground flow.
Root-caused-by: Jonathan Marek <jonathan@marek.ca>
Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Another bodge for the ftrace PLT code: plt_entries_equal() now takes
the place relative nature of the ADRP/ADD based PLT entries into
account, which means that a struct trampoline instance on the stack
is no longer equal to the same set of opcodes in the module struct,
given that they don't point to the same place in memory anymore.
Work around this by using memcmp() in the ftrace PLT handling code.
Acked-by: Will Deacon <will.deacon@arm.com>
Tested-by: dann frazier <dann.frazier@canonical.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
The revised I/O ordering section of memory-barriers.txt introduced in
4614bbdee3 ("docs/memory-barriers.txt: Rewrite "KERNEL I/O BARRIER
EFFECTS" section") loosely refers to "the CPU", whereas the ordering
guarantees generally apply within a thread of execution that can migrate
between cores, with the scheduler providing the relevant barrier
semantics.
Reword the section to refer to "CPU thread" and call out ordering of
MMIO writes separately from ordering of writes to memory. Ben also
spotted that the string accessors are native-endian, so fix that up too.
Link: https://lkml.kernel.org/r/080d1ec73e3e29d6ffeeeb50b39b613da28afb37.camel@kernel.crashing.org
Fixes: 4614bbdee3 ("docs/memory-barriers.txt: Rewrite "KERNEL I/O BARRIER EFFECTS" section")
Reported-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
