tjh.dev
Linux kernel
============
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several of them using the Restructured Text markup notation.
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requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.
Linux kernel mirror (for testing)
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Fix the following sparse warning:
drivers/irqchip/irq-bcm7038-l1.c:419:12: warning: symbol
'bcm7038_l1_of_init' was not declared. Should it be static?
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Jason Yan <yanaijie@huawei.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20200417074036.46594-1-yanaijie@huawei.com
Although the vSGIs are not directly visible to the host, they still
get moved around by the CPU hotplug, for example. This results in
the kernel moaning on the console, such as:
genirq: irq_chip GICv4.1-sgi did not update eff. affinity mask of irq 38
Updating the effective affinity on set_affinity() fixes it.
Reviewed-by: Zenghui Yu <yuzenghui@huawei.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Fix the following sparse warning:
drivers/irqchip/irq-mvebu-icu.c:69:1: warning: symbol 'legacy_bindings'
was not declared. Should it be static?
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Jason Yan <yanaijie@huawei.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20200417074046.46771-1-yanaijie@huawei.com
When a vPE is made resident, the GIC starts parsing the virtual pending
table to deliver pending interrupts. This takes place asynchronously,
and can at times take a long while. Long enough that the vcpu enters
the guest and hits WFI before any interrupt has been signaled yet.
The vcpu then exits, blocks, and now gets a doorbell. Rince, repeat.
In order to avoid the above, a (optional on GICv4, mandatory on v4.1)
feature allows the GIC to feedback to the hypervisor whether it is
done parsing the VPT by clearing the GICR_VPENDBASER.Dirty bit.
The hypervisor can then wait until the GIC is ready before actually
running the vPE.
Plug the detection code as well as polling on vPE schedule. While
at it, tidy-up the kernel message that displays the GICv4 optional
features.
Reviewed-by: Zenghui Yu <yuzenghui@huawei.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Running a lockedp-enabled kernel on a vim3l board (Amlogic SM1)
leads to the following splat:
[ 13.557138] WARNING: HARDIRQ-safe -> HARDIRQ-unsafe lock order detected
[ 13.587485] ip/456 [HC0[0]:SC0[0]:HE0:SE1] is trying to acquire:
[ 13.625922] ffff000059908cf0 (&irq_desc_lock_class){-.-.}-{2:2}, at: __setup_irq+0xf8/0x8d8
[ 13.632273] which would create a new lock dependency:
[ 13.637272] (&irq_desc_lock_class){-.-.}-{2:2} -> (&ctl->lock){+.+.}-{2:2}
[ 13.644209]
[ 13.644209] but this new dependency connects a HARDIRQ-irq-safe lock:
[ 13.654122] (&irq_desc_lock_class){-.-.}-{2:2}
[ 13.654125]
[ 13.654125] ... which became HARDIRQ-irq-safe at:
[ 13.664759] lock_acquire+0xec/0x368
[ 13.666926] _raw_spin_lock+0x60/0x88
[ 13.669979] handle_fasteoi_irq+0x30/0x178
[ 13.674082] generic_handle_irq+0x38/0x50
[ 13.678098] __handle_domain_irq+0x6c/0xc8
[ 13.682209] gic_handle_irq+0x5c/0xb0
[ 13.685872] el1_irq+0xd0/0x180
[ 13.689010] arch_cpu_idle+0x40/0x220
[ 13.692732] default_idle_call+0x54/0x60
[ 13.696677] do_idle+0x23c/0x2e8
[ 13.699903] cpu_startup_entry+0x30/0x50
[ 13.703852] rest_init+0x1e0/0x2b4
[ 13.707301] arch_call_rest_init+0x18/0x24
[ 13.711449] start_kernel+0x4ec/0x51c
[ 13.715167]
[ 13.715167] to a HARDIRQ-irq-unsafe lock:
[ 13.722426] (&ctl->lock){+.+.}-{2:2}
[ 13.722430]
[ 13.722430] ... which became HARDIRQ-irq-unsafe at:
[ 13.732319] ...
[ 13.732324] lock_acquire+0xec/0x368
[ 13.735985] _raw_spin_lock+0x60/0x88
[ 13.739452] meson_gpio_irq_domain_alloc+0xcc/0x290
[ 13.744392] irq_domain_alloc_irqs_hierarchy+0x24/0x60
[ 13.749586] __irq_domain_alloc_irqs+0x160/0x2f0
[ 13.754254] irq_create_fwspec_mapping+0x118/0x320
[ 13.759073] irq_create_of_mapping+0x78/0xa0
[ 13.763360] of_irq_get+0x6c/0x80
[ 13.766701] of_mdiobus_register_phy+0x10c/0x238 [of_mdio]
[ 13.772227] of_mdiobus_register+0x158/0x380 [of_mdio]
[ 13.777388] mdio_mux_init+0x180/0x2e8 [mdio_mux]
[ 13.782128] g12a_mdio_mux_probe+0x290/0x398 [mdio_mux_meson_g12a]
[ 13.788349] platform_drv_probe+0x5c/0xb0
[ 13.792379] really_probe+0xe4/0x448
[ 13.795979] driver_probe_device+0xe8/0x140
[ 13.800189] __device_attach_driver+0x94/0x120
[ 13.804639] bus_for_each_drv+0x84/0xd8
[ 13.808474] __device_attach+0xe4/0x168
[ 13.812361] device_initial_probe+0x1c/0x28
[ 13.816592] bus_probe_device+0xa4/0xb0
[ 13.820430] deferred_probe_work_func+0xa8/0x100
[ 13.825064] process_one_work+0x264/0x688
[ 13.829088] worker_thread+0x4c/0x458
[ 13.832768] kthread+0x154/0x158
[ 13.836018] ret_from_fork+0x10/0x18
[ 13.839612]
[ 13.839612] other info that might help us debug this:
[ 13.839612]
[ 13.850354] Possible interrupt unsafe locking scenario:
[ 13.850354]
[ 13.855720] CPU0 CPU1
[ 13.858774] ---- ----
[ 13.863242] lock(&ctl->lock);
[ 13.866330] local_irq_disable();
[ 13.872233] lock(&irq_desc_lock_class);
[ 13.878705] lock(&ctl->lock);
[ 13.884297] <Interrupt>
[ 13.886857] lock(&irq_desc_lock_class);
[ 13.891014]
[ 13.891014] *** DEADLOCK ***
The issue can occur when CPU1 is doing something like irq_set_type()
and CPU0 performing an interrupt allocation, for example. Taking
an interrupt (like the one being reconfigured) would lead to a deadlock.
A solution to this is:
- Reorder the locking so that meson_gpio_irq_update_bits takes the lock
itself at all times, instead of relying on the caller to lock or not,
hence making the RMW sequence atomic,
- Rework the critical section in meson_gpio_irq_request_channel to only
cover the allocation itself, and let the gpio_irq_sel_pin callback
deal with its own locking if required,
- Take the private spin-lock with interrupts disabled at all times
Reviewed-by: Jerome Brunet <jbrunet@baylibre.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
As per the PLIC specification, maximum priority threshold value is 0x7
not 0xF. Even though it doesn't cause any error in qemu/hifive unleashed,
there may be some implementation which checks the upper bound resulting in
an illegal access.
Fixes: ccbe80bad571 ("irqchip/sifive-plic: Enable/Disable external interrupts upon cpu online/offline")
Signed-off-by: Atish Patra <atish.patra@wdc.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20200403014609.71831-1-atish.patra@wdc.com
This sorts the actual field names too, potentially causing even more
chaos and confusion at merge time if you have edited the MAINTAINERS
file. But the end result is a more consistent layout, and hopefully
it's a one-time pain minimized by doing this just before the -rc1
release.
This was entirely scripted:
./scripts/parse-maintainers.pl --input=MAINTAINERS --output=MAINTAINERS --order
Requested-by: Joe Perches <joe@perches.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The ti_sci_inta_irq_handler() does not take into account INTA IRQs state
(masked/unmasked) as it uses INTA_STATUS_CLEAR_j register to get INTA IRQs
status, which provides raw status value.
This causes hard IRQ handlers to be called or threaded handlers to be
scheduled many times even if corresponding INTA IRQ is masked.
Above, first of all, affects the LEVEL interrupts processing and causes
unexpected behavior up the system stack or crash.
Fix it by using the Interrupt Masked Status INTA_STATUSM_j register which
provides masked INTA IRQs status.
Fixes: 9f1463b86c13 ("irqchip/ti-sci-inta: Add support for Interrupt Aggregator driver")
Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Lokesh Vutla <lokeshvutla@ti.com>
Link: https://lore.kernel.org/r/20200408191532.31252-1-grygorii.strashko@ti.com
Cc: stable@vger.kernel.org
They are all supposed to be sorted, but people who add new entries don't
always know the alphabet. Plus sometimes the entry names get edited,
and people don't then re-order the entry.
Let's see how painful this will be for merging purposes (the MAINTAINERS
file is often edited in various different trees), but Joe claims there's
relatively few patches in -next that touch this, and doing it just
before -rc1 is likely the best time. Fingers crossed.
This was scripted with
/scripts/parse-maintainers.pl --input=MAINTAINERS --output=MAINTAINERS
but then I also ended up manually upper-casing a few entry names that
stood out when looking at the end result.
Requested-by: Joe Perches <joe@perches.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Using irq_domain_free_irqs_common() on the irqdomain free path will
leave the MSI descriptor unfreed when platform devices get removed.
Properly free it by MSI domain free function.
Fixes: 9650c60ebfec0 ("irqchip/mbigen: Create irq domain for each mbigen device")
Signed-off-by: Zenghui Yu <yuzenghui@huawei.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20200408114352.1604-1-yuzenghui@huawei.com
Pull x86 fixes from Thomas Gleixner:
"A set of three patches to fix the fallout of the newly added split
lock detection feature.
It addressed the case where a KVM guest triggers a split lock #AC and
KVM reinjects it into the guest which is not prepared to handle it.
Add proper sanity checks which prevent the unconditional injection
into the guest and handles the #AC on the host side in the same way as
user space detections are handled. Depending on the detection mode it
either warns and disables detection for the task or kills the task if
the mode is set to fatal"
* tag 'x86-urgent-2020-04-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
KVM: VMX: Extend VMXs #AC interceptor to handle split lock #AC in guest
KVM: x86: Emulate split-lock access as a write in emulator
x86/split_lock: Provide handle_guest_split_lock()
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