linux-stable.git/drivers/irqchip, branch v5.4.78 Linux kernel stable tree irqchip/stm32-exti: Avoid losing interrupts due to clearing pending bits by mistake 2020-09-03T09:27:06+00:00 qiuguorui1 qiuguorui1@huawei.com 2020-08-20T03:16:29+00:00 47c8387a963e5c2061a27ea3dfee0609268e83e9 commit e579076ac0a3bebb440fab101aef3c42c9f4c709 upstream. In the current code, when the eoi callback of the exti clears the pending bit of the current interrupt, it will first read the values of fpr and rpr, then logically OR the corresponding bit of the interrupt number, and finally write back to fpr and rpr. We found through experiments that if two exti interrupts, we call them int1/int2, arrive almost at the same time. in our scenario, the time difference is 30 microseconds, assuming int1 is triggered first. there will be an extreme scenario: both int's pending bit are set to 1, the irq handle of int1 is executed first, and eoi handle is then executed, at this moment, all pending bits are cleared, but the int 2 has not finally been reported to the cpu yet, which eventually lost int2. According to stm32's TRM description about rpr and fpr: Writing a 1 to this bit will trigger a rising edge event on event x, Writing 0 has no effect. Therefore, when clearing the pending bit, we only need to clear the pending bit of the irq. Fixes: 927abfc4461e7 ("irqchip/stm32: Add stm32mp1 support with hierarchy domain") Signed-off-by: qiuguorui1 <qiuguorui1@huawei.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Cc: stable@vger.kernel.org # v4.18+ Link: https://lore.kernel.org/r/20200820031629.15582-1-qiuguorui1@huawei.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit e579076ac0a3bebb440fab101aef3c42c9f4c709 upstream.

In the current code, when the eoi callback of the exti clears the pending
bit of the current interrupt, it will first read the values of fpr and
rpr, then logically OR the corresponding bit of the interrupt number,
and finally write back to fpr and rpr.

We found through experiments that if two exti interrupts,
we call them int1/int2, arrive almost at the same time. in our scenario,
the time difference is 30 microseconds, assuming int1 is triggered first.

there will be an extreme scenario: both int's pending bit are set to 1,
the irq handle of int1 is executed first, and eoi handle is then executed,
at this moment, all pending bits are cleared, but the int 2 has not
finally been reported to the cpu yet, which eventually lost int2.

According to stm32's TRM description about rpr and fpr: Writing a 1 to this
bit will trigger a rising edge event on event x, Writing 0 has no
effect.

Therefore, when clearing the pending bit, we only need to clear the
pending bit of the irq.

Fixes: 927abfc4461e7 ("irqchip/stm32: Add stm32mp1 support with hierarchy domain")
Signed-off-by: qiuguorui1 <qiuguorui1@huawei.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Cc: stable@vger.kernel.org # v4.18+
Link: https://lore.kernel.org/r/20200820031629.15582-1-qiuguorui1@huawei.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
genirq/affinity: Make affinity setting if activated opt-in 2020-08-21T11:05:20+00:00 Thomas Gleixner tglx@linutronix.de 2020-07-24T20:44:41+00:00 a11f42496ac80813d94b30d51868d4610bb5e5d9 commit f0c7baca180046824e07fc5f1326e83a8fd150c7 upstream. John reported that on a RK3288 system the perf per CPU interrupts are all affine to CPU0 and provided the analysis: "It looks like what happens is that because the interrupts are not per-CPU in the hardware, armpmu_request_irq() calls irq_force_affinity() while the interrupt is deactivated and then request_irq() with IRQF_PERCPU | IRQF_NOBALANCING. Now when irq_startup() runs with IRQ_STARTUP_NORMAL, it calls irq_setup_affinity() which returns early because IRQF_PERCPU and IRQF_NOBALANCING are set, leaving the interrupt on its original CPU." This was broken by the recent commit which blocked interrupt affinity setting in hardware before activation of the interrupt. While this works in general, it does not work for this particular case. As contrary to the initial analysis not all interrupt chip drivers implement an activate callback, the safe cure is to make the deferred interrupt affinity setting at activation time opt-in. Implement the necessary core logic and make the two irqchip implementations for which this is required opt-in. In hindsight this would have been the right thing to do, but ... Fixes: baedb87d1b53 ("genirq/affinity: Handle affinity setting on inactive interrupts correctly") Reported-by: John Keeping <john@metanate.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Marc Zyngier <maz@kernel.org> Acked-by: Marc Zyngier <maz@kernel.org> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/87blk4tzgm.fsf@nanos.tec.linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit f0c7baca180046824e07fc5f1326e83a8fd150c7 upstream.

John reported that on a RK3288 system the perf per CPU interrupts are all
affine to CPU0 and provided the analysis:

 "It looks like what happens is that because the interrupts are not per-CPU
  in the hardware, armpmu_request_irq() calls irq_force_affinity() while
  the interrupt is deactivated and then request_irq() with IRQF_PERCPU |
  IRQF_NOBALANCING.

  Now when irq_startup() runs with IRQ_STARTUP_NORMAL, it calls
  irq_setup_affinity() which returns early because IRQF_PERCPU and
  IRQF_NOBALANCING are set, leaving the interrupt on its original CPU."

This was broken by the recent commit which blocked interrupt affinity
setting in hardware before activation of the interrupt. While this works in
general, it does not work for this particular case. As contrary to the
initial analysis not all interrupt chip drivers implement an activate
callback, the safe cure is to make the deferred interrupt affinity setting
at activation time opt-in.

Implement the necessary core logic and make the two irqchip implementations
for which this is required opt-in. In hindsight this would have been the
right thing to do, but ...

Fixes: baedb87d1b53 ("genirq/affinity: Handle affinity setting on inactive interrupts correctly")
Reported-by: John Keeping <john@metanate.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Marc Zyngier <maz@kernel.org>
Acked-by: Marc Zyngier <maz@kernel.org>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/87blk4tzgm.fsf@nanos.tec.linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
irqchip/irq-mtk-sysirq: Replace spinlock with raw_spinlock 2020-08-19T06:16:02+00:00 Bartosz Golaszewski bgolaszewski@baylibre.com 2020-06-15T07:44:45+00:00 ae3033d3859691136642ca01e8fdae2a05ffcd3c [ Upstream commit 6eeb997ab5075e770a002c51351fa4ec2c6b5c39 ] This driver may take a regular spinlock when a raw spinlock (irq_desc->lock) is already taken which results in the following lockdep splat: ============================= [ BUG: Invalid wait context ] 5.7.0-rc7 #1 Not tainted ----------------------------- swapper/0/0 is trying to lock: ffffff800303b798 (&chip_data->lock){....}-{3:3}, at: mtk_sysirq_set_type+0x48/0xc0 other info that might help us debug this: context-{5:5} 2 locks held by swapper/0/0: #0: ffffff800302ee68 (&desc->request_mutex){....}-{4:4}, at: __setup_irq+0xc4/0x8a0 #1: ffffff800302ecf0 (&irq_desc_lock_class){....}-{2:2}, at: __setup_irq+0xe4/0x8a0 stack backtrace: CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.7.0-rc7 #1 Hardware name: Pumpkin MT8516 (DT) Call trace: dump_backtrace+0x0/0x180 show_stack+0x14/0x20 dump_stack+0xd0/0x118 __lock_acquire+0x8c8/0x2270 lock_acquire+0xf8/0x470 _raw_spin_lock_irqsave+0x50/0x78 mtk_sysirq_set_type+0x48/0xc0 __irq_set_trigger+0x58/0x170 __setup_irq+0x420/0x8a0 request_threaded_irq+0xd8/0x190 timer_of_init+0x1e8/0x2c4 mtk_gpt_init+0x5c/0x1dc timer_probe+0x74/0xf4 time_init+0x14/0x44 start_kernel+0x394/0x4f0 Replace the spinlock_t with raw_spinlock_t to avoid this warning. Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20200615074445.3579-1-brgl@bgdev.pl Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 6eeb997ab5075e770a002c51351fa4ec2c6b5c39 ]

This driver may take a regular spinlock when a raw spinlock
(irq_desc->lock) is already taken which results in the following
lockdep splat:

=============================
[ BUG: Invalid wait context ]
5.7.0-rc7 #1 Not tainted
-----------------------------
swapper/0/0 is trying to lock:
ffffff800303b798 (&chip_data->lock){....}-{3:3}, at: mtk_sysirq_set_type+0x48/0xc0
other info that might help us debug this:
context-{5:5}
2 locks held by swapper/0/0:
 #0: ffffff800302ee68 (&desc->request_mutex){....}-{4:4}, at: __setup_irq+0xc4/0x8a0
 #1: ffffff800302ecf0 (&irq_desc_lock_class){....}-{2:2}, at: __setup_irq+0xe4/0x8a0
stack backtrace:
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.7.0-rc7 #1
Hardware name: Pumpkin MT8516 (DT)
Call trace:
 dump_backtrace+0x0/0x180
 show_stack+0x14/0x20
 dump_stack+0xd0/0x118
 __lock_acquire+0x8c8/0x2270
 lock_acquire+0xf8/0x470
 _raw_spin_lock_irqsave+0x50/0x78
 mtk_sysirq_set_type+0x48/0xc0
 __irq_set_trigger+0x58/0x170
 __setup_irq+0x420/0x8a0
 request_threaded_irq+0xd8/0x190
 timer_of_init+0x1e8/0x2c4
 mtk_gpt_init+0x5c/0x1dc
 timer_probe+0x74/0xf4
 time_init+0x14/0x44
 start_kernel+0x394/0x4f0

Replace the spinlock_t with raw_spinlock_t to avoid this warning.

Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20200615074445.3579-1-brgl@bgdev.pl
Signed-off-by: Sasha Levin <sashal@kernel.org>
irqchip/ti-sci-inta: Fix return value about devm_ioremap_resource() 2020-08-19T06:15:58+00:00 Tiezhu Yang yangtiezhu@loongson.cn 2020-06-06T09:50:16+00:00 7915a3c04139cb44d26d8de3aed8abbfc735586f [ Upstream commit 4b127a14cb1385dd355c7673d975258d5d668922 ] When call function devm_ioremap_resource(), we should use IS_ERR() to check the return value and return PTR_ERR() if failed. Fixes: 9f1463b86c13 ("irqchip/ti-sci-inta: Add support for Interrupt Aggregator driver") Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn> Signed-off-by: Marc Zyngier <maz@kernel.org> Reviewed-by: Grygorii Strashko <grygorii.strashko@ti.com> Link: https://lore.kernel.org/r/1591437017-5295-2-git-send-email-yangtiezhu@loongson.cn Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 4b127a14cb1385dd355c7673d975258d5d668922 ]

When call function devm_ioremap_resource(), we should use IS_ERR()
to check the return value and return PTR_ERR() if failed.

Fixes: 9f1463b86c13 ("irqchip/ti-sci-inta: Add support for Interrupt Aggregator driver")
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Grygorii Strashko <grygorii.strashko@ti.com>
Link: https://lore.kernel.org/r/1591437017-5295-2-git-send-email-yangtiezhu@loongson.cn
Signed-off-by: Sasha Levin <sashal@kernel.org>
irqchip/gic: Atomically update affinity 2020-07-09T07:37:56+00:00 Marc Zyngier maz@kernel.org 2020-06-21T13:43:15+00:00 2a9278ac9c5515b372fbc831d7b0702096dc3127 commit 005c34ae4b44f085120d7f371121ec7ded677761 upstream. The GIC driver uses a RMW sequence to update the affinity, and relies on the gic_lock_irqsave/gic_unlock_irqrestore sequences to update it atomically. But these sequences only expand into anything meaningful if the BL_SWITCHER option is selected, which almost never happens. It also turns out that using a RMW and locks is just as silly, as the GIC distributor supports byte accesses for the GICD_TARGETRn registers, which when used make the update atomic by definition. Drop the terminally broken code and replace it by a byte write. Fixes: 04c8b0f82c7d ("irqchip/gic: Make locking a BL_SWITCHER only feature") Cc: stable@vger.kernel.org Signed-off-by: Marc Zyngier <maz@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 005c34ae4b44f085120d7f371121ec7ded677761 upstream.

The GIC driver uses a RMW sequence to update the affinity, and
relies on the gic_lock_irqsave/gic_unlock_irqrestore sequences
to update it atomically.

But these sequences only expand into anything meaningful if
the BL_SWITCHER option is selected, which almost never happens.

It also turns out that using a RMW and locks is just as silly,
as the GIC distributor supports byte accesses for the GICD_TARGETRn
registers, which when used make the update atomic by definition.

Drop the terminally broken code and replace it by a byte write.

Fixes: 04c8b0f82c7d ("irqchip/gic: Make locking a BL_SWITCHER only feature")
Cc: stable@vger.kernel.org
Signed-off-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
irqchip/mbigen: Free msi_desc on device teardown 2020-04-23T08:36:20+00:00 Zenghui Yu yuzenghui@huawei.com 2020-04-08T11:43:52+00:00 182fa4d72a7c128a4b02b6a702eb75f8862d5382 commit edfc23f6f9fdbd7825d50ac1f380243cde19b679 upstream. 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 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit edfc23f6f9fdbd7825d50ac1f380243cde19b679 upstream.

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
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
irqchip/ti-sci-inta: Fix processing of masked irqs 2020-04-21T07:05:03+00:00 Grygorii Strashko grygorii.strashko@ti.com 2020-04-08T19:15:32+00:00 6b5e8e7cbe242183ab9f8298c8644fcfe6182a96 commit 3688b0db5c331f4ec3fa5eb9f670a4b04f530700 upstream. 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 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 3688b0db5c331f4ec3fa5eb9f670a4b04f530700 upstream.

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
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
irqchip/versatile-fpga: Apply clear-mask earlier 2020-04-17T08:50:11+00:00 Sungbo Eo mans0n@gorani.run 2020-03-21T13:38:42+00:00 6124e10dbc4ff68f3442f7dae845912d085f80fc commit 6a214a28132f19ace3d835a6d8f6422ec80ad200 upstream. Clear its own IRQs before the parent IRQ get enabled, so that the remaining IRQs do not accidentally interrupt the parent IRQ controller. This patch also fixes a reboot bug on OX820 SoC, where the remaining rps-timer IRQ raises a GIC interrupt that is left pending. After that, the rps-timer IRQ is cleared during driver initialization, and there's no IRQ left in rps-irq when local_irq_enable() is called, which evokes an error message "unexpected IRQ trap". Fixes: bdd272cbb97a ("irqchip: versatile FPGA: support cascaded interrupts from DT") Signed-off-by: Sungbo Eo <mans0n@gorani.run> Signed-off-by: Marc Zyngier <maz@kernel.org> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20200321133842.2408823-1-mans0n@gorani.run Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 6a214a28132f19ace3d835a6d8f6422ec80ad200 upstream.

Clear its own IRQs before the parent IRQ get enabled, so that the
remaining IRQs do not accidentally interrupt the parent IRQ controller.

This patch also fixes a reboot bug on OX820 SoC, where the remaining
rps-timer IRQ raises a GIC interrupt that is left pending. After that,
the rps-timer IRQ is cleared during driver initialization, and there's
no IRQ left in rps-irq when local_irq_enable() is called, which evokes
an error message "unexpected IRQ trap".

Fixes: bdd272cbb97a ("irqchip: versatile FPGA: support cascaded interrupts from DT")
Signed-off-by: Sungbo Eo <mans0n@gorani.run>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20200321133842.2408823-1-mans0n@gorani.run
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
irqchip/gic-v4: Provide irq_retrigger to avoid circular locking dependency 2020-04-17T08:50:04+00:00 Marc Zyngier maz@kernel.org 2020-03-10T18:49:21+00:00 6420b2e5fa664450542f290df7b7848dc2e71309 [ Upstream commit 7809f7011c3bce650e502a98afeb05961470d865 ] On a very heavily loaded D05 with GICv4, I managed to trigger the following lockdep splat: [ 6022.598864] ====================================================== [ 6022.605031] WARNING: possible circular locking dependency detected [ 6022.611200] 5.6.0-rc4-00026-geee7c7b0f498 #680 Tainted: G E [ 6022.618061] ------------------------------------------------------ [ 6022.624227] qemu-system-aar/7569 is trying to acquire lock: [ 6022.629789] ffff042f97606808 (&p->pi_lock){-.-.}, at: try_to_wake_up+0x54/0x7a0 [ 6022.637102] [ 6022.637102] but task is already holding lock: [ 6022.642921] ffff002fae424cf0 (&irq_desc_lock_class){-.-.}, at: __irq_get_desc_lock+0x5c/0x98 [ 6022.651350] [ 6022.651350] which lock already depends on the new lock. [ 6022.651350] [ 6022.659512] [ 6022.659512] the existing dependency chain (in reverse order) is: [ 6022.666980] [ 6022.666980] -> #2 (&irq_desc_lock_class){-.-.}: [ 6022.672983] _raw_spin_lock_irqsave+0x50/0x78 [ 6022.677848] __irq_get_desc_lock+0x5c/0x98 [ 6022.682453] irq_set_vcpu_affinity+0x40/0xc0 [ 6022.687236] its_make_vpe_non_resident+0x6c/0xb8 [ 6022.692364] vgic_v4_put+0x54/0x70 [ 6022.696273] vgic_v3_put+0x20/0xd8 [ 6022.700183] kvm_vgic_put+0x30/0x48 [ 6022.704182] kvm_arch_vcpu_put+0x34/0x50 [ 6022.708614] kvm_sched_out+0x34/0x50 [ 6022.712700] __schedule+0x4bc/0x7f8 [ 6022.716697] schedule+0x50/0xd8 [ 6022.720347] kvm_arch_vcpu_ioctl_run+0x5f0/0x978 [ 6022.725473] kvm_vcpu_ioctl+0x3d4/0x8f8 [ 6022.729820] ksys_ioctl+0x90/0xd0 [ 6022.733642] __arm64_sys_ioctl+0x24/0x30 [ 6022.738074] el0_svc_common.constprop.3+0xa8/0x1e8 [ 6022.743373] do_el0_svc+0x28/0x88 [ 6022.747198] el0_svc+0x14/0x40 [ 6022.750761] el0_sync_handler+0x124/0x2b8 [ 6022.755278] el0_sync+0x140/0x180 [ 6022.759100] [ 6022.759100] -> #1 (&rq->lock){-.-.}: [ 6022.764143] _raw_spin_lock+0x38/0x50 [ 6022.768314] task_fork_fair+0x40/0x128 [ 6022.772572] sched_fork+0xe0/0x210 [ 6022.776484] copy_process+0x8c4/0x18d8 [ 6022.780742] _do_fork+0x88/0x6d8 [ 6022.784478] kernel_thread+0x64/0x88 [ 6022.788563] rest_init+0x30/0x270 [ 6022.792390] arch_call_rest_init+0x14/0x1c [ 6022.796995] start_kernel+0x498/0x4c4 [ 6022.801164] [ 6022.801164] -> #0 (&p->pi_lock){-.-.}: [ 6022.806382] __lock_acquire+0xdd8/0x15c8 [ 6022.810813] lock_acquire+0xd0/0x218 [ 6022.814896] _raw_spin_lock_irqsave+0x50/0x78 [ 6022.819761] try_to_wake_up+0x54/0x7a0 [ 6022.824018] wake_up_process+0x1c/0x28 [ 6022.828276] wakeup_softirqd+0x38/0x40 [ 6022.832533] __tasklet_schedule_common+0xc4/0xf0 [ 6022.837658] __tasklet_schedule+0x24/0x30 [ 6022.842176] check_irq_resend+0xc8/0x158 [ 6022.846609] irq_startup+0x74/0x128 [ 6022.850606] __enable_irq+0x6c/0x78 [ 6022.854602] enable_irq+0x54/0xa0 [ 6022.858431] its_make_vpe_non_resident+0xa4/0xb8 [ 6022.863557] vgic_v4_put+0x54/0x70 [ 6022.867469] kvm_arch_vcpu_blocking+0x28/0x38 [ 6022.872336] kvm_vcpu_block+0x48/0x490 [ 6022.876594] kvm_handle_wfx+0x18c/0x310 [ 6022.880938] handle_exit+0x138/0x198 [ 6022.885022] kvm_arch_vcpu_ioctl_run+0x4d4/0x978 [ 6022.890148] kvm_vcpu_ioctl+0x3d4/0x8f8 [ 6022.894494] ksys_ioctl+0x90/0xd0 [ 6022.898317] __arm64_sys_ioctl+0x24/0x30 [ 6022.902748] el0_svc_common.constprop.3+0xa8/0x1e8 [ 6022.908046] do_el0_svc+0x28/0x88 [ 6022.911871] el0_svc+0x14/0x40 [ 6022.915434] el0_sync_handler+0x124/0x2b8 [ 6022.919951] el0_sync+0x140/0x180 [ 6022.923773] [ 6022.923773] other info that might help us debug this: [ 6022.923773] [ 6022.931762] Chain exists of: [ 6022.931762] &p->pi_lock --> &rq->lock --> &irq_desc_lock_class [ 6022.931762] [ 6022.942101] Possible unsafe locking scenario: [ 6022.942101] [ 6022.948007] CPU0 CPU1 [ 6022.952523] ---- ---- [ 6022.957039] lock(&irq_desc_lock_class); [ 6022.961036] lock(&rq->lock); [ 6022.966595] lock(&irq_desc_lock_class); [ 6022.973109] lock(&p->pi_lock); [ 6022.976324] [ 6022.976324] *** DEADLOCK *** This is happening because we have a pending doorbell that requires retrigger. As SW retriggering is done in a tasklet, we trigger the circular dependency above. The easy cop-out is to provide a retrigger callback that doesn't require acquiring any extra lock. Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20200310184921.23552-5-maz@kernel.org Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 7809f7011c3bce650e502a98afeb05961470d865 ]

On a very heavily loaded D05 with GICv4, I managed to trigger the
following lockdep splat:

[ 6022.598864] ======================================================
[ 6022.605031] WARNING: possible circular locking dependency detected
[ 6022.611200] 5.6.0-rc4-00026-geee7c7b0f498 #680 Tainted: G            E
[ 6022.618061] ------------------------------------------------------
[ 6022.624227] qemu-system-aar/7569 is trying to acquire lock:
[ 6022.629789] ffff042f97606808 (&p->pi_lock){-.-.}, at: try_to_wake_up+0x54/0x7a0
[ 6022.637102]
[ 6022.637102] but task is already holding lock:
[ 6022.642921] ffff002fae424cf0 (&irq_desc_lock_class){-.-.}, at: __irq_get_desc_lock+0x5c/0x98
[ 6022.651350]
[ 6022.651350] which lock already depends on the new lock.
[ 6022.651350]
[ 6022.659512]
[ 6022.659512] the existing dependency chain (in reverse order) is:
[ 6022.666980]
[ 6022.666980] -> #2 (&irq_desc_lock_class){-.-.}:
[ 6022.672983]        _raw_spin_lock_irqsave+0x50/0x78
[ 6022.677848]        __irq_get_desc_lock+0x5c/0x98
[ 6022.682453]        irq_set_vcpu_affinity+0x40/0xc0
[ 6022.687236]        its_make_vpe_non_resident+0x6c/0xb8
[ 6022.692364]        vgic_v4_put+0x54/0x70
[ 6022.696273]        vgic_v3_put+0x20/0xd8
[ 6022.700183]        kvm_vgic_put+0x30/0x48
[ 6022.704182]        kvm_arch_vcpu_put+0x34/0x50
[ 6022.708614]        kvm_sched_out+0x34/0x50
[ 6022.712700]        __schedule+0x4bc/0x7f8
[ 6022.716697]        schedule+0x50/0xd8
[ 6022.720347]        kvm_arch_vcpu_ioctl_run+0x5f0/0x978
[ 6022.725473]        kvm_vcpu_ioctl+0x3d4/0x8f8
[ 6022.729820]        ksys_ioctl+0x90/0xd0
[ 6022.733642]        __arm64_sys_ioctl+0x24/0x30
[ 6022.738074]        el0_svc_common.constprop.3+0xa8/0x1e8
[ 6022.743373]        do_el0_svc+0x28/0x88
[ 6022.747198]        el0_svc+0x14/0x40
[ 6022.750761]        el0_sync_handler+0x124/0x2b8
[ 6022.755278]        el0_sync+0x140/0x180
[ 6022.759100]
[ 6022.759100] -> #1 (&rq->lock){-.-.}:
[ 6022.764143]        _raw_spin_lock+0x38/0x50
[ 6022.768314]        task_fork_fair+0x40/0x128
[ 6022.772572]        sched_fork+0xe0/0x210
[ 6022.776484]        copy_process+0x8c4/0x18d8
[ 6022.780742]        _do_fork+0x88/0x6d8
[ 6022.784478]        kernel_thread+0x64/0x88
[ 6022.788563]        rest_init+0x30/0x270
[ 6022.792390]        arch_call_rest_init+0x14/0x1c
[ 6022.796995]        start_kernel+0x498/0x4c4
[ 6022.801164]
[ 6022.801164] -> #0 (&p->pi_lock){-.-.}:
[ 6022.806382]        __lock_acquire+0xdd8/0x15c8
[ 6022.810813]        lock_acquire+0xd0/0x218
[ 6022.814896]        _raw_spin_lock_irqsave+0x50/0x78
[ 6022.819761]        try_to_wake_up+0x54/0x7a0
[ 6022.824018]        wake_up_process+0x1c/0x28
[ 6022.828276]        wakeup_softirqd+0x38/0x40
[ 6022.832533]        __tasklet_schedule_common+0xc4/0xf0
[ 6022.837658]        __tasklet_schedule+0x24/0x30
[ 6022.842176]        check_irq_resend+0xc8/0x158
[ 6022.846609]        irq_startup+0x74/0x128
[ 6022.850606]        __enable_irq+0x6c/0x78
[ 6022.854602]        enable_irq+0x54/0xa0
[ 6022.858431]        its_make_vpe_non_resident+0xa4/0xb8
[ 6022.863557]        vgic_v4_put+0x54/0x70
[ 6022.867469]        kvm_arch_vcpu_blocking+0x28/0x38
[ 6022.872336]        kvm_vcpu_block+0x48/0x490
[ 6022.876594]        kvm_handle_wfx+0x18c/0x310
[ 6022.880938]        handle_exit+0x138/0x198
[ 6022.885022]        kvm_arch_vcpu_ioctl_run+0x4d4/0x978
[ 6022.890148]        kvm_vcpu_ioctl+0x3d4/0x8f8
[ 6022.894494]        ksys_ioctl+0x90/0xd0
[ 6022.898317]        __arm64_sys_ioctl+0x24/0x30
[ 6022.902748]        el0_svc_common.constprop.3+0xa8/0x1e8
[ 6022.908046]        do_el0_svc+0x28/0x88
[ 6022.911871]        el0_svc+0x14/0x40
[ 6022.915434]        el0_sync_handler+0x124/0x2b8
[ 6022.919951]        el0_sync+0x140/0x180
[ 6022.923773]
[ 6022.923773] other info that might help us debug this:
[ 6022.923773]
[ 6022.931762] Chain exists of:
[ 6022.931762]   &p->pi_lock --> &rq->lock --> &irq_desc_lock_class
[ 6022.931762]
[ 6022.942101]  Possible unsafe locking scenario:
[ 6022.942101]
[ 6022.948007]        CPU0                    CPU1
[ 6022.952523]        ----                    ----
[ 6022.957039]   lock(&irq_desc_lock_class);
[ 6022.961036]                                lock(&rq->lock);
[ 6022.966595]                                lock(&irq_desc_lock_class);
[ 6022.973109]   lock(&p->pi_lock);
[ 6022.976324]
[ 6022.976324]  *** DEADLOCK ***

This is happening because we have a pending doorbell that requires
retrigger. As SW retriggering is done in a tasklet, we trigger the
circular dependency above.

The easy cop-out is to provide a retrigger callback that doesn't
require acquiring any extra lock.

Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20200310184921.23552-5-maz@kernel.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
irqchip/versatile-fpga: Handle chained IRQs properly 2020-04-17T08:50:02+00:00 Sungbo Eo mans0n@gorani.run 2020-03-19T02:34:48+00:00 3f755f5233a2a046842f22bcce167dfea4ce1909 [ Upstream commit 486562da598c59e9f835b551d7cf19507de2d681 ] Enclose the chained handler with chained_irq_{enter,exit}(), so that the muxed interrupts get properly acked. This patch also fixes a reboot bug on OX820 SoC, where the jiffies timer interrupt is never acked. The kernel waits a clock tick forever in calibrate_delay_converge(), which leads to a boot hang. Fixes: c41b16f8c9d9 ("ARM: integrator/versatile: consolidate FPGA IRQ handling code") Signed-off-by: Sungbo Eo <mans0n@gorani.run> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20200319023448.1479701-1-mans0n@gorani.run Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 486562da598c59e9f835b551d7cf19507de2d681 ]

Enclose the chained handler with chained_irq_{enter,exit}(), so that the
muxed interrupts get properly acked.

This patch also fixes a reboot bug on OX820 SoC, where the jiffies timer
interrupt is never acked. The kernel waits a clock tick forever in
calibrate_delay_converge(), which leads to a boot hang.

Fixes: c41b16f8c9d9 ("ARM: integrator/versatile: consolidate FPGA IRQ handling code")
Signed-off-by: Sungbo Eo <mans0n@gorani.run>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20200319023448.1479701-1-mans0n@gorani.run
Signed-off-by: Sasha Levin <sashal@kernel.org>