27.04.2020 17:45, Dmitry Osipenko пишет: > 27.04.2020 17:13, Dmitry Osipenko пишет: >> 27.04.2020 15:46, Dmitry Osipenko пишет: >>> 23.04.2020 13:56, Jon Hunter пишет: >>>>>> So I think that part of the problem already existed prior to these >>>>>> patches. Without your patches I see ... >>>>>> >>>>>> [ 59.543528] tegra-i2c 7000d000.i2c: i2c transfer timed out >>>>>> [ 59.549036] vdd_sata,avdd_plle: failed to disable >>>>>> [ 59.553778] Failed to disable avdd-plle: -110 >>>>>> [ 59.558150] tegra-pcie 3000.pcie: failed to disable regulators: -110 >>>>> Does this I2C timeout happen with my patches? Could you please post full >>>>> logs of an older and the recent kernel versions? >>>> I believe that it does, but I need to check. >>>> >>> >>> Jon, could you please confirm that you're seeing those regulator-disable >>> errors with my patch? I don't see those errors in yours original log [1]. >>> >>> [1] >>> https://lore.kernel.org/lkml/1e259e22-c300-663a-e537-18d854e0f478@xxxxxxxxxx/ >>> >>> Again, could you please post the *full* logs? >>> >>> If regulator's disabling was "failing" before without my patch because >>> of the I2C interrupt being force-disabled during of NOIRQ phase, and now >>> regulator's disabling succeeds with my patch because IRQ is manually >>> handled after the timeout, then this could be bad. It means that >>> regulator was actually getting disabled, but I2C driver was timing out >>> because interrupt couldn't be handled in NOIRQ phase, which should >>> result in a dead PCIe on a resume from suspend since regulator's core >>> thinks that regulator is enabled (I2C said it failed to disable), while >>> it is actually disabled. >>> >>> Do you have anything plugged into the PCIe slot in yours testing farm? >>> It wouldn't surprise me if the plugged card isn't functional after >>> resume from suspend on a stable kernels. >>> >> >> I actually now see that interrupt is not allowed to be enabled during >> the NOIRQ phase: >> >> https://elixir.bootlin.com/linux/v5.7-rc3/source/kernel/irq/manage.c#L640 >> >> it should be worthwhile to turn it into a WARN_ON. >> > > Oh, wait! There is already a warning there.. hmm. > Aha, the disable depth for the I2C interrupt is 2 after suspend_device_irq(), that's why there is no warning. This should catch the bug and trigger the warning: --- >8 --- diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c index 453a8a0f4804..fe25104d8b22 100644 --- a/kernel/irq/manage.c +++ b/kernel/irq/manage.c @@ -653,6 +653,8 @@ void __enable_irq(struct irq_desc *desc) break; } default: + if (desc->istate & IRQS_SUSPENDED) + goto err_out; desc->depth--; } } --- >8 --- Jon could you please give it a try? Will this change produce a warning for the I2C driver on a PCIe suspend for the v5.6 kernel?
