Re: [PATCH 20/62] sparc: irq: Remove IRQF_DISABLED

From: David Miller
Date: Wed Sep 07 2011 - 14:15:45 EST


From: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Date: Wed, 7 Sep 2011 19:57:21 +0200 (CEST)

> On Wed, 7 Sep 2011, David Miller wrote:
>> From: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
>> Date: Wed, 7 Sep 2011 19:33:52 +0200 (CEST)
>>
>> We had big problems when openning thousands of virtual network
>> devices, each with their own unique IRQ, and pointed all at the same
>> cpu, and we'd get IRQ stack overflows.
>>
>> See commit c58543c869606532c2382f027d6466f4672ea756
>>
>> So this change to make IRQF_DISABLED a nop has reintroduced this bug.
>
> See commit e58aa3d2d0cc01ad8d6f7f640a0670433f794922
>
> We run ALL interrupt handlers with interrupts disabled for that reason
> and we even check and yell when an interrupt handler returns with
> interrupts enabled. That's why IRQF_DISABLED became meaningless.

Awesome.

Can I politely ask that a reference to that commit and something like
your paragraph here explaining things is added to these IRQF_DISABLED
removal patches?

Thanks!
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