[PATCH 7/8 v1.5] arm64: Always keep DAIF.[IF] in sync

Hector Martin marcan at marcan.st
Mon Feb 22 12:39:11 EST 2021

On 20/02/2021 03.26, Mark Rutland wrote:
> On Sat, Feb 20, 2021 at 02:25:30AM +0900, Hector Martin wrote:
>> Apple SoCs (A11 and newer) have some interrupt sources hardwired to the
>> FIQ line. We implement support for this by simply treating IRQs and FIQs
>> the same way in the interrupt vectors.
>> To support these systems, the FIQ mask bit needs to be kept in sync with
>> the IRQ mask bit, so both kinds of exceptions are masked together. No
>> other platforms should be delivering FIQ exceptions right now, and we
>> already unmask FIQ in normal process context, so this should not have an
>> effect on other systems - if spurious FIQs were arriving, they would
>> already panic the kernel.
> This looks good to me; I've picked this up and pushed out my arm64/fiq
> branch [1,2] incorporating this, tagged as arm64-fiq-20210219.
> I'll give this version a few days to gather comments before I post a v2.
> [1] git://git.kernel.org/pub/scm/linux/kernel/git/mark/linux.git arm64/fiq
> [2] https://git.kernel.org/pub/scm/linux/kernel/git/mark/linux.git/log/?h=arm64/fiqA

Thanks! Any chance you can do a rebase on top of torvalds/master? Since 
Marc's nVHE changes went in, we're going to need to add a workaround 
patch for the M1's lack of nVHE mode, which is going to be in the next 
version of my M1 bringup series - but right now that would involve 
telling people to merge two trees to build a base to apply it on, which 
is sub-optimal.

Hector Martin (marcan at marcan.st)
Public Key: https://mrcn.st/pub

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