Re: [PATCH] arm64: kprobes: Restore local irqflag if kprobes is cancelled

From: Will Deacon
Date: Tue Apr 13 2021 - 13:49:34 EST


On Mon, 12 Apr 2021 17:41:01 +0800, Jisheng Zhang wrote:
> If instruction being single stepped caused a page fault, the kprobes
> is cancelled to let the page fault handler continue as a normal page
> fault. But the local irqflags are disabled so cpu will restore pstate
> with DAIF masked. After pagefault is serviced, the kprobes is
> triggerred again, we overwrite the saved_irqflag by calling
> kprobes_save_local_irqflag(). NOTE, DAIF is masked in this new saved
> irqflag. After kprobes is serviced, the cpu pstate is retored with
> DAIF masked.
>
> [...]

Applied to arm64 (for-next/fixes), thanks!

[1/1] arm64: kprobes: Restore local irqflag if kprobes is cancelled
https://git.kernel.org/arm64/c/738fa58ee132

Cheers,
--
Will

https://fixes.arm64.dev
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