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From:   D Scott Phillips <scott@os.amperecomputing.com>
To:     linux-arm-kernel@lists.infradead.org,
        James Morse <james.morse@arm.com>
Cc:     Catalin Marinas <catalin.marinas@arm.com>,
        Will Deacon <will@kernel.org>, linux-kernel@vger.kernel.org,
        Darren Hart <darren@os.amperecomputing.com>,
        Mihai Carabas <mihai.carabas@oracle.com>
Subject: Re: [PATCH v6] arm64: sdei: abort running SDEI handlers during crash
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Date:   Mon, 24 Jul 2023 13:31:51 -0700
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D Scott Phillips <scott@os.amperecomputing.com> writes:

> Interrupts are blocked in SDEI context, per the SDEI spec: "The client
> interrupts cannot preempt the event handler." If we crashed in the SDEI
> handler-running context (as with ACPI's AGDI) then we need to clean up the
> SDEI state before proceeding to the crash kernel so that the crash kernel
> can have working interrupts.
>
> Track the active SDEI handler per-cpu so that we can COMPLETE_AND_RESUME
> the handler, discarding the interrupted context.
>
> Fixes: f5df26961853 ("arm64: kernel: Add arch-specific SDEI entry code and CPU masking")
> Signed-off-by: D Scott Phillips <scott@os.amperecomputing.com>
> Cc: stable@vger.kernel.org

Hi James, ping on this