Date: Mon, 19 Dec 2016 15:24:05 +0100
From: Radim =?utf-8?B?S3LEjW3DocWZ?= <rkrcmar@redhat.com>
To: David Matlack <dmatlack@google.com>
Cc: kvm@vger.kernel.org, linux-kernel@vger.kernel.org, pbonzini@redhat.com,
        peterz@infradead.org, haokexin@gmail.com, mpe@ellerman.id.au,
        yongjun_wei@trendmicro.com.cn, rusty@rustcorp.com.au,
        jbaron@akamai.com
Subject: Re: [PATCH 2/2] KVM: x86: flush pending lapic jump label updates on
 module unload
Message-ID: <20161219142404.GA21302@potion>
References: <1481927436-104568-1-git-send-email-dmatlack@google.com>
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2016-12-16 14:30-0800, David Matlack:
> KVM's lapic emulation uses static_key_deferred (apic_{hw,sw}_disabled).
> These are implemented with delayed_work structs which can still be
> pending when the KVM module is unloaded. We've seen this cause kernel
> panics when the kvm_intel module is quickly reloaded.
> 
> Use the new static_key_deferred_flush() API to flush pending updates on
> module unload.
> 
> Signed-off-by: David Matlack <dmatlack@google.com>
> ---

Oh, this forgotten bug.  I guess that patches to do this automatically
from generic module unload code would be over-engineering it ...

Reviewed-by: Radim Krčmář <rkrcmar@redhat.com>

Thanks.