From: Paolo Bonzini <pbonzini@redhat.com>
To: Peter Maydell <peter.maydell@linaro.org>,
QEMU Developers <qemu-devel@nongnu.org>
Subject: Re: [Qemu-devel] rcu kicking CPU threads before they're set up...
Date: Wed, 11 Mar 2015 15:06:44 +0100 [thread overview]
Message-ID: <55004BF4.7090608@redhat.com> (raw)
In-Reply-To: <CAFEAcA88pnEAye8yMOk0E5du_2xwidibO8ynF=QH3dmTkYyw+w@mail.gmail.com>
On 11/03/2015 11:23, Peter Maydell wrote:
> I noticed this while I was trying to debug something and so was
> single stepping through the CPU realize function.
>
> The rcu thread seems to get set up and try to start working too
> early in QEMU's initialization process. Specifically, it can try
> to do things before we've completed the creation and init of all
> the CPUs: I'm seeing call_rcu_thread() calling qemu_mutex_lock_iothread()
> calling qemu_cpu_kick_thread() before we've even finished actually
> creating and realizing the CPU objects. This segfaults because
> cpu->thread isn't set yet.
Should be fixed by now:
commit 6b49809c597331803ea941eadda813e5bb4e8fe2
Author: Paolo Bonzini <pbonzini@redhat.com>
Date: Fri Feb 27 19:58:23 2015 +0100
cpus: fix deadlock and segfault in qemu_mutex_lock_iothread
commit 21618b3e55ad2c6fede0bffcaea466091811ce59
Author: Paolo Bonzini <pbonzini@redhat.com>
Date: Fri Feb 27 20:01:03 2015 +0100
cpus: be more paranoid in avoiding deadlocks
Paolo
prev parent reply other threads:[~2015-03-11 14:07 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-03-11 10:23 [Qemu-devel] rcu kicking CPU threads before they're set up Peter Maydell
2015-03-11 14:06 ` Paolo Bonzini [this message]
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