linux-kernel - Re: [PATCH 01/12] arm64: hibernate.c: create a new function to handle cpu_up(sleep

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20191119225100.gqiiiwoyt3yntdoj@e107158-lin.cambridge.arm.com>
Date:   Tue, 19 Nov 2019 22:51:00 +0000
From:   Qais Yousef <qais.yousef@....com>
To:     Thomas Gleixner <tglx@...utronix.de>
Cc:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        Catalin Marinas <catalin.marinas@....com>,
        Will Deacon <will@...nel.org>,
        Steve Capper <steve.capper@....com>,
        Richard Fontana <rfontana@...hat.com>,
        James Morse <james.morse@....com>,
        Mark Rutland <mark.rutland@....com>,
        Josh Poimboeuf <jpoimboe@...hat.com>,
        Ingo Molnar <mingo@...nel.org>,
        "Peter Zijlstra (Intel)" <peterz@...radead.org>,
        Nicholas Piggin <npiggin@...il.com>,
        Daniel Lezcano <daniel.lezcano@...aro.org>,
        Jiri Kosina <jkosina@...e.cz>,
        Pavankumar Kondeti <pkondeti@...eaurora.org>,
        Zhenzhong Duan <zhenzhong.duan@...cle.com>,
        linux-arm-kernel@...ts.infradead.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH 01/12] arm64: hibernate.c: create a new function to
 handle cpu_up(sleep_cpu)

On 11/19/19 23:31, Thomas Gleixner wrote:
> On Wed, 30 Oct 2019, Qais Yousef wrote:
> >  
> > +int hibernation_bringup_sleep_cpu(unsigned int sleep_cpu)
> 
> That function name is horrible. Aside of that I really have to ask how you
> end up hibernating on an offline CPU?

James Morse can probably explain better.

But AFAIU we could sleep on any CPU, but on the next cold boot that CPU could
become offline as a side effect of using maxcpus= for example.

How about bringup_hibernate_cpu() as a name? I could add the above as an
explanation of why we need this call too.

It does seem to me that this is a generic problem that we might be able to
handle generically, but I'm not sure how.

Thanks

--
Qais Yousef