linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Qais Yousef <qais.yousef@arm.com>
To: Michael Ellerman <mpe@ellerman.id.au>
Cc: Thomas Gleixner <tglx@linutronix.de>,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	Benjamin Herrenschmidt <benh@kernel.crashing.org>,
	Paul Mackerras <paulus@samba.org>,
	Enrico Weigelt <info@metux.net>, Ram Pai <linuxram@us.ibm.com>,
	Nicholas Piggin <npiggin@gmail.com>,
	Thiago Jung Bauermann <bauerman@linux.ibm.com>,
	Christophe Leroy <christophe.leroy@c-s.fr>,
	linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 03/12] powerpc: Replace cpu_up/down with device_online/offline
Date: Tue, 19 Nov 2019 09:47:47 +0000	[thread overview]
Message-ID: <20191119094747.4asxwnmyrjy5d5io@e107158-lin.cambridge.arm.com> (raw)
In-Reply-To: <87h830d5n8.fsf@mpe.ellerman.id.au>

On 11/19/19 12:19, Michael Ellerman wrote:
> Qais Yousef <qais.yousef@arm.com> writes:
> > The core device API performs extra housekeeping bits that are missing
> > from directly calling cpu_up/down.
> >
> > See commit a6717c01ddc2 ("powerpc/rtas: use device model APIs and
> > serialization during LPM") for an example description of what might go
> > wrong.
> >
> > This also prepares to make cpu_up/down a private interface for anything
> > but the cpu subsystem.
> >
> > Signed-off-by: Qais Yousef <qais.yousef@arm.com>
> > CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
> > CC: Paul Mackerras <paulus@samba.org>
> > CC: Michael Ellerman <mpe@ellerman.id.au>
> > CC: Enrico Weigelt <info@metux.net>
> > CC: Ram Pai <linuxram@us.ibm.com>
> > CC: Nicholas Piggin <npiggin@gmail.com>
> > CC: Thiago Jung Bauermann <bauerman@linux.ibm.com>
> > CC: Christophe Leroy <christophe.leroy@c-s.fr>
> > CC: Thomas Gleixner <tglx@linutronix.de>
> > CC: linuxppc-dev@lists.ozlabs.org
> > CC: linux-kernel@vger.kernel.org
> > ---
> >  arch/powerpc/kernel/machine_kexec_64.c | 4 +++-
> >  1 file changed, 3 insertions(+), 1 deletion(-)
> 
> My initial though is "what about kdump", but that function is not called
> during kdump, so there should be no issue with the extra locking leading
> to deadlocks in a crash.
> 
> Acked-by: Michael Ellerman <mpe@ellerman.id.au>

Thanks.

> 
> I assume you haven't actually tested it?

Only compile tested it I'm afraid. Would appreciate if you can give it a spin.
Otherwise I'd be happy to try it out on qemu.

Cheers

--
Qais Yousef

  reply	other threads:[~2019-11-19  9:47 UTC|newest]

Thread overview: 33+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <20191030153837.18107-1-qais.yousef@arm.com>
2019-10-30 15:38 ` [PATCH 01/12] arm64: hibernate.c: create a new function to handle cpu_up(sleep_cpu) Qais Yousef
2019-11-19 22:31   ` Thomas Gleixner
2019-11-19 22:51     ` Qais Yousef
2019-11-19 23:01       ` Thomas Gleixner
2019-11-19 23:21         ` Qais Yousef
2019-10-30 15:38 ` [PATCH 02/12] x86: Replace cpu_up/down with devcie_online/offline Qais Yousef
2019-10-30 15:38 ` [PATCH 03/12] powerpc: Replace cpu_up/down with device_online/offline Qais Yousef
2019-11-19  1:19   ` Michael Ellerman
2019-11-19  9:47     ` Qais Yousef [this message]
2019-10-30 15:38 ` [PATCH 04/12] ia64: Replace cpu_down with freeze_secondary_cpus Qais Yousef
2019-11-02  4:59   ` kbuild test robot
2019-11-19 22:21   ` Thomas Gleixner
2019-11-19 22:32     ` Qais Yousef
2019-11-19 22:59       ` Thomas Gleixner
2019-11-19 23:19         ` Qais Yousef
2019-11-20  8:46           ` Thomas Gleixner
2019-11-20 10:49             ` Qais Yousef
2019-10-30 15:38 ` [PATCH 05/12] sparc: Replace cpu_up/down with device_online/offline Qais Yousef
2019-10-30 19:33   ` David Miller
2019-10-30 15:38 ` [PATCH 06/12] parisc: " Qais Yousef
2019-11-20 11:09   ` Qais Yousef
2019-11-22 19:51     ` Helge Deller
2019-11-24 10:20       ` Qais Yousef
2019-10-30 15:38 ` [PATCH 07/12] driver: base: cpu: export device_online/offline Qais Yousef
2019-11-02 17:17   ` Greg Kroah-Hartman
2019-10-30 15:38 ` [PATCH 08/12] driver: xen: Replace cpu_up/down with device_online/offline Qais Yousef
2019-10-30 15:38 ` [PATCH 09/12] firmware: psci: " Qais Yousef
2019-10-30 15:38 ` [PATCH 10/12] torture: " Qais Yousef
2019-10-30 15:38 ` [PATCH 11/12] smp: Create a new function to bringup nonboot cpus online Qais Yousef
2019-11-19 22:42   ` Thomas Gleixner
2019-10-30 15:38 ` [PATCH 12/12] cpu: Hide cpu_up/down Qais Yousef
2019-11-19 22:25   ` Thomas Gleixner
2019-11-19 22:36     ` Qais Yousef

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20191119094747.4asxwnmyrjy5d5io@e107158-lin.cambridge.arm.com \
    --to=qais.yousef@arm.com \
    --cc=bauerman@linux.ibm.com \
    --cc=benh@kernel.crashing.org \
    --cc=christophe.leroy@c-s.fr \
    --cc=gregkh@linuxfoundation.org \
    --cc=info@metux.net \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linuxppc-dev@lists.ozlabs.org \
    --cc=linuxram@us.ibm.com \
    --cc=mpe@ellerman.id.au \
    --cc=npiggin@gmail.com \
    --cc=paulus@samba.org \
    --cc=tglx@linutronix.de \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).