From: Kees Cook <keescook@chromium.org>
To: Paramjit Oberoi <pso@chromium.org>
Cc: LKML <linux-kernel@vger.kernel.org>,
Linux-Fsdevel <linux-fsdevel@vger.kernel.org>,
Dmitry Torokhov <dtor@chromium.org>,
Anton Vorontsov <anton@enomsg.org>,
Colin Cross <ccross@android.com>, Tony Luck <tony.luck@intel.com>
Subject: Re: [PATCH 1/1] pstore/ram: Ensure stable pmsg address with per-CPU ftrace buffers
Date: Tue, 11 Oct 2022 15:22:32 -0700 [thread overview]
Message-ID: <202210111521.B8D8156490@keescook> (raw)
In-Reply-To: <CAHqLn7EG=iKmu1tMJ_Um4MmpLVztshfzACnrzcZqPvvcRRCKuQ@mail.gmail.com>
On Tue, Oct 11, 2022 at 01:44:54PM -0700, Paramjit Oberoi wrote:
> > > The only downside is it would break some code that works today because
> it
> > > ran in contexts where the pmsg address was stable (no per-cpu ftrace
> > > buffers, or power-of-two CPUs).
> >
> > I don't follow? And actually, I wonder about the original patch now --
> > nothing should care about the actual addresses. Everything should be
> > coming out of the pstore filesystem.
>
> We are running VMs with the pstore RAM mapped to a file, and using some
> tools outside the VM to read/manipulate the pstore after VM shutdown.
Ah-ha! Interesting. Well, I think it will be more stable this way even
for that. :)
--
Kees Cook
prev parent reply other threads:[~2022-10-11 22:22 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-10-11 18:36 [PATCH 0/1] pstore/ram: Ensure stable pmsg address with per-CPU ftrace buffers pso
2022-10-11 18:36 ` [PATCH 1/1] " pso
2022-10-11 19:38 ` Kees Cook
[not found] ` <CAHqLn7Hd6KaNYA=goS7=dumrG3wZedbV1+ANa+-dZzFPiP_vsQ@mail.gmail.com>
2022-10-11 20:04 ` Kees Cook
[not found] ` <CAHqLn7EG=iKmu1tMJ_Um4MmpLVztshfzACnrzcZqPvvcRRCKuQ@mail.gmail.com>
2022-10-11 22:22 ` Kees Cook [this message]
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