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From: "Jason A. Donenfeld" <Jason@zx2c4.com>
Date: Thu, 10 Nov 2016 18:39:54 +0100
Message-ID: <CAHmME9rv8CfgY87S_HVN3njc2RnisjoxzfZxY=H=2FzZkrQqLg@mail.gmail.com>
Subject: Re: Proposal: HAVE_SEPARATE_IRQ_STACK?
To: Thomas Gleixner <tglx@linutronix.de>
Cc: LKML <linux-kernel@vger.kernel.org>, linux-mips@linux-mips.org,
        linux-mm@kvack.org, WireGuard mailing list <wireguard@lists.zx2c4.com>,
        k@vodka.home.kg
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Hi Thomas,

On Thu, Nov 10, 2016 at 2:00 PM, Thomas Gleixner <tglx@linutronix.de> wrote:
> Do not even think about going there. That's going to be a major
> mess.

Lol! Okay. Thank you for reigning in my clearly reckless
propensities... Sometimes playing in traffic is awfully tempting.

>
> As a short time workaround you can increase THREAD_SIZE_ORDER for now and
> then fix it proper with switching to seperate irq stacks.

Okay. I think in the end I'll kmalloc, accept the 16% slowdown [1],
and focus efforts on having a separate IRQ stack. Matt emailed in this
thread saying he was already looking into it, so I think by the time
that slowdown makes a difference, we'll have the right pieces in place
anyway.

Thanks for the guidance here.

Regards,
Jason

[1] https://git.zx2c4.com/WireGuard/commit/?id=cc3d7df096a88cdf96d016bdcb2f78fa03abb6f3