linux-kernel - Re: [PATCH] crypto: lib/chacha20poly1305 - Set SG_MITER

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: Windows password security audit tool. GUI, reports in PDF.

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

Message-ID: <20200915100506.GA27268@gondor.apana.org.au>
Date:   Tue, 15 Sep 2020 20:05:06 +1000
From:   Herbert Xu <herbert@...dor.apana.org.au>
To:     Ard Biesheuvel <ardb@...nel.org>
Cc:     Thomas Gleixner <tglx@...utronix.de>,
        Linus Torvalds <torvalds@...ux-foundation.org>,
        LKML <linux-kernel@...r.kernel.org>,
        Linux Crypto Mailing List <linux-crypto@...r.kernel.org>
Subject: Re: [PATCH] crypto: lib/chacha20poly1305 - Set SG_MITER_ATOMIC
 unconditionally

On Tue, Sep 15, 2020 at 01:02:10PM +0300, Ard Biesheuvel wrote:
>
> > I'd rather go for a preemptible/sleepable version of highmem mapping
> > which is in itself consistent for both highmen and not highmem.
> 
> I don't think we need to obsess about highmem, although we should
> obviously take care not to regress its performance unnecessarily. What
> I want to avoid is to burden a brand new subsystem with legacy highmem
> baggage simply because we could not agree on how to avoid that.

I think what Thomas is proposing should address your concerns Ard.
As long as nobody objects to the slight performance degradation on
legacy highmem platforms it should make kmap_atomic just go away on
modern platforms.

Cheers,
-- 
Email: Herbert Xu <herbert@...dor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt