linux-kernel - Re: [PATCH RFC 01/14] x86/asm: add iosubmit_cmds512() based on movdir64b CPU instruction

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: <20191120232645.GO2634@zn.tnic>
Date:   Thu, 21 Nov 2019 00:26:45 +0100
From:   Borislav Petkov <bp@...en8.de>
To:     "Luck, Tony" <tony.luck@...el.com>
Cc:     Dave Jiang <dave.jiang@...el.com>, dmaengine@...r.kernel.org,
        linux-kernel@...r.kernel.org, vkoul@...nel.org,
        dan.j.williams@...el.com, jing.lin@...el.com, ashok.raj@...el.com,
        sanjay.k.kumar@...el.com, megha.dey@...el.com,
        jacob.jun.pan@...el.com, yi.l.liu@...el.com, axboe@...nel.dk,
        akpm@...ux-foundation.org, tglx@...utronix.de, mingo@...hat.com,
        fenghua.yu@...el.com, hpa@...or.com
Subject: Re: [PATCH RFC 01/14] x86/asm: add iosubmit_cmds512() based on
 movdir64b CPU instruction

On Wed, Nov 20, 2019 at 03:19:23PM -0800, Luck, Tony wrote:
> That's the underlying functionality of the MOVDIR64B instruction. A
> posted write so no way to know if it succeeded.

So how do you know whether any of the writes went through?

> When using dedicated queues the caller must keep count of how many
> operations are in flight and not send more than the depth of the
> queue.

This way?

-- 
Regards/Gruss,
    Boris.

https://people.kernel.org/tglx/notes-about-netiquette