linux-kernel - Re: [PATCH 05/10] staging: erofs: add a full barrier in erofs_workgroup

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: <1d1fd688-0cb5-cbac-9213-f56f7e356bca@huawei.com>
Date:   Thu, 22 Nov 2018 18:56:32 +0800
From:   Gao Xiang <gaoxiang25@...wei.com>
To:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>
CC:     <devel@...verdev.osuosl.org>, <linux-erofs@...ts.ozlabs.org>,
        Chao Yu <yuchao0@...wei.com>,
        LKML <linux-kernel@...r.kernel.org>, <weidu.du@...wei.com>,
        Miao Xie <miaoxie@...wei.com>
Subject: Re: [PATCH 05/10] staging: erofs: add a full barrier in
 erofs_workgroup_unfreeze

Hi Greg,

On 2018/11/22 18:22, Greg Kroah-Hartman wrote:
> Please document this memory barrier.  It does not make much sense to
> me...

Because we need to make the other observers noticing the latest values modified
in this locking period before unfreezing the whole workgroup, one way is to use
a memory barrier and the other way is to use ACQUIRE and RELEASE. we selected
the first one.

Hmmm...ok, I will add a simple message to explain this, but I think that is
plain enough for a lock...

Thanks,
Gao Xiang

> 
> thanks,
> 
> greg k-h