linux-kernel - Re: [PATCH v2 5/8] docs: sysfs-block: document stable

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: <b8422f2f-b9cb-7914-b94a-559de8315371@acm.org>
Date:   Wed, 8 Dec 2021 14:59:03 -0800
From:   Bart Van Assche <bvanassche@....org>
To:     Eric Biggers <ebiggers@...nel.org>
Cc:     linux-block@...r.kernel.org, Jens Axboe <axboe@...nel.dk>,
        linux-doc@...r.kernel.org,
        Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        linux-kernel@...r.kernel.org, Hannes Reinecke <hare@...e.de>
Subject: Re: [PATCH v2 5/8] docs: sysfs-block: document stable_writes

On 12/8/21 2:34 PM, Eric Biggers wrote:
> Yes, I meant "written out to disk" in the general sense of writeback, not in the
> sense of when the data reaches its final destination.  I'm not sure what the
> best way to explain it is.  I think it's more than just "the process of
> transferring data from host memory to the device", as that is just part of a
> write request, whereas stable_writes applies to whole requests.  How about:
> 
> 		[RW] This file will contain '1' if memory must not be modified
> 		while it is being used in a write request to this device.  When
> 		this is the case and the kernel is performing writeback of a
> 		page, the kernel will wait for writeback to complete before
> 		allowing the page to be modified again, rather than allowing
> 		immediate modification as is normally the case.  This
> 		restriction arises when the device accesses the memory multiple
> 		times where the same data must be seen every time -- for
> 		example, once to calculate a checksum and once to actually write
> 		the data.  If no such restriction exists, this file will contain
> 		'0'.  This file is writable for testing purposes.

The above sounds good to me.

Thanks,

Bart.