linux-kernel - Re: [PATCH v3] fs: Invalidate the cache for a parent block-device if fsync() is called for a partition

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: <20120126214534.GA9319@infradead.org>
Date:	Thu, 26 Jan 2012 16:45:34 -0500
From:	Christoph Hellwig <hch@...radead.org>
To:	Andrew Morton <akpm@...ux-foundation.org>
Cc:	Niels de Vos <ndevos@...hat.com>, linux-fsdevel@...r.kernel.org,
	linux-kernel@...r.kernel.org, Al Viro <viro@...iv.linux.org.uk>,
	Mikulas Patocka <mpatocka@...hat.com>,
	Jeff Moyer <jmoyer@...hat.com>,
	"Bryn M. Reeves" <bmr@...hat.com>
Subject: Re: [PATCH v3] fs: Invalidate the cache for a parent block-device if
 fsync() is called for a partition

On Thu, Jan 26, 2012 at 01:40:51PM -0800, Andrew Morton wrote:
> The Right Thing To Do here is to make the kernel behave logically and
> predictably, then modify the userspace tools.  But if we're modifying
> the userspace tools then we would just change userspace to issue a
> BLKFLSBUF to /dev/sda and leave the kernel alone.

The right fix is to make partition and whole disk access coherent,
which is fairly simply:

 - create the block device inode/mapping per gendisk, and only reference
   count it per block_device
 - make sure blkdev_get_block(s) applies the correct offset if used on
   partitions

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/