linux-kernel - Re: [PATCH] ubifs: Add freeze support

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]

Date:   Fri, 26 May 2017 11:52:42 +0200
From:   Richard Weinberger <richard@....at>
To:     Hyunchul Lee <hyc.lee@...il.com>
Cc:     Artem Bityutskiy <dedekind1@...il.com>, adrian.hunter@...el.com,
        linux-kernel@...r.kernel.org, linux-fsdevel@...r.kernel.org,
        linux-mtd@...ts.infradead.org, kernel-team@....com
Subject: Re: [PATCH] ubifs: Add freeze support

Hyunchul,

Am 26.05.2017 um 01:30 schrieb Hyunchul Lee:
> From: Hyunchul Lee <cheol.lee@....com>
> 
> for un/freeze support, implement freeze_super and un/freeze_fs
> of super_operations.
> ubifs_freeze_super just calls freeze_super. because freeze_super always
> succeeds if file system is read-only,  UBIFS errors should be checked.
> if there are errors, UBIFS is switched to read-only mode.
> ubifs_freeze_fs runs commit if TNC/LPT isn't clean. though all writes
> are blocked and sync_fs is called before, if commit alreay was started
> before writes are blocked, TNC/LPT might have dirty COW nodes.

you explain how you implement that feature, but not why.
What is the use-case?
I always thought this interface is only being used by LVM.

Thanks,
//richard