linux-kernel - Re: [RFC] module: add per-module params lock

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: <87mw0ft283.fsf@rustcorp.com.au>
Date:	Fri, 05 Jun 2015 10:12:36 +0930
From:	Rusty Russell <rusty@...tcorp.com.au>
To:	Dan Streetman <ddstreet@...e.org>
Cc:	Jani Nikula <jani.nikula@...el.com>,
	Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
	"David S. Miller" <davem@...emloft.net>,
	Christoph Hellwig <hch@...radead.org>,
	Andrew Morton <akpm@...ux-foundation.org>,
	linux-kernel@...r.kernel.org, Dan Streetman <ddstreet@...e.org>
Subject: Re: [RFC] module: add per-module params lock

Dan Streetman <ddstreet@...e.org> writes:
> I sent this as part of a patch series a few days ago, which I was asked to
> break up, so I'm sending only this patch as a RFC now, until I work out
> the details of the zswap patch that needs this.  I'd like to get comments
> on this early, since it changes the way module param locking is done.

OK, it's not insane, but I'm not entirely convinced.

1) The difference between blocking sysfs for read vs write is mainly
   documentation.  In theory, it allows a rwsem, though in practice it's
   not been a bottleneck to now.

2) Implicit is bad: implying the module rather than the parameter is
   weird, and skips the BUG_ON() check which was there before.

And finally, why are you loading a module from a param callback?  That's
a first!

Thanks,
Rusty.
--
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/