[<prev] [next>] [<thread-prev] [day] [month] [year] [list]
Message-ID: <20080110204020.GC20152@skl-net.de>
Date: Thu, 10 Jan 2008 21:40:20 +0100
From: Andre Noll <maan@...temlinux.org>
To: Boaz Harrosh <bharrosh@...asas.com>
Cc: Andi Kleen <andi@...stfloor.org>,
James Bottomley <James.Bottomley@...senPartnership.com>,
linux-scsi <linux-scsi@...r.kernel.org>,
linux-kernel <linux-kernel@...r.kernel.org>,
kernel-janitors@...r.kernel.org,
Richard Knutsson <ricknu-0@...dent.ltu.se>
Subject: Re: [patch 1/1] Switch ioctl functions of drivers/scsi/sg.c to unlocked_ioctl
On 22:13, Boaz Harrosh wrote:
> All the scsi calls do not need any locks. The scsi LLDS never
> see these threads since commands are queued through the block
> layer.
That's what everybody believes, but nobody seems to know for sure.
Therefore I did what Andi suggested: Make a zero-semantics change
that moves the lock_kernel() to sg_ioctl() to make people aware of
the fact that this function runs under the BKL. At least the latter
has already succeeded.
> What's left is what you see, here in sg.c. you must have the best
> knowledge about the possible races between ioctl and open/release
> and probe/remove. And all these put_user() copy_user() etc...
> Why don't you have a hard look and fix them properly.
Because that requires much more knowledge. Al is looking into this
which indicates that it is non-trivial issue. I am clearly not the
right person to decide this question.
> please don't *lock_kernel();* for scsi's sake.
The BKL was there all the time. My patch just made it more visable
to the scsi people by moving it into sg.c.
Andre
--
The only person who always got his work done by Friday was Robinson Crusoe
Download attachment "signature.asc" of type "application/pgp-signature" (190 bytes)
Powered by blists - more mailing lists