lkml.org 
[lkml]   [2003]   [Aug]   [3]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectIDE locking problem
From
Date
Hi Alan & Bart !

While fixing my hotswap media-bay IDE controller for 2.6, I found
a locking problem with IDE (again ? :) in ide_unregister_hw. Basically
the problem is that it calls blk_cleanup_queue(), which is unsafe to
call with a lock held (it will call flush_workqueue() at one point).
Other side effect, flush_workqueue() will re-enable IRQs, thus allowing
us to get an IRQ while holding the spinlock -> double lock, but that's
just a side effect of calling flush_workqueue in that context.

So the call to blk_cleanup_queue() shall be moved outside of the
spinlock. I don't know much about the BIO details, is it possible
to first unregister_blkdev, then only call blk_cleanup_queue() ? That
would help making sure we don't get a request sneaking in ?

Ben.


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

\
 
 \ /
  Last update: 2005-03-22 13:47    [W:0.072 / U:0.680 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site