From mboxrd@z Thu Jan 1 00:00:00 1970 From: Al Viro Subject: Re: [PATCH resend] fs/proc: Move kfree outside pde_unload_lock Date: Fri, 5 Apr 2013 18:36:23 +0100 Message-ID: <20130405173623.GE4068@ZenIV.linux.org.uk> References: <515D9F8A.2060505@sgi.com> <1365090819-25448-1-git-send-email-nzimmer@sgi.com> <20130404161140.GR21522@ZenIV.linux.org.uk> <515DB465.1060004@sgi.com> <20130404204459.GU21522@ZenIV.linux.org.uk> <515F0456.9040803@sgi.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: akpm@linux-foundation.org, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, "Eric W. Biederman" , David Woodhouse , stable@vger.kernel.org To: Nathan Zimmer Return-path: Content-Disposition: inline In-Reply-To: <515F0456.9040803@sgi.com> Sender: stable-owner@vger.kernel.org List-Id: linux-fsdevel.vger.kernel.org On Fri, Apr 05, 2013 at 12:05:26PM -0500, Nathan Zimmer wrote: > On 04/04/2013 03:44 PM, Al Viro wrote: > >On Thu, Apr 04, 2013 at 12:12:05PM -0500, Nathan Zimmer wrote: > > > >>Ok I am cloning the tree now. > >>It does look like the patches would conflict. > >>I'll run some tests and take a deeper look. > >FWIW, I've just pushed there a tentative patch that switches to hopefully > >saner locking (head should be at cb673c115c1f99d3480471ca5d8cb3f89a1e3bee). > >Is that more or less what you want wrt spinlock contention? > > > >One note: for any given pde_opener, close_pdeo() can be called at most > >by two threads - final fput() and remove_proc_entry() resp. I think > >the use of completion + flag is safe there; pde->pde_unload_lock > >should serialize the critical areas. > > Something isn't quite right. I keep getting hung during boot. > dracut: Mounted root filesystem /dev/sda8 > dracut: Switching root > > I'll try to get some more info on a smaller box. Umm... Try to add WARN_ON(1) in entry_rundown(), just to see what's getting hit (don't bother with entry name, stack trace will be enough).