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Sender: Corey Minyard <tcminyard@gmail.com>
Date:   Tue, 4 Jul 2023 09:27:47 -0500
From:   Corey Minyard <minyard@acm.org>
To:     Andrew Jeffery <andrew@aj.id.au>
Cc:     openipmi-developer@lists.sourceforge.net,
        linux-kernel@vger.kernel.org, Chengfeng Ye <dg573847474@gmail.com>
Subject: Re: [PATCH] ipmi: fix potential deadlock on &kcs_bmc->lock
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On Fri, Jun 30, 2023 at 10:31:02AM +0930, Andrew Jeffery wrote:
> Hi Corey, Chengfeng,
> 
> On Wed, 28 Jun 2023, at 21:17, Corey Minyard wrote:
> > Indeed, this looks like an issue.
> >
> > Andrew, any opinions on this?  The attached patch will work, the other
> > option would be to disable interrupts when calling
> > kcs_bmc_handle_event() in the timer handler.  But then you have to worry
> > about RT.
> 
> Right, I think we'd do best to not over-complicate things.
> spin_lock_irq{save,restore}() are the intuitive choice to me.
> 
> I'll follow up with R-b/T-b tags once I've booted the patch
> and done some testing.

Thanks.  This is in my for-next tree, I'd like to get this in the merge
window, which I believe ends this Sunday.

> >> This flaw was found using an experimental static analysis tool we are
> >> developing for irq-related deadlock.

Will this tool be available for general use?  It's obviously quite
handy.

-corey