Messages in this thread | | | Date | Tue, 22 Nov 2011 23:28:31 -0800 | Subject | Re: tty related lockdep trace during bootup on 3.2-rc2 | From | Havard Skinnemoen <> |
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On Tue, Nov 22, 2011 at 7:38 PM, Dave Jones <davej@redhat.com> wrote: > From Linus' current tree... > > related to 5dc2470c602da8851907ec18942cd876c3b4ecc1 maybe ?
Yes, probably. I did have a bad feeling about the locking, but it seemed to behave well during testing. Wonder why I didn't see this.
So what's happening is that tty_open() holds big_tty_mutex while calling acm_tty_open which takes open_lock, and acm_tty_close holds open_lock while calling tty_port_close_start which takes big_tty_mutex?
Not sure how to solve this. Not taking the lock before calling tty_port_close_start means the tty_port may get freed before it returns.
Havard
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