Re: [PATCH/RFC 2.6.21 3/5] ehca: completion queue: remove use of do_mmap()

• To: Nathan Lynch <[email protected]>
• Subject: Re: [PATCH/RFC 2.6.21 3/5] ehca: completion queue: remove use of do_mmap()
• From: Roland Dreier <[email protected]>
• Date: Thu, 11 Jan 2007 11:56:18 -0800
• Authentication-results: sj-dkim-2; [email protected]; dkim=pass ( sig from cisco.com/sjdkim2002 verified; );
• Cc: Christoph Hellwig <[email protected]>, Hoang-Nam Nguyen <[email protected]>, [email protected], [email protected], [email protected], [email protected], [email protected]
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• In-reply-to: <20070111194054.GA11770@localdomain> (Nathan Lynch's message of "Thu, 11 Jan 2007 13:40:54 -0600")
• References: <[email protected]> <[email protected]> <20070111194054.GA11770@localdomain>
• Sender: [email protected]
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 > >  	spin_lock_irqsave(&ehca_cq_idr_lock, flags);
 > >  	while (my_cq->nr_callbacks)
 > >  		yield();

 > Isn't that code outright buggy?  Calling into the scheduler with a
 > spinlock held and local interrupts disabled...

Yes, absolutely -- if nr_callbacks is ever nonzero then this will
obviously crash instantly.

 - R.
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• Follow-Ups:
  • Re: [PATCH/RFC 2.6.21 3/5] ehca: completion queue: remove use of do_mmap()
    • From: Hoang-Nam Nguyen <[email protected]>

• References:
  • [PATCH/RFC 2.6.21 3/5] ehca: completion queue: remove use of do_mmap()
    • From: Hoang-Nam Nguyen <[email protected]>
  • Re: [PATCH/RFC 2.6.21 3/5] ehca: completion queue: remove use of do_mmap()
    • From: Christoph Hellwig <[email protected]>
  • Re: [PATCH/RFC 2.6.21 3/5] ehca: completion queue: remove use of do_mmap()
    • From: Nathan Lynch <[email protected]>

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