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From: Russ Cox <rsc@swtch.com>
To: Fans of the OS Plan 9 from Bell Labs <9fans@9fans.net>
Subject: Re: [9fans] lock diagnostics on Fossil server
Date: Tue, 26 Oct 2010 07:28:57 -0700	[thread overview]
Message-ID: <AANLkTi=7imoeJdo34T3wq5EYkihYwH5LnL36FJQ63jPK@mail.gmail.com> (raw)
In-Reply-To: <6701519c3b154bfb8462542b787fbae5@coraid.com>

> sounds familiar.  this patch needs to be applied to the kernel:

Like Lucio and Cinap, I am skeptical that this is the fix.

It's a real bug and a correct fix, as we've discussed before,
but if the kernel loses this race I believe it will crash dereferencing nil.
Lucio showed a kernel that was very much still running.

... unless the Plan 9 kernel has changed since I last worked on it
and now kills only the current process when a bad kernel memory
access happens (this is what Linux does, but I think that's
very questionable behavior).

Russ


  parent reply	other threads:[~2010-10-26 14:28 UTC|newest]

Thread overview: 13+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2010-10-24 12:20 Lucio De Re
2010-10-25 13:20 ` erik quanstrom
2010-10-25 14:35   ` Lucio De Re
2010-10-26  2:01   ` cinap_lenrek
2010-10-26 12:44     ` erik quanstrom
2010-10-26 13:45       ` Lucio De Re
2010-10-26 14:31         ` erik quanstrom
2010-10-26 14:28   ` Russ Cox [this message]
2010-10-26 14:48     ` erik quanstrom
2010-10-26 16:27     ` Lucio De Re
2010-10-26 17:01       ` erik quanstrom
2010-10-27  3:03         ` lucio
2010-10-27  4:14           ` erik quanstrom

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