From mboxrd@z Thu Jan 1 00:00:00 1970 MIME-Version: 1.0 In-Reply-To: References: Date: Tue, 4 Aug 2009 16:49:56 -0700 Message-ID: Subject: Re: [9fans] p9p acme freezes when ctrl-f inside its mounted directory From: Russ Cox To: Fans of the OS Plan 9 from Bell Labs <9fans@9fans.net> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Topicbox-Message-UUID: 388d0ee4-ead5-11e9-9d60-3106f5b1d025 On Tue, Aug 4, 2009 at 10:33 AM, Rudolf Sykora wrote: > I noticed that when running acme in plan9port and having its > directories mounted say on /mnt/acme, then if I try from within a win > window in the acme to auto-complete a directory name---I am in /mnt, I > type 'a' and hit the 'insert' key or ctrl-f, or I am anywhere inside > the acme filesystem---the program freezes (though, if I write it > myself, I can cd to the acme directory). The problem is that acme is basically a single operating system thread, and that operating system thread is trying to look in /mnt/acme. To serve that request, the kernel has posted a FUSE message to acme to handle, which acme will get around to just as soon as the system call in /mnt/acme finishes. Deadlock. This is not a problem on Plan 9 because acme does not put itself in its own name space. On Linux, where there is just one big name space, more care is necessary (and not implemented). Russ