Re: [Nbd] nbd-client and SIGSTOP/SIGCONT

[Wouter Verhelst <w@...112...>]

On Mon, Apr 18, 2011 at 10:02:35PM -0400, Paul Clements wrote:
> On Mon, Apr 18, 2011 at 11:44 AM, Ian <coughlan@...866...> wrote:
> 
> > Thanks for the patch.  This same thing was the first thing I tried, but
> > quickly realized that more was needed.  When -ERESTARTSYS is returned
> > (without first shutting down the socket), we re-enter the ioctl, create
> > another thread, and that thread prints out "nbd3: wrong magic", terminates,
> > and we return -EPROTO to the client, which also terminates, and the block IO
> > is hosed.
> 
> Ah, yep....
> 
> > I think I might just hack killall5 for now, to prevent it from sending the
> > SIGSTOP/SIGCONT to nbd.
> 
> That is not a bad idea. A much easier hack than making nbd-client
> re-entrant, I must admit.

It's basically what I do to make root-on-NBD work in Debian; there's a
/lib/init/rw/sendsigs.omit.d directory in Debian where you can write PID
files for processes that you don't want killall5 to destroy.

-- 
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the following formula:

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