From mboxrd@z Thu Jan 1 00:00:00 1970 From: Greg KH Date: Fri, 26 Mar 2004 23:05:32 +0000 Subject: Re: [PATCH] USB hotplug race Message-Id: <20040326230532.GF31372@kroah.com> List-Id: References: <20040317142717.GA14149@pasky.ji.cz> In-Reply-To: <20040317142717.GA14149@pasky.ji.cz> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: linux-hotplug@vger.kernel.org On Wed, Mar 17, 2004 at 03:27:17PM +0100, Petr Baudis wrote: > Hello, > > so I finally upgraded from 2.4 to 2.6 (2.6.4), and one of the few > problems I've hit is hotplug. Basically, when I start up hotplug while > my Zaurus is plugged, everything works fine and usbnet gets loaded, > however when I plug Zaurus after hotplug was loaded, it trashes the > event. > > After populating the hotplug scripts with plethora of debug prints, > I've tracked it down to usb_convert_vars() - basically, immediatelly > after the USB device is plugged and the signal is already delivered to > hotplug, the sysfs tree isn't yet populated by all the relevant data > and only detach_state is present there - no bDeviceClass or so. Yes, it's quite easy to race the kernel with this. But how about putting the proper patch in by sitting and spinning until we see the file we are looking for (or erroring out after a time period.) That's much cleaner than always sleeping. On a SMP box, you usually never need to sleep :) thanks, greg k-h ------------------------------------------------------- This SF.Net email is sponsored by: IBM Linux Tutorials Free Linux tutorial presented by Daniel Robbins, President and CEO of GenToo technologies. Learn everything from fundamentals to system administration.http://ads.osdn.com/?ad_id70&alloc_id638&op=click _______________________________________________ Linux-hotplug-devel mailing list http://linux-hotplug.sourceforge.net Linux-hotplug-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/linux-hotplug-devel