On Thu, 25 Feb 2016, Marc MERLIN wrote: > On Thu, Feb 25, 2016 at 06:18:03PM +0800, Zhu Yanhai wrote: > > Marc, > > When did you *first* see this BUG_ON? During boot up or far after the > > whole system is up? > > I setup bcache, had it work a bit. > During shutdown, it crapped out when syncing/unmounting Do you have more information about what crapped out on shutdown? Memory? IO Error? Just hung so the reset button was pushed? Was there a backtrace? It might be a good idea to use netconsole and point it at a syslog server to catch the whole backtrace. > After each subsequent boot, the system crashed as soon as the module loaded > and scanned my disks. So just to clarify, the current BUG_ON discussed is happening at boot, and is not the mid-shutdown error that first happened? -Eric > > While I understand I did hit a bug, I've been on a cruisade to get BUG_ON > removed from btrfs code and replaced with warns/abort/remount read only. > On a production system, BUG_ON really sucks, especially if it happens as > soon as the kernel loads and before you can even do anything to fix the > issue :) > > If there is any chance this can be changed into some kind of abort that > disables bcache or just prevents bcache from making damaging writes to the > backing device, by simply disabling the cache, that would be much better :) > > In the meantime, I've stopped using writeback since it seems that it's been > the reason why I hit this problem. > > Thanks, > Marc > -- > "A mouse is a device used to point at the xterm you want to type in" - A.S.R. > Microsoft is to operating systems .... > .... what McDonalds is to gourmet cooking > Home page: http://marc.merlins.org/ > -- To unsubscribe from this list: send the line "unsubscribe linux-bcache" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
