Re: BUG: drivers/md/bcache/writeback.c:237

[Marc MERLIN <marc@merlins.org>]

On Wed, Feb 24, 2016 at 06:53:05AM +0000, Eric Wheeler wrote:
> Be sure to cherry-pick these from linux 4.5-rc1:
> 	git cherry-pick 2ef9ccbf~1..627ccd20
> or use one of the 4.1 or 3.18 longterm kernels.
 
So, I added these patches to my 4.4.2 kernel, but it still crashes when
seeing one cache device at boot.

Crash:
https://goo.gl/photos/8H1DtYjSijK4ngFv6

	while (!kthread_should_stop()) {
		try_to_freeze();

		w = bch_keybuf_next(&dc->writeback_keys);
		if (!w)
			break;

>>>>>		BUG_ON(ptr_stale(dc->disk.c, &w->key, 0));

		if (KEY_START(&w->key) != dc->last_read ||

I have to remove the partition for my system to boot.

Before I destroy it, any other patches I should try?

And to be fair, it's a huge pain to deal with this, there should be an
easier way to just turn bcache off from the kernel command line. In this
case it was really a lot of work to get back to even a booting system.

You also said:
> 4.1.18 has the patches, so unless there is something specific in 4.4 that
> you need, I recommend 4.1.  We've been running 4.1.17 with patches in
> production for a while and it works great.  Haven't tried vanilla 4.1.18
> yet, but I plan to soon.

Sadly, I run btrfs, I can't just go to random old kernels like this.
Is bcache not stable in up to date kernels?

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/                         | PGP 1024R/763BE901