Kent Overstreet - 06.10.24, 19:18:00 MESZ: > > I still do have a BCacheFS on my laptop for testing, but meanwhile I > > wonder whether some of the crazy kernel regressions I have seen with > > the last few kernels where exactly related to having mounted that > > BCacheFS test filesystem. I am tempted to replace the BCacheFS with a > > BTRFS just to find out. > > I think you should be looking elsewhere - there have been zero reports > of random crashes or anything like what you're describing. Even in > syzbot testing we've been pretty free from the kind of memory safety > issues that would cause random crashes
Okay. From what I saw of the backtrace I am not sure it is a memory safety bug. It could be a deadlock thing with work queues. Anyway… as you can read below it is not BCacheFS related. But I understand too little about all of this to say for sure. > The closest bugs to what you're describing would be the > __wait_on_freeing_inode() deadlock in 6.12-rc1, and the LZ4HC crash that > I've yet to triage - but you specifically have to be using lz4:15 > compression to hit that path. Well a crash on reboot happened again, without BCacheFS. I wrote that I report back, either case. I think I will wait whether this goes away with a newer kernel as some of the other regressions I saw before. It was not in all of the 6.11 series of Debian kernels but just in the most recent one. In case it doesn't I may open a kernel bug report with Debian directly. For extra safety I did a memory test with memtest86+ 7.00. Zero errors. As for one of the other regressions I cannot tell yet, whether they have gone away. So far they did not occur again. But so far it looks that replacing BCacheFS with BTRFS does not make a difference. And I wanted to report that back. Best, -- Martin
