On Mon, 28 Aug 2017 15:06:00 +0200, Adam Borowski wrote: > > On Mon, Aug 28, 2017 at 02:26:06PM +0200, Takashi Iwai wrote: > > I seem to get a kernel warning when running KVM on Dell desktop with > > IvyBridge like below. As you can see, a bad page BUG is triggered > > after that, too. The problem is not triggered always, but it happens > > occasionally. > > See the thread starting with 20170820231302.s732zclznrqxwr46@xxxxxxxxxx > > > I haven't seen this on 4.13-rc4 at all, and IIRC, it started happening > > since rc5. So this might be a regression at rc5. But, as it doesn't > > happen always, I can't be 100% sure about it, and it's quite difficult > > to bisect (the test case isn't reliable), unfortunately. > > Same here -- it sometimes takes a few hours of trying to reproduce, which > makes proving the negative greatly unpleasant. > > And all I've been able to tell so far is that the problem is between > 4.13-rc4 and 4.13-rc5, just like you say. Good to hear that we can chorus! So if it's really a regression between rc4 and rc5, I see no obvious changes in arch/x86, i.e. it's likely somewhere else. (snip) > The first WARN is always the above. But the rest seems to be totally random > -- a nasty case of fandango on core whose results range from harmless > through crash to massive data loss (just guess what would happen if some > idiot picked balancing the disk as a test load -- no one would be that > stupid, right? At least an incomplete idiot has checksums and backups). Yeah, the crash after the WARNING seems quite random. thanks, Takashi
