On Mon, Jun 11, 2018 at 01:59:15PM +0000, Jeremy Cline wrote: > A user has bisected the problem to the v4.16 commit 1ab4ca7c59d4 > ("x86/tsc: Fix mark_tsc_unstable()"). According to the reporter, > explicitly setting "tsc=" on the kernel command line causes the boot to > always succeed. All the users have Thinkpad T500s or T400s (Core 2 Duos) Weird. So Core2 typically triggers mark_tsc_unstable() in either intel_idle or processor_idle. ISTR testing that when I did the patches. When I make that mark_tsc_unstable() in the idle drivers unconditional and boot my ivb with that, it doesn't want to fail. I've booted the machine 5 consequctive times without issue. Let me try and checkout -stable, maybe something's up with that.