On Wed, Mar 03, 2021 at 03:37:40PM -0500, Steven Rostedt wrote: > On Wed, 03 Mar 2021 12:13:08 -0800 > "Daniel Xu" <dxu@xxxxxxxxx> wrote: > > > On Wed, Mar 3, 2021, at 11:58 AM, Daniel Xu wrote: > > > On Wed, Mar 03, 2021 at 09:26:04AM -0500, Steven Rostedt wrote: > > > > On Wed, 3 Mar 2021 13:48:28 +0900 > > > > Masami Hiramatsu <mhiramat@xxxxxxxxxx> wrote: > > > > > > > > > > > > > > > > > > > > > I think (can't prove) this used to work: > > > > > > > > Would be good to find out if it did. > > > > > > I'm installing some older kernels now to check. Will report back. > > > > Yep, works in 4.11. So there was a regression somewhere. > > Care to bisect? ;-) Took a while (I'll probably be typing "test_regression.sh" in my sleep tonight) but I've bisected it down to f95b23a112f1 ("Merge branch 'x86/urgent' into x86/asm, to pick up dependent fixes"). I think I saw the default option for stack unwinder change from frame pointers -> ORC so that may be the root cause. Not sure, though. Need to look more closely at the commits in the merge commit. <...> Daniel