On Mon, Jan 25, 2021 at 03:54:31PM +0800, Nicolas Boichat wrote: > Hi copy_file_range experts, > > We hit this interesting issue when upgrading Go compiler from 1.13 to > 1.15 [1]. Basically we use Go's `io.Copy` to copy the content of > `/sys/kernel/debug/tracing/trace` to a temporary file. Nit, the above file is NOT a sysfs file. Odds are it is either a debugfs, or a tracefs file, please check your mounts to determine which it is, as that matters a lot on the kernel backend side for trying to figure out what is going on here :) thanks, greg k-h
