On Wed, Feb 3, 2021 at 5:04 PM Greg KH <gregkh@xxxxxxxxxxxxxxxxxxx> wrote: > > 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 :) Yes yes it's tracefs ,-) But, from the other thread https://lkml.org/lkml/2021/1/26/2029 sysfs (and any other fs that generates files dynamically like procfs) would likely hit issues as well (but maybe in more rare circumstances). Thanks! > > thanks, > > greg k-h
