On 2/21/19 8:48 AM, Peter Zijlstra wrote: > On Thu, Feb 21, 2019 at 08:12:25AM -0500, Prarit Bhargava wrote: >> Users cannot disable multiple CPU features with the kernel parameter >> clearcpuid=. For example, "clearcpuid=154 clearcpuid=227" only disables >> CPUID bit 154. >> >> Previous to commit 0c2a3913d6f5 ("x86/fpu: Parse clearcpuid= as early XSAVE >> argument") it was possible to pass multiple clearcpuid options as kernel >> parameters using individual entries. With the new code it isn't easy to >> replicate exactly that behaviour but a comma separated list can be easily >> implemented, eg) "clearcpuid=154,227" >> >> Make the clearcpuid parse a comma-separated list of values instead of only >> a single value. > > Can we also please kill the value thing entirely and only accept > strings. Having to reverse engineer the numbers is madness. > > Also, wth would you want to disable XSAVE and EPB ? > It looks like Fenghua has implemented this here: https://marc.info/?l=linux-kernel&m=154908490105208&w=2 so please drop this patch. Thanks, P.