On Sun, 10 Mar 2019, Linus Torvalds wrote: > On Sun, Mar 10, 2019 at 4:33 AM Thomas Gleixner <t...@linutronix.de> wrote: > Finally, I suspect this is all subtly buggy anyway, because your > 'cr4_pin' thing is a global variable, but the cr4 bits are per-cpu, > and I don't see how this works with the different CPU's setting things > up one after each other, but the first one sets the pinned bits. > > So it basically "pins" the bits on CPU's before they are ready, so the > secondary CPU's maghically get the bits set _independently_ of running > the actual setup code to set them. That may *work*, but it sure looks > iffy.
Which I looked at and it's a non issue. The SMAP/SMEP settings are globally the same and the non-boot CPUs set the bits very early in the boot process. Thanks, tglx