On 11/01/2017 02:01 PM, Thomas Gleixner wrote: > On Tue, 31 Oct 2017, Dave Hansen wrote: >> >> + pushq %rdi >> + SWITCH_TO_KERNEL_CR3 scratch_reg=%rdi >> + popq %rdi > > Can you please have a macro variant which does: > > SWITCH_TO_KERNEL_CR3_PUSH reg=%rdi > > So the pushq/popq is inside the macro. This has two reasons: > > 1) If KAISER=n the pointless pushq/popq go away > > 2) We need a boottime switch for that stuff, so we better have all > related code in the various macros in order to patch it in/out.
After Boris's comments, these push/pops are totally unnecessary. We just delay the CR3 until after we stashed off pt_regs and are allowed to clobber things. > Also, please wrap these macros in #ifdef KAISER right away and provide the > stubs as well. It does not make sense to have them in patch 7 when patch 1 > introduces them. Will do.
