Messages in this thread | | | Subject | Re: [PATCH 3/3] x86: context_tracking: avoid irq_save/irq_restore on kernel entry and exit | From | Paolo Bonzini <> | Date | Tue, 15 Mar 2016 09:51:49 +0100 |
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On 14/03/2016 20:23, Andy Lutomirski wrote: > On Tue, Oct 27, 2015 at 10:22 PM, Andy Lutomirski <luto@amacapital.net> wrote: >> On Tue, Oct 27, 2015 at 6:39 PM, Paolo Bonzini <pbonzini@redhat.com> wrote: >>> x86 always calls user_enter and user_exit with interrupt disabled. >>> Therefore, it is not necessary to check for exceptions, nor to >>> save/restore the IRQ state, when context tracking functions are >>> called by guest_enter and guest_exit. >>> >>> Use the previously introduced __context_tracking_entry and >>> __context_tracking_exit. >> >> x86 isn't ready for this yet. We could do a quick-and-dirty fix with >> explicit IRQs-on-and-off much protected by the static key, or we could >> just wait until I finish the syscall cleanup. I favor the latter, but >> you're all welcome to do the former and I'll review it. >> > > Once Linus pulls tip:x86/asm, x86 should be ready for this. Want to try again?
Yup, it's on my todo list. :)
Paolo
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