On 05/02/2018 04:26 AM, Jan Beulich wrote: >>>> On 01.05.18 at 14:34, <boris.ostrov...@oracle.com> wrote: >> On 05/01/2018 04:00 AM, Roger Pau Monné wrote: >>> On Mon, Apr 30, 2018 at 12:23:39PM -0400, Boris Ostrovsky wrote: >>>> And without it we can't use _BOOT_XX macros any longer so define new ones. >>> Not being that familiar with Linux internals I'm not sure I see the >>> benefit of this. Isn't there a risk that some other code is going to >>> use the __BOOT_XX defines? >> The startup code we are jumping to loads their own GDT and I don't see >> any explicit references to segments. > No explicit references to segments isn't enough: You also need to make > sure no exceptions at all can occur while loaded selectors and GDT are > out of sync - in particular NMI might be of concern here (this isn't PV > after all, where not having a callback registered effectively masks NMI).
How would keeping __BOOT_XX selectors help with NMI? We don't have anything set up for NMI handling anyway yet, this is all done in x86 startup code later. -boris _______________________________________________ Xen-devel mailing list Xen-devel@lists.xenproject.org https://lists.xenproject.org/mailman/listinfo/xen-devel
