On Sat, Aug 4, 2018 at 3:37 AM, Konstantin Belousov <kostik...@gmail.com> wrote: > On Fri, Aug 03, 2018 at 11:27:02PM -0500, Kyle Evans wrote: >> >> This seems odd- pmap lock is acquired at [1], then asserted shortly >> later at [2]... I avoid some of this stuff as well as I can, but is it >> actually possible for PCPU_GET(...) acquired curpmap to not match >> curthread->td_proc->p_vmspace->vm_pmap in this context? >> >> [1] >> https://svnweb.freebsd.org/base/head/sys/dev/efidev/efirt.c?view=markup#l260 >> [2] >> https://svnweb.freebsd.org/base/head/sys/amd64/amd64/efirt_machdep.c?view=markup#l254 > There could be that curpcpu not yet synced with proc0 pmap. It could be > fixed. > > But it is not clear to me why efi_arch_enter() is called there. I see > the check for GetTime belonging to the range described by a map descriptor. > I do not see why do you need an enter into the EFI context for comparing > integers.
This probably could have been documented better, but efi_runtime pointer may (always?) point into runtime service memory that isn't valid/available at that point, so we get a fault and panic when dereferencing it to grab rt_gettime address. We ran into this wall when adding the check originally. _______________________________________________ freebsd-current@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/freebsd-current To unsubscribe, send any mail to "freebsd-current-unsubscr...@freebsd.org"
