From: 'Joerg Roedel' > Sent: 20 August 2021 09:52 > > On Fri, Aug 20, 2021 at 08:43:47AM +0000, David Laight wrote: > > Hmmm... > > If Linux needs its own IDT then temporarily substituting the old IDT > > prior to a UEFI call will cause 'grief' if a 'Linux' interrupt > > happens during the UEFI call. > > This is neede only during very early boot before Linux called > ExitBootServices(). Nothing that causes IRQs is set up by Linux yet. Of > course the Firmware could have set something up, but Linux runs with > IRQs disabled when on its own IDT at that stage. So allocate and initialise the Linux IDT - so entries can be added. But don't execute 'lidt' until later on. David - Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK Registration No: 1397386 (Wales)
