Hi Andrew, Xen Development team. I compiled and installed Xen by appending -fcf-protection=none to CFLAGS on Ubuntu 20.04 but it still crashes on startup.
On Wed, Apr 29, 2020 at 10:58 PM Ayush Dosaj <[email protected]> wrote: > Awesome, thanks! > > On Wed, Apr 29, 2020 at 10:55 PM Andrew Cooper <[email protected]> > wrote: > >> On 29/04/2020 18:17, Ayush Dosaj wrote: >> > Hi Xen development team, >> > >> > I am Ayush. I compiled Xen Hypervisor from source on Ubuntu 20.04 >> > machine running on an intel-i9 CPU. >> > I am getting compilation error due to the following two flags. >> > Error: error: ‘-mindirect-branch’ and ‘-fcf-protection’ are not >> compatible. >> > >> > Complete Error logs can be found at >> https://paste.ubuntu.com/p/xvvyPnhW5c/ >> > >> > And when I compiled Xen commenting the two flags in Rules.mk file, it >> > compiles and installs properly but on boot-up i see a blank black screen >> > and i am stuck there. >> >> That is a GCC bug (these options are actually fine in combination). It >> got fixed earlier today in master, and backported for GCC 9.4 >> >> You can work around it by appending -fcf-protection=none to CFLAGS >> >> I wouldn't try editing the logic around -mindirect-branch, as that is >> related to retpoline safety for Spectre v2, and probably relies on the >> build matching the code. >> >> ~Andrew >> > > > -- > Ayush Dosaj > VIT Vellore > > -- Ayush Dosaj
