On 05.09.2024 15:06, Andrew Cooper wrote: > asm/config.h is included in every translation unit (via xen/config.h), while > only a handful of functions actually interact with the trampoline. > > Move the infrastructure into its own header, and take the opportunity to > document everything. > > Also change trampoline_realmode_entry() and wakeup_start() to be nocall > functions, rather than char arrays. > > No functional change. > > Signed-off-by: Andrew Cooper <andrew.coop...@citrix.com>
Reviewed-by: Jan Beulich <jbeul...@suse.com> > --- /dev/null > +++ b/xen/arch/x86/include/asm/trampoline.h > @@ -0,0 +1,98 @@ > +/* SPDX-License-Identifier: GPL-2.0-or-later */ > +#ifndef XEN_ASM_TRAMPOLINE_H > +#define XEN_ASM_TRAMPOLINE_H Not exactly usual a guard name, but once the new naming scheme is finalized most will need renaming anyway. > +/* > + * Calculate the physical address of a symbol in the trampoline. > + * > + * Should only be used on symbols declared later in this header. Specifying > + * other symbols will compile but malfunction when used, as will using this > + * helper before the trampoline is placed. > + */ As to the last point made - we could of course overcome this by setting trampoline_phys to a suitable value initially, and only to its low-mem value once the trampoline was moved there. As to compiling but malfunctioning - I'd kind of expect relocation overflows to be flagged by the linker. Jan
