On 14.03.2024 14:01, Jason Andryuk wrote: > On 2024-03-14 03:11, Jan Beulich wrote: >> On 13.03.2024 20:30, Jason Andryuk wrote: >>> A new ELF note will specify the alignment for a relocatable PVH kernel. >>> ELF notes are suitable for vmlinux and other ELF files, so this >>> Linux-specific bzImage parsing in unnecessary. >> >> Hmm, shouldn't the order of attempts to figure the alignment be ELF note, >> ELF header, and then 2Mb? > > This patch series makes Xen only relocate when the ELF Note is present. > Linux PVH entry points today are not relocatable, so that needs to be > specified some way. This new note also includes the alignment, so there > is no need to try other means of obtaining the alignment.
Going yet beyond what I said in reply to the patch: The mere presence of the note, with no data at all, could be sufficient to indicate the kernel is relocatable, when no other restrictions (min, max, align) apply. > Also, the ELF header values didn't change with CONFIG_PHYSICAL_ALIGN, so > that didn't seem reliable. Well, that's an observation for Linux. But the interface here ought to be OS-agnostic. Jan
