On 15/02/2023 3:10 pm, Jan Beulich wrote: > Besides a printk() the main effect is slight corruption of the start > info magic: While that's meant to be xen-3.0-x86_64, it wrongly ended > up as xen-3.0-x86_64p. > > Fixes: 460060f83d41 ("libelf: use for x86 dom0 builder") > Signed-off-by: Jan Beulich <jbeul...@suse.com> > --- > RFC: While Linux works fine with the adjustment, I'm not entirely > certain of external tools (kexec?) having grown a dependency.
Again, I wonder why you think regular kexec has any anything to do with this? Are you mixing it up with (legacy) pvgrub which does end up doing a kexec inside the context of a PV guest? If so, it's MiniOS's support you need to care about, and I cant see any logic that even inspects the start_info->magic[] (either in MiniOS itself, or the pvgrub patches). Like plenty of other fields in the undocumented PV ABI, it's not interesting at all to software. There's nothing I can see in it that you don't know at compile time. > It > may be worth noting that XenoLinux and its forward ports never had > this ELF note in 64-bit kernels, so in principle it may be > reasonable to expect that no such dependency exists anywhere. NetBSD sets PAE_MODE for 32bit and 64bit but, like everything else, doesn't appear to inspect start_info->magic[]. xen-3.0-x86_64p is obviously bogus. I find it far more likely that noone has ever noticed this bug, than anyone gaining a dependency on it. Insert usual rant about the PV ABI being entirely undocumented... ~Andrew