On 20.05.21 14:08, Jan Beulich wrote: > On 20.05.2021 13:57, Juergen Gross wrote: >> On 20.05.21 13:42, Jan Beulich wrote: >>> xen_setup_gdt(), via xen_load_gdt_boot(), wants to adjust page tables. >>> For this to work when NX is not available, x86_configure_nx() needs to >>> be called first. >>> >>> Reported-by: Olaf Hering >>> Signed-off-by: Jan Beulich >> >> Reviewed-by: Juergen Gross > > Thanks. I guess I forgot > > Cc: stable@vger.kernel.org > > If you agree, can you please add this before pushing to Linus? Uh, just had a look why x86_configure_nx() was called after xen_setup_gdt(). Upstream your patch will be fine, but before kernel 5.9 it will break running as 32-bit PV guest (see commit 36104cb9012a82e7). So I will take your patch as is, but for kernels 5.8 and older I recommend a different approach by directly setting the NX capability after checking the cpuid bit instead of letting that do get_cpu_cap(). Juergen