On 06/09/2022 11:41, Evgeniy Baskov wrote: > diff --git a/arch/x86/boot/compressed/head_64.S b/arch/x86/boot/compressed/head_64.S > index 5273367283b7..889ca7176aa7 100644 > --- a/arch/x86/boot/compressed/head_64.S > +++ b/arch/x86/boot/compressed/head_64.S > @@ -602,6 +603,28 @@ SYM_FUNC_START_LOCAL_NOALIGN(.Lrelocated) > jmp *%rax > SYM_FUNC_END(.Lrelocated) > > +SYM_FUNC_START_LOCAL_NOALIGN(startup32_enable_nx_if_supported) > + pushq %rbx > + > + leaq has_nx(%rip), %rcx > + > + mov $0x80000001, %eax > + cpuid > + btl $20, %edx btl $(X86_FEATURE_NX & 31), %edx But also need to check for the availability of the extended leaf in the first place. > + jnc .Lnonx > + > + movl $1, (%rcx) Your pointer has been clobbered with some feature flags. movl $1, has_nx(%rip) will work fine without needing the intermediary lea. ~Andrew
