RE: [PATCH 6/7] KVM: VMX: Provide separate subroutines for invoking NMI vs. IRQ handlers

Li, Xin3
2022-12-14T21:23:39Z

> +
> + /*
> + * "Restore" RSP from RBP, even though IRET has already unwound
> RSP to
> + * the correct value. objtool doesn't know the callee will IRET and,
> + * without the explicit restore, thinks the stack is getting walloped.
> + * Using an unwind hint is problematic due to x86-64's dynamic
> alignment.
> + */
> + mov %_ASM_BP, %_ASM_SP
> + pop %_ASM_BP
> + RET

For NMI, after this RET instruction, we continue to block NMIs. IRET instead?

> +.endm
> +
> .section .noinstr.text, "ax"