RE: [RFC PATCH 4/9] mm: Introduce vm_ops->mprotect()

[Xing, Cedric]

> From: Christopherson, Sean J
> Sent: Friday, May 31, 2019 4:32 PM
> 
> diff --git a/include/linux/mm.h b/include/linux/mm.h index 0e8834ac32b7..50a42364a885
> 100644
> --- a/include/linux/mm.h
> +++ b/include/linux/mm.h
> @@ -458,6 +458,8 @@ struct vm_operations_struct {
>  	void (*close)(struct vm_area_struct * area);
>  	int (*split)(struct vm_area_struct * area, unsigned long addr);
>  	int (*mremap)(struct vm_area_struct * area);
> +	int (*mprotect)(struct vm_area_struct * area, unsigned long start,
> +			unsigned long end, unsigned long prot);

As I commented in my reply to the cover letter, SGX driver doesn't need to intercept mprotect() if ALLOW_* flags are not spilled into it.

>  	vm_fault_t (*fault)(struct vm_fault *vmf);
>  	vm_fault_t (*huge_fault)(struct vm_fault *vmf,
>  			enum page_entry_size pe_size);