Re: [PATCH v12 10/11] sparc64: Add support for ADI (Application Data Integrity)

[Dave Hansen]

On 02/21/2018 09:15 AM, Khalid Aziz wrote:
> +#define arch_validate_prot(prot, addr) sparc_validate_prot(prot, addr)
> +static inline int sparc_validate_prot(unsigned long prot, unsigned long addr)
> +{
> +	if (prot & ~(PROT_READ | PROT_WRITE | PROT_EXEC | PROT_SEM | PROT_ADI))
> +		return 0;
> +	if (prot & PROT_ADI) {
> +		if (!adi_capable())
> +			return 0;
> +
> +		if (addr) {
> +			struct vm_area_struct *vma;
> +
> +			vma = find_vma(current->mm, addr);
> +			if (vma) {
> +				/* ADI can not be enabled on PFN
> +				 * mapped pages
> +				 */
> +				if (vma->vm_flags & (VM_PFNMAP | VM_MIXEDMAP))
> +					return 0;

You don't hold mmap_sem here.  How can this work?