Re: [PATCH 2/3] powerpc/mm: Rename find_linux_pte_or_hugepte

["Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>]

Benjamin Herrenschmidt <benh@kernel.crashing.org> writes:

> On Tue, 2017-05-16 at 14:56 +0530, Aneesh Kumar K.V wrote:
>> +static inline pte_t *find_linux_pte(pgd_t *pgdir, unsigned long ea,
>> +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=
=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 bool *is_thp, =
unsigned *hshift)
>> +{
>> +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0VM_WARN((!arch_irqs_disabled(=
) && !__hard_irqs_disabled()) ,
>> +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=
=A0=C2=A0=C2=A0=C2=A0"%s called with irq enabled\n", __func__);
>> +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0return __find_linux_pte(pgdir=
, ea, is_thp, hshift);
>> +}
>> +
>
> When is arch_irqs_disabled() not sufficient ?

We can do lockless page table walk in interrupt handlers where we find
MSR_EE =3D 0. I was not sure we mark softenabled 0 there. What I wanted to
indicate in the patch is that we are safe with either softenable =3D 0 or M=
SR_EE =3D 0

-aneesh