Re: [PATCH] mm/mincore: handle non-swap entries before !CONFIG_SWAP guard

Re: [PATCH] mm/mincore: handle non-swap entries before !CONFIG_SWAP guard

[Usama Arif]

On 02/06/2026 18:51, Pedro Falcato wrote:
> On Tue, Jun 02, 2026 at 10:22:47AM -0700, Usama Arif wrote:
>> mincore_swap() also fields migration/hwpoison entries (and shmem
>> swapin-error entries), which can exist on !CONFIG_SWAP builds when
>> CONFIG_MIGRATION or CONFIG_MEMORY_FAILURE is enabled.  The
>> !IS_ENABLED(CONFIG_SWAP) guard ran before the non-swap-entry early
>> return, so mincore_pte_range() can spuriously WARN and report these
>> pages nonresident on !CONFIG_SWAP kernels.
>>
>> Move the guard below the non-swap-entry check so only true swap
>> entries trip the WARN, and migration/hwpoison entries take the
>> existing "uptodate / non-shmem" path.
>>
>> Fixes: 1f2052755c15 ("mm/mincore: use a helper for checking the swap cache")
>> Signed-off-by: Usama Arif <usama.arif@linux.dev>
> 
> LGTM, thanks!
> 
> Reviewed-by: Pedro Falcato <pfalcato@suse.de>
> 
> Maybe Cc: stable@kernel.org ?
> 

Ah yes, I have cc-ed stable in the reply to this email, but probably that
is not enough?

Thanks

Re: [PATCH] mm/mincore: handle non-swap entries before !CONFIG_SWAP guard

[Lorenzo Stoakes]

On Wed, Jun 03, 2026 at 10:52:24AM +0100, Usama Arif wrote:
>
>
> On 02/06/2026 18:51, Pedro Falcato wrote:
> > On Tue, Jun 02, 2026 at 10:22:47AM -0700, Usama Arif wrote:
> >> mincore_swap() also fields migration/hwpoison entries (and shmem
> >> swapin-error entries), which can exist on !CONFIG_SWAP builds when
> >> CONFIG_MIGRATION or CONFIG_MEMORY_FAILURE is enabled.  The
> >> !IS_ENABLED(CONFIG_SWAP) guard ran before the non-swap-entry early
> >> return, so mincore_pte_range() can spuriously WARN and report these
> >> pages nonresident on !CONFIG_SWAP kernels.
> >>
> >> Move the guard below the non-swap-entry check so only true swap
> >> entries trip the WARN, and migration/hwpoison entries take the
> >> existing "uptodate / non-shmem" path.
> >>
> >> Fixes: 1f2052755c15 ("mm/mincore: use a helper for checking the swap cache")
> >> Signed-off-by: Usama Arif <usama.arif@linux.dev>
> >
> > LGTM, thanks!
> >
> > Reviewed-by: Pedro Falcato <pfalcato@suse.de>
> >
> > Maybe Cc: stable@kernel.org ?
> >
>
> Ah yes, I have cc-ed stable in the reply to this email, but probably that
> is not enough?

Yeah I think a Cc: in the body is required, but then again Andrew does add Cc's
for Cc'd parties so maybe it'll be automagically sorted out.

Andrew - probably we're good here but just checking to be sure?

>
> Thanks

Thanks, Lorenzo

Re: [PATCH] mm/mincore: handle non-swap entries before !CONFIG_SWAP guard

[Andrew Morton]

On Wed, 3 Jun 2026 13:07:04 +0100 Lorenzo Stoakes <ljs@kernel.org> wrote:

> > >> Fixes: 1f2052755c15 ("mm/mincore: use a helper for checking the swap cache")
> > >> Signed-off-by: Usama Arif <usama.arif@linux.dev>
> > >
> > > LGTM, thanks!
> > >
> > > Reviewed-by: Pedro Falcato <pfalcato@suse.de>
> > >
> > > Maybe Cc: stable@kernel.org ?
> > >
> >
> > Ah yes, I have cc-ed stable in the reply to this email, but probably that
> > is not enough?
> 
> Yeah I think a Cc: in the body is required,

It's required for MM patches because we've asked the -stable
maintainers to not auto-pick everything which has a Fixes:.

> but then again Andrew does add Cc's
> for Cc'd parties so maybe it'll be automagically sorted out.

cc:stable management is all manual here.

> Andrew - probably we're good here but just checking to be sure?

Yep, I'd added it thanks.  But please always do check!