| Message ID | 20180522100756.18478-3-david@redhat.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 05/22/2018 01:07 PM, David Hildenbrand wrote: > Using module_init() is wrong. E.g. ACPI adds and onlines memory before > our memory notifier gets registered. > > This makes sure that ACPI memory detected during boot up will not > result in a kernel crash. > > Easily reproducable with QEMU, just specify a DIMM when starting up. reproducible > > Signed-off-by: David Hildenbrand <david@redhat.com> > --- Fixes: fa69b5989bb0 ("mm/kasan: add support for memory hotplug") Acked-by: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: <stable@vger.kernel.org> > mm/kasan/kasan.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/mm/kasan/kasan.c b/mm/kasan/kasan.c > index 53564229674b..a8b85706e2d6 100644 > --- a/mm/kasan/kasan.c > +++ b/mm/kasan/kasan.c > @@ -892,5 +892,5 @@ static int __init kasan_memhotplug_init(void) > return 0; > } > > -module_init(kasan_memhotplug_init); > +core_initcall(kasan_memhotplug_init); > #endif >
On 22.05.2018 18:26, Andrey Ryabinin wrote: > > > On 05/22/2018 01:07 PM, David Hildenbrand wrote: >> Using module_init() is wrong. E.g. ACPI adds and onlines memory before >> our memory notifier gets registered. >> >> This makes sure that ACPI memory detected during boot up will not >> result in a kernel crash. >> >> Easily reproducable with QEMU, just specify a DIMM when starting up. > > reproducible >> >> Signed-off-by: David Hildenbrand <david@redhat.com> >> --- > > Fixes: fa69b5989bb0 ("mm/kasan: add support for memory hotplug") > Acked-by: Andrey Ryabinin <aryabinin@virtuozzo.com> > Cc: <stable@vger.kernel.org> Think this even dates back to: 786a8959912e ("kasan: disable memory hotplug") > >> mm/kasan/kasan.c | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >> diff --git a/mm/kasan/kasan.c b/mm/kasan/kasan.c >> index 53564229674b..a8b85706e2d6 100644 >> --- a/mm/kasan/kasan.c >> +++ b/mm/kasan/kasan.c >> @@ -892,5 +892,5 @@ static int __init kasan_memhotplug_init(void) >> return 0; >> } >> >> -module_init(kasan_memhotplug_init); >> +core_initcall(kasan_memhotplug_init); >> #endif >>
On 05/22/2018 07:36 PM, David Hildenbrand wrote: > On 22.05.2018 18:26, Andrey Ryabinin wrote: >> >> >> On 05/22/2018 01:07 PM, David Hildenbrand wrote: >>> Using module_init() is wrong. E.g. ACPI adds and onlines memory before >>> our memory notifier gets registered. >>> >>> This makes sure that ACPI memory detected during boot up will not >>> result in a kernel crash. >>> >>> Easily reproducable with QEMU, just specify a DIMM when starting up. >> >> reproducible >>> >>> Signed-off-by: David Hildenbrand <david@redhat.com> >>> --- >> >> Fixes: fa69b5989bb0 ("mm/kasan: add support for memory hotplug") >> Acked-by: Andrey Ryabinin <aryabinin@virtuozzo.com> >> Cc: <stable@vger.kernel.org> > > Think this even dates back to: > > 786a8959912e ("kasan: disable memory hotplug") > Indeed.
On Tue, 22 May 2018 22:50:12 +0300 Andrey Ryabinin <aryabinin@virtuozzo.com> wrote: > > > On 05/22/2018 07:36 PM, David Hildenbrand wrote: > > On 22.05.2018 18:26, Andrey Ryabinin wrote: > >> > >> > >> On 05/22/2018 01:07 PM, David Hildenbrand wrote: > >>> Using module_init() is wrong. E.g. ACPI adds and onlines memory before > >>> our memory notifier gets registered. > >>> > >>> This makes sure that ACPI memory detected during boot up will not > >>> result in a kernel crash. > >>> > >>> Easily reproducable with QEMU, just specify a DIMM when starting up. > >> > >> reproducible > >>> > >>> Signed-off-by: David Hildenbrand <david@redhat.com> > >>> --- > >> > >> Fixes: fa69b5989bb0 ("mm/kasan: add support for memory hotplug") > >> Acked-by: Andrey Ryabinin <aryabinin@virtuozzo.com> > >> Cc: <stable@vger.kernel.org> > > > > Think this even dates back to: > > > > 786a8959912e ("kasan: disable memory hotplug") > > > > Indeed. Is a backport to -stable justified for either of these patches?
On 05/23/2018 12:07 AM, Andrew Morton wrote: > On Tue, 22 May 2018 22:50:12 +0300 Andrey Ryabinin <aryabinin@virtuozzo.com> wrote: > >> >> >> On 05/22/2018 07:36 PM, David Hildenbrand wrote: >>> On 22.05.2018 18:26, Andrey Ryabinin wrote: >>>> >>>> >>>> On 05/22/2018 01:07 PM, David Hildenbrand wrote: >>>>> Using module_init() is wrong. E.g. ACPI adds and onlines memory before >>>>> our memory notifier gets registered. >>>>> >>>>> This makes sure that ACPI memory detected during boot up will not >>>>> result in a kernel crash. >>>>> >>>>> Easily reproducable with QEMU, just specify a DIMM when starting up. >>>> >>>> reproducible >>>>> >>>>> Signed-off-by: David Hildenbrand <david@redhat.com> >>>>> --- >>>> >>>> Fixes: fa69b5989bb0 ("mm/kasan: add support for memory hotplug") >>>> Acked-by: Andrey Ryabinin <aryabinin@virtuozzo.com> >>>> Cc: <stable@vger.kernel.org> >>> >>> Think this even dates back to: >>> >>> 786a8959912e ("kasan: disable memory hotplug") >>> >> >> Indeed. > > Is a backport to -stable justified for either of these patches? > I don't see any reasons to not backport these. The first one fixes failure to online memory, why it shouldn't be fixed in -stable? The second one is fixes boot crash, it's definitely stable material IMO.
On 23.05.2018 11:59, Andrey Ryabinin wrote: > > > On 05/23/2018 12:07 AM, Andrew Morton wrote: >> On Tue, 22 May 2018 22:50:12 +0300 Andrey Ryabinin <aryabinin@virtuozzo.com> wrote: >> >>> >>> >>> On 05/22/2018 07:36 PM, David Hildenbrand wrote: >>>> On 22.05.2018 18:26, Andrey Ryabinin wrote: >>>>> >>>>> >>>>> On 05/22/2018 01:07 PM, David Hildenbrand wrote: >>>>>> Using module_init() is wrong. E.g. ACPI adds and onlines memory before >>>>>> our memory notifier gets registered. >>>>>> >>>>>> This makes sure that ACPI memory detected during boot up will not >>>>>> result in a kernel crash. >>>>>> >>>>>> Easily reproducable with QEMU, just specify a DIMM when starting up. >>>>> >>>>> reproducible >>>>>> >>>>>> Signed-off-by: David Hildenbrand <david@redhat.com> >>>>>> --- >>>>> >>>>> Fixes: fa69b5989bb0 ("mm/kasan: add support for memory hotplug") >>>>> Acked-by: Andrey Ryabinin <aryabinin@virtuozzo.com> >>>>> Cc: <stable@vger.kernel.org> >>>> >>>> Think this even dates back to: >>>> >>>> 786a8959912e ("kasan: disable memory hotplug") >>>> >>> >>> Indeed. >> >> Is a backport to -stable justified for either of these patches? >> > > I don't see any reasons to not backport these. > The first one fixes failure to online memory, why it shouldn't be fixed in -stable? > The second one is fixes boot crash, it's definitely stable material IMO. > Agreed, at least the second one should be cc stable, as I can reproduce it with a simple QEMU command.
diff --git a/mm/kasan/kasan.c b/mm/kasan/kasan.c index 53564229674b..a8b85706e2d6 100644 --- a/mm/kasan/kasan.c +++ b/mm/kasan/kasan.c @@ -892,5 +892,5 @@ static int __init kasan_memhotplug_init(void) return 0; } -module_init(kasan_memhotplug_init); +core_initcall(kasan_memhotplug_init); #endif
Using module_init() is wrong. E.g. ACPI adds and onlines memory before our memory notifier gets registered. This makes sure that ACPI memory detected during boot up will not result in a kernel crash. Easily reproducable with QEMU, just specify a DIMM when starting up. Signed-off-by: David Hildenbrand <david@redhat.com> --- mm/kasan/kasan.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)