Re: [PATCH] hv_balloon: avoid touching uninitialized struct page during tail onlining

2019-01-08 Thread Sasha Levin
On Mon, Jan 07, 2019 at 07:38:20PM +0100, Vitaly Kuznetsov wrote: Sasha Levin writes: On Mon, Jan 07, 2019 at 02:44:30PM +0100, Vitaly Kuznetsov wrote: P.S. I still think about bringing mem_hotplug_begin()/done() to hv_balloon but that's going to be a separate discussion, here I want to have

Re: [PATCH] hv_balloon: avoid touching uninitialized struct page during tail onlining

2019-01-08 Thread Vitaly Kuznetsov
Dan Carpenter writes: > On Mon, Jan 07, 2019 at 07:38:20PM +0100, Vitaly Kuznetsov wrote: >> (I remember Greg disliked when people were tagging patches for stable@ >> themselves, he prefered maintainers deciding if the particular commit >> deserves stable@ or not - but as you have a tree now we

Re: [PATCH] hv_balloon: avoid touching uninitialized struct page during tail onlining

2019-01-08 Thread Dan Carpenter
On Mon, Jan 07, 2019 at 07:38:20PM +0100, Vitaly Kuznetsov wrote: > (I remember Greg disliked when people were tagging patches for stable@ > themselves, he prefered maintainers deciding if the particular commit > deserves stable@ or not - but as you have a tree now we may as well have > different

Re: [PATCH] hv_balloon: avoid touching uninitialized struct page during tail onlining

2019-01-08 Thread Vitaly Kuznetsov
David Hildenbrand writes: > On 07.01.19 14:44, Vitaly Kuznetsov wrote: >> David Hildenbrand writes: >> ... >>> On 04.01.19 15:19, Vitaly Kuznetsov wrote: if (start_pfn > has->start_pfn && - !PageReserved(pfn_to_page(start_pfn - 1))) +

Re: [PATCH] hv_balloon: avoid touching uninitialized struct page during tail onlining

2019-01-08 Thread David Hildenbrand
On 07.01.19 14:44, Vitaly Kuznetsov wrote: > David Hildenbrand writes: > >> On 04.01.19 15:19, Vitaly Kuznetsov wrote: >>> Hyper-V memory hotplug protocol has 2M granularity and in Linux x86 we use >>> 128M. To deal with it we implement partial section onlining by registering >>> custom page

Re: [PATCH] hv_balloon: avoid touching uninitialized struct page during tail onlining

2019-01-07 Thread Greg KH
On Mon, Jan 07, 2019 at 07:38:20PM +0100, Vitaly Kuznetsov wrote: > (I remember Greg disliked when people were tagging patches for stable@ > themselves, he prefered maintainers deciding if the particular commit > deserves stable@ or not - but as you have a tree now we may as well have > different

Re: [PATCH] hv_balloon: avoid touching uninitialized struct page during tail onlining

2019-01-07 Thread Vitaly Kuznetsov
Sasha Levin writes: > On Mon, Jan 07, 2019 at 02:44:30PM +0100, Vitaly Kuznetsov wrote: >>P.S. I still think about bringing mem_hotplug_begin()/done() to >>hv_balloon but that's going to be a separate discussion, here I want to >>have a small fix backportable to stable. > > This should probably

Re: [PATCH] hv_balloon: avoid touching uninitialized struct page during tail onlining

2019-01-07 Thread Sasha Levin
On Mon, Jan 07, 2019 at 02:44:30PM +0100, Vitaly Kuznetsov wrote: David Hildenbrand writes: On 04.01.19 15:19, Vitaly Kuznetsov wrote: Hyper-V memory hotplug protocol has 2M granularity and in Linux x86 we use 128M. To deal with it we implement partial section onlining by registering custom

Re: [PATCH] hv_balloon: avoid touching uninitialized struct page during tail onlining

2019-01-07 Thread Vitaly Kuznetsov
David Hildenbrand writes: > On 04.01.19 15:19, Vitaly Kuznetsov wrote: >> Hyper-V memory hotplug protocol has 2M granularity and in Linux x86 we use >> 128M. To deal with it we implement partial section onlining by registering >> custom page onlining callback (hv_online_page()). Later, when more

Re: [PATCH] hv_balloon: avoid touching uninitialized struct page during tail onlining

2019-01-07 Thread David Hildenbrand
On 04.01.19 15:19, Vitaly Kuznetsov wrote: > Hyper-V memory hotplug protocol has 2M granularity and in Linux x86 we use > 128M. To deal with it we implement partial section onlining by registering > custom page onlining callback (hv_online_page()). Later, when more memory > arrives we try to

[PATCH] hv_balloon: avoid touching uninitialized struct page during tail onlining

2019-01-04 Thread Vitaly Kuznetsov
Hyper-V memory hotplug protocol has 2M granularity and in Linux x86 we use 128M. To deal with it we implement partial section onlining by registering custom page onlining callback (hv_online_page()). Later, when more memory arrives we try to online the 'tail' (see hv_bring_pgs_online()). It was