Re: [PATCH -next v2] mm/hotplug: fix a null-ptr-deref during NUMA boot

2019-06-26 Thread Pingfan Liu
On Wed, Jun 26, 2019 at 9:57 PM Michal Hocko wrote: > > On Mon 24-06-19 16:42:20, Pingfan Liu wrote: > > Hi Michal, > > > > What about dropping the change of the online definition of your patch, > > just do the following? > > I am sorry but I am unlikely to find some more time to look into this.

Re: [PATCH -next v2] mm/hotplug: fix a null-ptr-deref during NUMA boot

2019-06-26 Thread Michal Hocko
On Mon 24-06-19 16:42:20, Pingfan Liu wrote: > Hi Michal, > > What about dropping the change of the online definition of your patch, > just do the following? I am sorry but I am unlikely to find some more time to look into this. I am willing to help reviewing but I will not find enough time to

Re: [PATCH -next v2] mm/hotplug: fix a null-ptr-deref during NUMA boot

2019-06-24 Thread Pingfan Liu
Hi Michal, What about dropping the change of the online definition of your patch, just do the following? diff --git a/arch/x86/mm/numa.c b/arch/x86/mm/numa.c index e6dad60..9c087c3 100644 --- a/arch/x86/mm/numa.c +++ b/arch/x86/mm/numa.c @@ -749,13 +749,12 @@ static void __init

Re: [PATCH -next v2] mm/hotplug: fix a null-ptr-deref during NUMA boot

2019-06-21 Thread Michal Hocko
On Fri 21-06-19 09:17:58, Qian Cai wrote: > Sigh... > > I don't see any benefit to keep the broken commit, > > "x86, numa: always initialize all possible nodes" > > for so long in linux-next that just prevent x86 NUMA machines with any memory- > less node from booting. > > Andrew, maybe it is

Re: [PATCH -next v2] mm/hotplug: fix a null-ptr-deref during NUMA boot

2019-06-21 Thread Qian Cai
Sigh... I don't see any benefit to keep the broken commit, "x86, numa: always initialize all possible nodes" for so long in linux-next that just prevent x86 NUMA machines with any memory- less node from booting. Andrew, maybe it is time to drop this patch until Michal found some time to fix it

Re: [PATCH -next v2] mm/hotplug: fix a null-ptr-deref during NUMA boot

2019-06-02 Thread Pingfan Liu
On Fri, May 31, 2019 at 5:03 PM Michal Hocko wrote: > > On Thu 30-05-19 20:55:32, Pingfan Liu wrote: > > On Wed, May 29, 2019 at 2:20 AM Michal Hocko wrote: > > > > > > [Sorry for a late reply] > > > > > > On Thu 23-05-19 11:58:45, Pingfan Liu wrote: > > > > On Wed, May 22, 2019 at 7:16 PM

Re: [PATCH -next v2] mm/hotplug: fix a null-ptr-deref during NUMA boot

2019-05-31 Thread Michal Hocko
On Thu 30-05-19 20:55:32, Pingfan Liu wrote: > On Wed, May 29, 2019 at 2:20 AM Michal Hocko wrote: > > > > [Sorry for a late reply] > > > > On Thu 23-05-19 11:58:45, Pingfan Liu wrote: > > > On Wed, May 22, 2019 at 7:16 PM Michal Hocko wrote: > > > > > > > > On Wed 22-05-19 15:12:16, Pingfan Liu

Re: [PATCH -next v2] mm/hotplug: fix a null-ptr-deref during NUMA boot

2019-05-30 Thread Pingfan Liu
On Wed, May 29, 2019 at 2:21 AM Michal Hocko wrote: > > On Thu 23-05-19 12:00:46, Pingfan Liu wrote: > [...] > > > Yes, but maybe it will pay great effort on it. > > > > > And as a first step, we can find a way to fix the bug reported by me > > and the one reported by Barret > > Can we try

Re: [PATCH -next v2] mm/hotplug: fix a null-ptr-deref during NUMA boot

2019-05-30 Thread Pingfan Liu
On Wed, May 29, 2019 at 2:20 AM Michal Hocko wrote: > > [Sorry for a late reply] > > On Thu 23-05-19 11:58:45, Pingfan Liu wrote: > > On Wed, May 22, 2019 at 7:16 PM Michal Hocko wrote: > > > > > > On Wed 22-05-19 15:12:16, Pingfan Liu wrote: > [...] > > > > But in fact, we already have

Re: [PATCH -next v2] mm/hotplug: fix a null-ptr-deref during NUMA boot

2019-05-28 Thread Michal Hocko
On Thu 23-05-19 12:00:46, Pingfan Liu wrote: [...] > > Yes, but maybe it will pay great effort on it. > > > And as a first step, we can find a way to fix the bug reported by me > and the one reported by Barret Can we try http://lkml.kernel.org/r/20190513140448.gj24...@dhcp22.suse.cz for starter?

Re: [PATCH -next v2] mm/hotplug: fix a null-ptr-deref during NUMA boot

2019-05-28 Thread Michal Hocko
[Sorry for a late reply] On Thu 23-05-19 11:58:45, Pingfan Liu wrote: > On Wed, May 22, 2019 at 7:16 PM Michal Hocko wrote: > > > > On Wed 22-05-19 15:12:16, Pingfan Liu wrote: [...] > > > But in fact, we already have for_each_node_state(nid, N_MEMORY) to > > > cover this purpose. > > > > I do

Re: [PATCH -next v2] mm/hotplug: fix a null-ptr-deref during NUMA boot

2019-05-22 Thread Pingfan Liu
On Thu, May 23, 2019 at 11:58 AM Pingfan Liu wrote: > > On Wed, May 22, 2019 at 7:16 PM Michal Hocko wrote: > > > > On Wed 22-05-19 15:12:16, Pingfan Liu wrote: > > > On Mon, May 13, 2019 at 11:31 PM Michal Hocko wrote: > > > > > > > > On Mon 13-05-19 11:20:46, Qian Cai wrote: > > > > > On Mon,

Re: [PATCH -next v2] mm/hotplug: fix a null-ptr-deref during NUMA boot

2019-05-22 Thread Pingfan Liu
On Wed, May 22, 2019 at 7:16 PM Michal Hocko wrote: > > On Wed 22-05-19 15:12:16, Pingfan Liu wrote: > > On Mon, May 13, 2019 at 11:31 PM Michal Hocko wrote: > > > > > > On Mon 13-05-19 11:20:46, Qian Cai wrote: > > > > On Mon, 2019-05-13 at 16:04 +0200, Michal Hocko wrote: > > > > > On Mon

Re: [PATCH -next v2] mm/hotplug: fix a null-ptr-deref during NUMA boot

2019-05-22 Thread Michal Hocko
On Wed 22-05-19 15:12:16, Pingfan Liu wrote: > On Mon, May 13, 2019 at 11:31 PM Michal Hocko wrote: > > > > On Mon 13-05-19 11:20:46, Qian Cai wrote: > > > On Mon, 2019-05-13 at 16:04 +0200, Michal Hocko wrote: > > > > On Mon 13-05-19 09:43:59, Qian Cai wrote: > > > > > On Mon, 2019-05-13 at

Re: [PATCH -next v2] mm/hotplug: fix a null-ptr-deref during NUMA boot

2019-05-22 Thread Pingfan Liu
On Mon, May 13, 2019 at 11:31 PM Michal Hocko wrote: > > On Mon 13-05-19 11:20:46, Qian Cai wrote: > > On Mon, 2019-05-13 at 16:04 +0200, Michal Hocko wrote: > > > On Mon 13-05-19 09:43:59, Qian Cai wrote: > > > > On Mon, 2019-05-13 at 14:41 +0200, Michal Hocko wrote: > > > > > On Sun 12-05-19

Re: [PATCH -next v2] mm/hotplug: fix a null-ptr-deref during NUMA boot

2019-05-13 Thread Michal Hocko
On Mon 13-05-19 11:20:46, Qian Cai wrote: > On Mon, 2019-05-13 at 16:04 +0200, Michal Hocko wrote: > > On Mon 13-05-19 09:43:59, Qian Cai wrote: > > > On Mon, 2019-05-13 at 14:41 +0200, Michal Hocko wrote: > > > > On Sun 12-05-19 01:48:29, Qian Cai wrote: > > > > > The linux-next commit ("x86,

Re: [PATCH -next v2] mm/hotplug: fix a null-ptr-deref during NUMA boot

2019-05-13 Thread Qian Cai
On Mon, 2019-05-13 at 16:04 +0200, Michal Hocko wrote: > On Mon 13-05-19 09:43:59, Qian Cai wrote: > > On Mon, 2019-05-13 at 14:41 +0200, Michal Hocko wrote: > > > On Sun 12-05-19 01:48:29, Qian Cai wrote: > > > > The linux-next commit ("x86, numa: always initialize all possible > > > > nodes")

Re: [PATCH -next v2] mm/hotplug: fix a null-ptr-deref during NUMA boot

2019-05-13 Thread Michal Hocko
On Mon 13-05-19 09:43:59, Qian Cai wrote: > On Mon, 2019-05-13 at 14:41 +0200, Michal Hocko wrote: > > On Sun 12-05-19 01:48:29, Qian Cai wrote: > > > The linux-next commit ("x86, numa: always initialize all possible > > > nodes") introduced a crash below during boot for systems with a > > >

Re: [PATCH -next v2] mm/hotplug: fix a null-ptr-deref during NUMA boot

2019-05-13 Thread Qian Cai
On Mon, 2019-05-13 at 14:41 +0200, Michal Hocko wrote: > On Sun 12-05-19 01:48:29, Qian Cai wrote: > > The linux-next commit ("x86, numa: always initialize all possible > > nodes") introduced a crash below during boot for systems with a > > memory-less node. This is due to CPUs that get onlined

Re: [PATCH -next v2] mm/hotplug: fix a null-ptr-deref during NUMA boot

2019-05-13 Thread Michal Hocko
On Sun 12-05-19 01:48:29, Qian Cai wrote: > The linux-next commit ("x86, numa: always initialize all possible > nodes") introduced a crash below during boot for systems with a > memory-less node. This is due to CPUs that get onlined during SMP boot, > but that onlining triggers a page fault in

[PATCH -next v2] mm/hotplug: fix a null-ptr-deref during NUMA boot

2019-05-11 Thread Qian Cai
The linux-next commit ("x86, numa: always initialize all possible nodes") introduced a crash below during boot for systems with a memory-less node. This is due to CPUs that get onlined during SMP boot, but that onlining triggers a page fault in bus_add_device() during device registration: