[PATCH] mm/slub: fix panic in slab_alloc_node()

2020-10-27 Thread Laurent Dufour
While doing memory hot-unplug operation on a PowerPC VM running 1024 CPUs with 11TB of ram, I hit the following panic: BUG: Kernel NULL pointer dereference on read at 0x0007 Faulting instruction address: 0xc0456048 Oops: Kernel access of bad area, sig: 11 [#2] LE PAGE_SIZE=64K

Re: [PATCH] mm/slub: fix panic in slab_alloc_node()

2020-10-27 Thread Michal Hocko
[Cc Vlastimil] On Tue 27-10-20 15:09:26, Laurent Dufour wrote: > While doing memory hot-unplug operation on a PowerPC VM running 1024 CPUs > with 11TB of ram, I hit the following panic: > > BUG: Kernel NULL pointer dereference on read at 0x0007 > Faulting instruction address:

Re: [PATCH] mm/slub: fix panic in slab_alloc_node()

2020-10-27 Thread Michal Hocko
On Tue 27-10-20 15:39:46, Laurent Dufour wrote: > Le 27/10/2020 à 15:24, Michal Hocko a écrit : > > [Cc Vlastimil] > > > > On Tue 27-10-20 15:09:26, Laurent Dufour wrote: > > > While doing memory hot-unplug operation on a PowerPC VM running 1024 CPUs > > > with 11TB of ram, I hit the following

Re: [PATCH] mm/slub: fix panic in slab_alloc_node()

2020-10-27 Thread Vlastimil Babka
On 10/27/20 4:12 PM, Laurent Dufour wrote: Le 27/10/2020 à 16:03, Michal Hocko a écrit : On Tue 27-10-20 15:39:46, Laurent Dufour wrote: Le 27/10/2020 à 15:24, Michal Hocko a écrit : [Cc Vlastimil] On Tue 27-10-20 15:09:26, Laurent Dufour wrote: Could you be more specific? I am especially

Re: [PATCH] mm/slub: fix panic in slab_alloc_node()

2020-10-27 Thread Laurent Dufour
Le 27/10/2020 à 16:03, Michal Hocko a écrit : On Tue 27-10-20 15:39:46, Laurent Dufour wrote: Le 27/10/2020 à 15:24, Michal Hocko a écrit : [Cc Vlastimil] On Tue 27-10-20 15:09:26, Laurent Dufour wrote: While doing memory hot-unplug operation on a PowerPC VM running 1024 CPUs with 11TB of

Re: [PATCH] mm/slub: fix panic in slab_alloc_node()

2020-10-27 Thread Laurent Dufour
Le 27/10/2020 à 15:24, Michal Hocko a écrit : [Cc Vlastimil] On Tue 27-10-20 15:09:26, Laurent Dufour wrote: While doing memory hot-unplug operation on a PowerPC VM running 1024 CPUs with 11TB of ram, I hit the following panic: BUG: Kernel NULL pointer dereference on read at 0x0007