Re: zswap z3fold + memory offline = infinite loop

2020-05-20 Thread Qian Cai
On Wed, May 20, 2020 at 10:23:38AM +0200, Vitaly Wool wrote: > On Tue, May 19, 2020 at 5:50 AM Qian Cai wrote: > > > > > > > > > Removing that check in ->isolate() is not a big deal, but ->migratepage() > > > shall not allow actual migration anyway if there are mapped objects. > > > > Is that wo

Re: zswap z3fold + memory offline = infinite loop

2020-05-20 Thread Vitaly Wool
On Tue, May 19, 2020 at 5:50 AM Qian Cai wrote: > > > > > Removing that check in ->isolate() is not a big deal, but ->migratepage() > > shall not allow actual migration anyway if there are mapped objects. > > Is that worse than an endless loop here? Well, let's figure if there really has to be

Re: zswap z3fold + memory offline = infinite loop

2020-05-18 Thread Qian Cai
On Wed, May 13, 2020 at 4:28 AM Vitaly Wool wrote: > > > > On Wed, May 13, 2020, 2:36 AM Qian Cai wrote: >> >> Put zswap z3fold pages into the memory and then offline those memory would >> trigger an infinite loop here in >> >> __offline_pages() --> do_migrate_range() because there is no error h

Re: zswap z3fold + memory offline = infinite loop

2020-05-13 Thread David Hildenbrand
On 13.05.20 02:36, Qian Cai wrote: > Put zswap z3fold pages into the memory and then offline those memory would > trigger an infinite loop here in > > __offline_pages() --> do_migrate_range() because there is no error handling, That's usually not the case, that's why we - nowadays - basically ne