On Sat, 29 Jun 2024 10:09:46 +0800 Miaohe Lin <linmiaohe@xxxxxxxxxx> wrote: > On 2024/6/25 10:23, Rui Qi wrote: > > From: Rui Qi <qirui.001@xxxxxxxxxxxxx> > > > > we hope that memory errors can be successfully handled quickly, using > > __GFP_MEMALLOC can help us improve the success rate of processing > > Comments of __GFP_MEMALLOC says: > > * Users of this flag have to be extremely careful to not deplete the reserve > * completely and implement a throttling mechanism which controls the > * consumption of the reserve based on the amount of freed memory. > > It seems there's no such throttling mechanism in memory_failure. > > > under memory pressure, because to_kill struct is freed very quickly, > > so using __GFP_MEMALLOC will not exacerbate memory pressure for a long time, > > and more memory will be freed after killed task exiting, which will also > > Tasks might not be killed even to_kill struct is allocated. > > ... > > > - raw_hwp = kmalloc(sizeof(struct raw_hwp_page), GFP_ATOMIC); > > + raw_hwp = kmalloc(sizeof(struct raw_hwp_page), GFP_ATOMIC | __GFP_MEMALLOC); > > In already hardware poisoned code path, raw_hwp can be allocated to store raw page info > without killing anything. So __GFP_MEMALLOC might not be suitable to use. > Or am I miss something? Yes, I'm doubtful about this patch. I think that rather than poking at a particular implementation, it would be helpful for us to see a complete description of the issues which were observed, please. Let's see the bug report and we can discuss fixes later.
