On Fri 12-02-21 12:22:07, Matthew Wilcox wrote: > On Fri, Feb 12, 2021 at 08:18:11PM +0900, Tetsuo Handa wrote: > > On 2021/02/12 1:41, Michal Hocko wrote: > > > But I suspect we have drifted away from the original issue. I thought > > > that a simple check would help us narrow down this particular case and > > > somebody messing up from the IRQ context didn't sound like a completely > > > off. > > > > > > > From my experience at https://lkml.kernel.org/r/201409192053.IHJ35462.JLOMOSOFFVtQFH@xxxxxxxxxxxxxxxxxxx , > > I think we can replace direct PF_* manipulation with macros which do not receive "struct task_struct *" argument. > > Since TASK_PFA_TEST()/TASK_PFA_SET()/TASK_PFA_CLEAR() are for manipulating PFA_* flags on a remote thread, we can > > define similar ones for manipulating PF_* flags on current thread. Then, auditing dangerous users becomes easier. > > No, nobody is manipulating another task's GFP flags. Agreed. And nobody should be manipulating PF flags on remote tasks either. -- Michal Hocko SUSE Labs
