On Tue, Feb 20, 2024 at 05:23:29PM +0100, Michal Hocko wrote: > On Mon 19-02-24 09:17:36, Suren Baghdasaryan wrote: > [...] > > For now I think with Vlastimil's __GFP_NOWARN suggestion the code > > becomes safe and the only risk is to lose this report. If we get cases > > with reports missing this data, we can easily change to reserved > > memory. > > This is not just about missing part of the oom report. This is annoying > but not earth shattering. Eating into very small reserves (that might be > the only usable memory while the system is struggling in OOM situation) > could cause functional problems that would be non trivial to test for. > All that for debugging purposes is just lame. If you want to reuse the code > for a different purpose then abstract it and allocate the buffer when you > can afford that and use preallocated on when in OOM situation. > > We have always went extra mile to avoid potentially disruptive > operations from the oom handling code and I do not see any good reason > to diverge from that principle. Michal, I gave you the logic between dedicated reserves and system reserves. Please stop repeating these vague what-ifs.