On Tue 15-02-22 10:10:53, Suren Baghdasaryan wrote: > On Tue, Feb 15, 2022 at 9:53 AM Yang Shi <shy828301@xxxxxxxxx> wrote: [...] > > Isn't the below race possible? > > > > CPU A CPU B > > exiting: > > mmap_write_lock > > remove_vma() > > mmap_write_unlock > > process_mrelease: > > mmap_read_lock > > __oom_reap_task_mm > > mmap_read_unlock > > > > Sure, that sequence (would not call it a race) is possible but in this > case __oom_reap_task_mm will find no vmas in the mm because exit_mmap > freed and removed all of them. I didn't really have chance to have a closer look but I do not see exit_mmap doing mm->mmap = NULL so the pointer can be a freed vma unless I am missing something. I thought we've had it in your patches? Has this got lost somewhere in the process? -- Michal Hocko SUSE Labs
