On Tue, Dec 7, 2021 at 2:47 PM Suren Baghdasaryan <surenb@xxxxxxxxxx> wrote: > > On Tue, Dec 7, 2021 at 2:07 PM Matthew Wilcox <willy@xxxxxxxxxxxxx> wrote: > > > > On Tue, Dec 07, 2021 at 01:50:30PM -0800, Suren Baghdasaryan wrote: > > > - Added a comment for vm_operations_struct::close, documenting restriction for > > > taking mmap_lock in the callback, per Michal Hocko and Matthew Wilcox > > > > This should be a separate patch because it stands alone, but ... > > I thought about it and since it was relevant to the change in > remove_vma locking, I thought it would fit here. However, if you > insist on splitting it, I'll post it as a separate patch. Please let > me know. > > > > > > struct vm_operations_struct { > > > void (*open)(struct vm_area_struct * area); > > > + /* > > > + * Called with mmap_lock lock held for write from __split_vma and > > > + * remove_vma, therefore should never take that lock. > > > + */ > > > > Your whitespace indentation is weird. And it'd be nice to make this a > > kernel-doc comment (I know none of the others are, but that should be > > fixed too). And naming the functions that call it is wrong too. > > > > /** > > * @close: Called when the VMA is being removed from the MM. > > * Context: Caller holds mmap_lock. BTW, is the caller always required to hold mmap_lock for write or it *might* hold it? > > */ > > Ack. Will change and include in the next respin once I hear from you > on the preference for a separate patch. > Thanks!