On Mon, Mar 23, 2020 at 08:18:04PM +0100, Jann Horn wrote: > On Wed, Mar 18, 2020 at 9:54 PM Sasha Levin <sashal@xxxxxxxxxx> wrote: > > > > From: Peter Zijlstra <peterz@xxxxxxxxxxxxx> > > > > [ Upstream commit 8019ad13ef7f64be44d4f892af9c840179009254 ] > > > > As reported by Jann, ihold() does not in fact guarantee inode > > persistence. And instead of making it so, replace the usage of inode > > pointers with a per boot, machine wide, unique inode identifier. > > > > This sequence number is global, but shared (file backed) futexes are > > rare enough that this should not become a performance issue. > > Please also take this patch, together with > 8d67743653dce5a0e7aa500fcccb237cde7ad88e "futex: Unbreak futex > hashing", into the older stable branches. This has to go all the way > back; as far as I can tell, the bug already existed at the beginning > of git history. I have queued these up now, thanks for the hint. greg k-h
