Pull futex fix from Thomas Gleixner:
"Fix for yet another subtle futex issue.
The futex code used ihold() to prevent inodes from vanishing, but
ihold() does not guarantee inode persistence. Replace the inode
pointer with a per boot, machine wide, unique inode identifier.
The second commit fixes the breakage of the hash mechanism which
causes a 100% performance regression"
* tag 'locking-urgent-2020-03-15' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
futex: Unbreak futex hashing
futex: Fix inode life-time issue