On Tue, Aug 01, 2017 at 05:08:14PM -0700, Nadav Amit wrote: > While deferring TLB flushes is a good practice, the reverted patch > caused pending TLB flushes to be checked while the page-table lock is > not taken. As a result, in architectures with weak memory model (PPC), > Linux may miss a memory-barrier, miss the fact TLB flushes are pending, > and cause (in theory) a memory corruption. > > Since the alternative of using smp_mb__after_unlock_lock() was > considered a bit open-coded, and the performance impact is expected to > be small, the previous patch is reverted. FWIW this Changelog sucks arse; you completely fail to explain the broken ordering. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>
