From 0d675523fae75f7435886bc7601ef7caed2446aa Mon Sep 17 00:00:00 2001 From: "David S. Miller" Date: Mon, 4 Aug 2014 16:34:01 -0700 Subject: [PATCH] sparc64: Do not insert non-valid PTEs into the TSB hash table. [ Upstream commit 18f38132528c3e603c66ea464727b29e9bbcb91b ] The assumption was that update_mmu_cache() (and the equivalent for PMDs) would only be called when the PTE being installed will be accessible by the user. This is not true for code paths originating from remove_migration_pte(). There are dire consequences for placing a non-valid PTE into the TSB. The TLB miss frramework assumes thatwhen a TSB entry matches we can just load it into the TLB and return from the TLB miss trap. So if a non-valid PTE is in there, we will deadlock taking the TLB miss over and over, never satisfying the miss. Just exit early from update_mmu_cache() and friends in this situation. Based upon a report and patch from Christopher Alexander Tobias Schulze. Signed-off-by: David S. Miller Signed-off-by: Ben Hutchings --- Reading git-format-patch failed