From: David S. Miller Date: Mon, 4 Aug 2014 23:34:01 +0000 (-0700) Subject: sparc64: Do not insert non-valid PTEs into the TSB hash table. X-Git-Tag: omap-for-v3.17/fixes-against-rc2~148^2~1^2~6 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=18f38132528c3e603c66ea464727b29e9bbcb91b;p=pandora-kernel.git sparc64: Do not insert non-valid PTEs into the TSB hash table. 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 --- Reading git-diff-tree failed