>From 9bc05ac103c77fcd2276754a3ccbf49e66dd00b7 Mon Sep 17 00:00:00 2001 From: Andres Freund Date: Tue, 6 May 2014 19:08:07 +0200 Subject: [PATCH] Don't bail in dsm_attach() if any any other segment is about to be destroyed. The previous coding accidentally checked for refcnt == 1, which signals moribund segments, before checking whether the segment we're looking at is the one we're trying to attach to. --- src/backend/storage/ipc/dsm.c | 15 ++++++++------- 1 file changed, 8 insertions(+), 7 deletions(-) diff --git a/src/backend/storage/ipc/dsm.c b/src/backend/storage/ipc/dsm.c index d86b0c7..bde7026 100644 --- a/src/backend/storage/ipc/dsm.c +++ b/src/backend/storage/ipc/dsm.c @@ -570,6 +570,10 @@ dsm_attach(dsm_handle h) if (dsm_control->item[i].refcnt == 0) continue; + /* Not the segment you're looking for. */ + if (dsm_control->item[i].handle != seg->handle) + continue; + /* * If the reference count is 1, the slot is still in use, but the * segment is in the process of going away. Treat that as if we @@ -578,13 +582,10 @@ dsm_attach(dsm_handle h) if (dsm_control->item[i].refcnt == 1) break; - /* Otherwise, if the descriptor matches, we've found a match. */ - if (dsm_control->item[i].handle == seg->handle) - { - dsm_control->item[i].refcnt++; - seg->control_slot = i; - break; - } + /* Otherwise we've found a match. */ + dsm_control->item[i].refcnt++; + seg->control_slot = i; + break; } LWLockRelease(DynamicSharedMemoryControlLock); -- 1.8.5.rc2.dirty