From: Maxim Dounin <mdounin@mdounin.ru>
Date: Mon, 10 Dec 2012 18:17:32 +0000 (+0000)
Subject: Merge of r4933, r4933: shared memory fixes.
X-Git-Tag: release-1.2.6~2
X-Git-Url: http://git.kaiwu.me/postgresql/log/contrib/postgres_fdw/static/gitweb.js?a=commitdiff_plain;h=f45e938b89d0ef3967bf95216bd3f63ef5e65429;p=nginx.git

Merge of r4933, r4933: shared memory fixes.

*) Fixed location of debug message in ngx_shmtx_lock().

*) Core: don't reuse shared memory zone that changed ownership (ticket #210).

   nginx doesn't allow the same shared memory zone to be used for different
   purposes, but failed to check this on reconfiguration.  If a shared memory
   zone was used for another purpose in the new configuration, nginx attempted
   to reuse it and crashed.
---

diff --git a/src/core/ngx_cycle.c b/src/core/ngx_cycle.c
index f15372990..e8b155921 100644
--- a/src/core/ngx_cycle.c
+++ b/src/core/ngx_cycle.c
@@ -447,7 +447,9 @@ ngx_init_cycle(ngx_cycle_t *old_cycle)
                 continue;
             }
 
-            if (shm_zone[i].shm.size == oshm_zone[n].shm.size) {
+            if (shm_zone[i].tag == oshm_zone[n].tag
+                && shm_zone[i].shm.size == oshm_zone[n].shm.size)
+            {
                 shm_zone[i].shm.addr = oshm_zone[n].shm.addr;
 
                 if (shm_zone[i].init(&shm_zone[i], oshm_zone[n].data)
diff --git a/src/core/ngx_shmtx.c b/src/core/ngx_shmtx.c
index 6cf7af58a..a62999f33 100644
--- a/src/core/ngx_shmtx.c
+++ b/src/core/ngx_shmtx.c
@@ -117,11 +117,11 @@ ngx_shmtx_lock(ngx_shmtx_t *mtx)
                                   "sem_wait() failed while waiting on shmtx");
                     break;
                 }
-
-                ngx_log_debug0(NGX_LOG_DEBUG_CORE, ngx_cycle->log, 0,
-                               "shmtx awoke");
             }
 
+            ngx_log_debug0(NGX_LOG_DEBUG_CORE, ngx_cycle->log, 0,
+                           "shmtx awoke");
+
             continue;
         }