From: Juho Snellman <jsnell@iki.fi>
Date: Tue, 27 Sep 2005 16:58:47 +0000 (+0000)
Subject: 0.9.5.2:
X-Git-Url: http://repo.macrolet.net/gitweb/?a=commitdiff_plain;h=b319107330cea71911b346974508c699f8b7fe6c;p=sbcl.git

0.9.5.2:
	Yet another personality() change, this time for some Linux kernels
        that don't change the personality, but nor return an error code.
        Patch by Svein Ove Aas on sbcl-devel, "[PATCH] Workaround buggy
        personality() call on old Linux kernels".

        Reformat isnptl().
---

diff --git a/NEWS b/NEWS
index 4f2cf44..924cc35 100644
--- a/NEWS
+++ b/NEWS
@@ -1,4 +1,9 @@
 ;;;; -*- coding: utf-8; -*-
+changes in sbcl-0.9.6 relative to sbcl-0.9.5:
+  * bug fix: add a workaround to SBCL looping infinitely at startup on 
+    Linux kernels with apparently buggy implementations of personality().
+    (thanks to Svein Ove Aas)
+
 changes in sbcl-0.9.5 relative to sbcl-0.9.4:
   * new feature: timers based on Zach Beane's excellent timer package
   * added support for the following external formats: koi8-u,
diff --git a/src/runtime/linux-os.c b/src/runtime/linux-os.c
index 9bc5ea1..4cbd8c9 100644
--- a/src/runtime/linux-os.c
+++ b/src/runtime/linux-os.c
@@ -98,16 +98,17 @@ int linux_sparc_siginfo_bug = 0;
 int linux_no_threads_p = 0;
 
 #ifdef LISP_FEATURE_SB_THREAD
-int isnptl (void)
+int
+isnptl (void)
 {
   size_t n = confstr (_CS_GNU_LIBPTHREAD_VERSION, NULL, 0);
-  if (n > 0)
-    {
+  if (n > 0) {
       char *buf = alloca (n);
       confstr (_CS_GNU_LIBPTHREAD_VERSION, buf, n);
-      if (strstr (buf, "NPTL"))
-        return 1;
-    }
+      if (strstr (buf, "NPTL")) {
+          return 1;
+      }
+  }
   return 0;
 }
 #endif
@@ -163,10 +164,21 @@ Please use a more recent kernel or a version of SBCL without threading support.\
     if ((major_version == 2 && minor_version >= 6)
         || major_version >= 3)
     {
-        long pers = personality(-1);
+        int pers = personality(0xffffffffUL);
         /* 0x40000 aka. ADDR_NO_RANDOMIZE */
         if (!(pers & 0x40000)) {
-            if (personality(pers | 0x40000) != -1) {
+            int retval = personality(pers | 0x40000);
+            /* Allegedly some Linux kernels (the reported case was
+             * "hardened Linux 2.6.7") won't set the new personality,
+             * but nor will they return -1 for an error. So as a
+             * workaround query the new personality...
+             */
+            int newpers = personality(0xffffffffUL);
+            /* ... and don't re-execute if either the setting resulted
+             * in an error or if the value didn't change. Otherwise
+             * this might result in an infinite loop.
+             */
+            if (retval != -1 && newpers != pers) {        
                 /* Use /proc/self/exe instead of trying to figure out
                  * the executable path from PATH and argv[0], since
                  * that's unreliable. We follow the symlink instead of
diff --git a/version.lisp-expr b/version.lisp-expr
index 1fee710..eb3ba00 100644
--- a/version.lisp-expr
+++ b/version.lisp-expr
@@ -17,4 +17,4 @@
 ;;; checkins which aren't released. (And occasionally for internal
 ;;; versions, especially for internal versions off the main CVS
 ;;; branch, it gets hairier, e.g. "0.pre7.14.flaky4.13".)
-"0.9.5.1"
+"0.9.5.2"