Update.

	* elf/rtld.c: Split _dl_start in two pieces to prevent GOT usage
	before the relocation happened.
	Patch by Franz Sirl <Franz.Sirl-kernel@lauterbach.com>.

diff --git a/ChangeLog b/ChangeLog
index 37b8ff2..f4dce34 100644 (file)
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,9 @@
 1999-07-09  Ulrich Drepper  <drepper@cygnus.com>
 
+       * elf/rtld.c: Split _dl_start in two pieces to prevent GOT usage
+       before the relocation happened.
+       Patch by Franz Sirl <Franz.Sirl-kernel@lauterbach.com>.
+
        * Versions.def (libnsl): Add GLIBC_2.2.
        * nis/Versions (libnsl) [GLIBC_2.2]: Add xdr_ypall.
 

diff --git a/elf/rtld.c b/elf/rtld.c
index 064cd20..4146c0e 100644 (file)
--- a/elf/rtld.c
+++ b/elf/rtld.c
@@ -129,6 +129,9 @@ static hp_timing_t relocate_time;
 static hp_timing_t load_time;
 extern unsigned long int _dl_num_relocations;  /* in dl-lookup.c */
 
+static ElfW(Addr) _dl_start_final (void *arg, struct link_map *bootstrap_map_p,
+                                  hp_timing_t start_time);
+
 #ifdef RTLD_START
 RTLD_START
 #else
@@ -140,7 +143,6 @@ _dl_start (void *arg)
 {
   struct link_map bootstrap_map;
   hp_timing_t start_time;
-  ElfW(Addr) start_addr;
 
   /* This #define produces dynamic linking inline functions for
      bootstrap relocation instead of general-purpose relocation.  */
@@ -175,7 +177,22 @@ _dl_start (void *arg)
   /* Now life is sane; we can call functions and access global data.
      Set up to use the operating system facilities, and find out from
      the operating system's program loader where to find the program
-     header table in core.  */
+     header table in core.  Put the rest of _dl_start into a separate
+     function, that way the compiler cannot put accesses to the GOT
+     before ELF_DYNAMIC_RELOCATE.  */
+  return _dl_start_final (arg, &bootstrap_map, start_time);
+}
+
+
+static ElfW(Addr)
+_dl_start_final (void *arg, struct link_map *bootstrap_map_p,
+                hp_timing_t start_time)
+{
+  /* The use of `alloca' here looks ridiculous but it helps.  The goal
+     is to avoid the function from being inlined.  There is no official
+     way to do this so we use this trick.  gcc never inlines functions
+     which use `alloca'.  */
+  ElfW(Addr) *start_addr = alloca (sizeof (ElfW(Addr)));
 
   if (HP_TIMING_AVAIL)
     {
@@ -188,10 +205,10 @@ _dl_start (void *arg)
     }
 
   /* Transfer data about ourselves to the permanent link_map structure.  */
-  _dl_rtld_map.l_addr = bootstrap_map.l_addr;
-  _dl_rtld_map.l_ld = bootstrap_map.l_ld;
+  _dl_rtld_map.l_addr = bootstrap_map_p->l_addr;
+  _dl_rtld_map.l_ld = bootstrap_map_p->l_ld;
   _dl_rtld_map.l_opencount = 1;
-  memcpy (_dl_rtld_map.l_info, bootstrap_map.l_info,
+  memcpy (_dl_rtld_map.l_info, bootstrap_map_p->l_info,
          sizeof _dl_rtld_map.l_info);
   _dl_setup_hash (&_dl_rtld_map);
 
@@ -203,7 +220,7 @@ _dl_start (void *arg)
      file access.  It will call `dl_main' (below) to do all the real work
      of the dynamic linker, and then unwind our frame and run the user
      entry point on the same stack we entered on.  */
-  start_addr =  _dl_sysdep_start (arg, &dl_main);
+  *start_addr =  _dl_sysdep_start (arg, &dl_main);
 
   if (HP_TIMING_AVAIL)
     {
@@ -219,7 +236,7 @@ _dl_start (void *arg)
   if (_dl_debug_statistics)
     print_statistics ();
 
-  return start_addr;
+  return *start_addr;
 }
 
 /* Now life is peachy; we can do all normal operations.

diff --git a/linuxthreads/ChangeLog b/linuxthreads/ChangeLog
index ab97529..dfb0e3d 100644 (file)
--- a/linuxthreads/ChangeLog
+++ b/linuxthreads/ChangeLog
@@ -1,3 +1,11 @@
+1999-06-23  Robey Pointer  <robey@netscape.com>
+
+       * internals.h: Added p_nextlock entry to separate queueing for a
+       lock from queueing for a CV (sometimes a thread queues on a lock
+       to serialize removing itself from a CV queue).
+       * pthread.c: Added p_nextlock to initializers.
+       * spinlock.c: Changed to use p_nextlock instead of p_nextwaiting.
+
 1999-07-09  Ulrich Drepper  <drepper@cygnus.com>
 
        * manager.c (pthread_handle_create): Free mmap region after stack

diff --git a/linuxthreads/internals.h b/linuxthreads/internals.h
index db84707..bcbfbcf 100644 (file)
--- a/linuxthreads/internals.h
+++ b/linuxthreads/internals.h
@@ -74,6 +74,7 @@ struct _pthread_descr_struct {
   pthread_descr p_nextlive, p_prevlive;
                                 /* Double chaining of active threads */
   pthread_descr p_nextwaiting;  /* Next element in the queue holding the thr */
+  pthread_descr p_nextlock;    /* can be on a queue and waiting on a lock */
   pthread_t p_tid;              /* Thread identifier */
   int p_pid;                    /* PID of Unix process */
   int p_priority;               /* Thread priority (== 0 if not realtime) */

diff --git a/linuxthreads/pthread.c b/linuxthreads/pthread.c
index b7cf573..c94e7e6 100644 (file)
--- a/linuxthreads/pthread.c
+++ b/linuxthreads/pthread.c
@@ -34,6 +34,7 @@ struct _pthread_descr_struct __pthread_initial_thread = {
   &__pthread_initial_thread,  /* pthread_descr p_nextlive */
   &__pthread_initial_thread,  /* pthread_descr p_prevlive */
   NULL,                       /* pthread_descr p_nextwaiting */
+  NULL,                              /* pthread_descr p_nextlock */
   PTHREAD_THREADS_MAX,        /* pthread_t p_tid */
   0,                          /* int p_pid */
   0,                          /* int p_priority */
@@ -75,6 +76,7 @@ struct _pthread_descr_struct __pthread_manager_thread = {
   NULL,                       /* pthread_descr p_nextlive */
   NULL,                       /* pthread_descr p_prevlive */
   NULL,                       /* pthread_descr p_nextwaiting */
+  NULL,                              /* pthread_descr p_nextlock */
   0,                          /* int p_tid */
   0,                          /* int p_pid */
   0,                          /* int p_priority */

diff --git a/linuxthreads/spinlock.c b/linuxthreads/spinlock.c
index c8f8f71..ce6ff9e 100644 (file)
--- a/linuxthreads/spinlock.c
+++ b/linuxthreads/spinlock.c
@@ -27,7 +27,7 @@
      1: fastlock is taken, no thread is waiting on it
   ADDR: fastlock is taken, ADDR is address of thread descriptor for
         first waiting thread, other waiting threads are linked via
-        their p_nextwaiting field.
+        their p_nextlock field.
    The waiting list is not sorted by priority order.
    Actually, we always insert at top of list (sole insertion mode
    that can be performed without locking).
@@ -50,8 +50,10 @@ void internal_function __pthread_lock(struct _pthread_fastlock * lock,
        self = thread_self();
       newstatus = (long) self;
     }
-    if (self != NULL)
-      THREAD_SETMEM(self, p_nextwaiting, (pthread_descr) oldstatus);
+    if (self != NULL) {
+      ASSERT(self->p_nextlock == NULL);
+      THREAD_SETMEM(self, p_nextlock, (pthread_descr) oldstatus);
+    }
   } while(! compare_and_swap(&lock->__status, oldstatus, newstatus,
                              &lock->__spinlock));
   if (oldstatus != 0) suspend(self);
@@ -83,7 +85,7 @@ again:
       maxptr = ptr;
       maxprio = thr->p_priority;
     }
-    ptr = &(thr->p_nextwaiting);
+    ptr = &(thr->p_nextlock);
     thr = *ptr;
   }
   /* Remove max prio thread from waiting list. */
@@ -92,16 +94,16 @@ again:
        to guard against concurrent lock operation */
     thr = (pthread_descr) oldstatus;
     if (! compare_and_swap(&lock->__status,
-                           oldstatus, (long)(thr->p_nextwaiting),
+                           oldstatus, (long)(thr->p_nextlock),
                            &lock->__spinlock))
       goto again;
   } else {
     /* No risk of concurrent access, remove max prio thread normally */
     thr = *maxptr;
-    *maxptr = thr->p_nextwaiting;
+    *maxptr = thr->p_nextlock;
   }
   /* Wake up the selected waiting thread */
-  thr->p_nextwaiting = NULL;
+  thr->p_nextlock = NULL;
   restart(thr);
 }