* elf/tst-tls4.c: Define an unused TLS variable here, so that no lazy

TLS setup is required.
	* elf/tst-tls5.c: Likewise.
	* elf/tst-tls6.c: Likewise.
	* elf/tst-tls7.c: Likewise.
	* elf/tst-tls8.c: Likewise.
	* elf/tst-tls9.c: Likewise.

	* elf/rtld.c (dl_main): Remove [! SHARED] conditional from
	`if (GL(dl_tls_max_dtv_idx) > 0)' tests for doing TLS setup.
	* elf/dl-close.c (libc_freeres_fn): Check GL(dl_tls_dtv_slotinfo_list)
	for being null before calling free_slotinfo.
	* elf/dl-load.c (_dl_map_object_from_fd) [SHARED]: For PT_TLS in
	dynamic loading, bail with error if GL(dl_tls_max_dtv_idx) is zero.

ChangeLog

@@ -1,3 +1,20 @@
+2002-12-02  Roland McGrath  <roland@redhat.com>
+
+	* elf/tst-tls4.c: Define an unused TLS variable here, so that no lazy
+	TLS setup is required.
+	* elf/tst-tls5.c: Likewise.
+	* elf/tst-tls6.c: Likewise.
+	* elf/tst-tls7.c: Likewise.
+	* elf/tst-tls8.c: Likewise.
+	* elf/tst-tls9.c: Likewise.
+
+	* elf/rtld.c (dl_main): Remove [! SHARED] conditional from
+	`if (GL(dl_tls_max_dtv_idx) > 0)' tests for doing TLS setup.
+	* elf/dl-close.c (libc_freeres_fn): Check GL(dl_tls_dtv_slotinfo_list)
+	for being null before calling free_slotinfo.
+	* elf/dl-load.c (_dl_map_object_from_fd) [SHARED]: For PT_TLS in
+	dynamic loading, bail with error if GL(dl_tls_max_dtv_idx) is zero.
+
 2002-11-30  Bruno Haible  <bruno@clisp.org>
 
 	* iconv/gconv.h (__gconv_btowc_fct): New typedef.

elf/dl-close.c

@@ -476,6 +476,8 @@ libc_freeres_fn (free_mem)
     }
 
 #ifdef USE_TLS
+  if (USE___THREAD || GL(dl_tls_dtv_slotinfo_list) != NULL)
+    {
       /* Free the memory allocated for the dtv slotinfo array.  We can do
 	 this only if all modules which used this memory are unloaded.
 	 Also, the first element of the list does not have to be
@@ -483,5 +485,6 @@ libc_freeres_fn (free_mem)
 	 a different malloc).  */
       if (free_slotinfo (GL(dl_tls_dtv_slotinfo_list)->next))
 	GL(dl_tls_dtv_slotinfo_list)->next = NULL;
+    }
 #endif
 }

elf/dl-load.c

@@ -942,7 +942,19 @@ _dl_map_object_from_fd (const char *name, int fd, struct filebuf *fbp,
 
 	case PT_TLS:
 #ifdef USE_TLS
-	  if (ph->p_memsz > 0)
+	  if (ph->p_memsz == 0)
+	    /* Nothing to do for an empty segment.  */
+	    break;
+
+	  /* If not loading the initial set of shared libraries,
+	     check whether we should permit loading a TLS segment.  */
+	  if (
+# ifdef SHARED
+	      __builtin_expect (l->l_type == lt_library, 1) ||
+# endif
+	      /* If GL(dl_tls_max_dtv_idx) == 0, then rtld.c did not
+		 set up TLS data structures, so don't use them now.  */
+	      __builtin_expect (GL(dl_tls_max_dtv_idx), 1) != 0)
 	    {
 	      l->l_tls_blocksize = ph->p_memsz;
 	      l->l_tls_align = ph->p_align;
@@ -953,14 +965,20 @@ _dl_map_object_from_fd (const char *name, int fd, struct filebuf *fbp,
 
 	      /* Assign the next available module ID.  */
 	      l->l_tls_modid = _dl_next_tls_modid ();
+	      break;
 	    }
-#else
+
+	  if (l->l_prev == NULL)
+	    /* We are loading the executable itself when the dynamic linker
+	       was executed directly.  The setup will happen later.  */
+	    break;
+#endif
+
 	  /* Uh-oh, the binary expects TLS support but we cannot
 	     provide it.  */
 	  errval = 0;
 	  errstring = N_("cannot handle TLS data");
 	  goto call_lose;
-#endif
 	  break;
 	}
 

elf/rtld.c

@@ -1139,12 +1139,14 @@ of this helper program; chances are you did not intend to run this program.\n\
     /* Assign a module ID.  */
     GL(dl_rtld_map).l_tls_modid = _dl_next_tls_modid ();
 
-# ifndef SHARED
-  /* If dynamic loading of modules with TLS is impossible we do not
-     have to initialize any of the TLS functionality unless any of the
-     initial modules uses TLS.  */
+  /* We do not initialize any of the TLS functionality unless any of the
+     initial modules uses TLS.  This makes dynamic loading of modules with
+     TLS impossible, but to support it requires either eagerly doing setup
+     now or lazily doing it later.  Doing it now makes us incompatible with
+     an old kernel that can't perform TLS_INIT_TP, even if no TLS is ever
+     used.  Trying to do it lazily is too hairy to try when there could be
+     multiple threads (from a non-TLS-using libpthread).  */
   if (GL(dl_tls_max_dtv_idx) > 0)
-# endif
     {
       struct link_map *l;
       size_t nelem;
@@ -1555,9 +1557,7 @@ cannot allocate TLS data structures for initial thread");
   GL(dl_initial_searchlist) = *GL(dl_main_searchlist);
 
 #ifdef USE_TLS
-# ifndef SHARED
-  if (GL(dl_tls_max_dtv_idx) > 0)
-# endif
+  if (GL(dl_tls_max_dtv_idx) > 0 || USE___THREAD)
     {
       /* Now that we have completed relocation, the initializer data
 	 for the TLS blocks has its final values and we can copy them

elf/tst-tls4.c

@@ -4,6 +4,14 @@
 
 #include <tls.h>
 
+#ifdef USE_TLS
+# include "tls-macros.h"
+
+/* This gives the executable a TLS segment so that even if the libc.so
+   it loads has none (i.e. --with-tls --without-__thread), ld.so will
+   permit loading of objects with TLS segments.  */
+COMMON_INT_DEF(loser);
+#endif
 
 #define TEST_FUNCTION do_test ()
 static int

elf/tst-tls5.c

@@ -4,6 +4,15 @@
 
 #include <tls.h>
 
+#ifdef USE_TLS
+# include "tls-macros.h"
+
+/* This gives the executable a TLS segment so that even if the libc.so
+   it loads has none (i.e. --with-tls --without-__thread), ld.so will
+   permit loading of objects with TLS segments.  */
+COMMON_INT_DEF(loser);
+#endif
+
 
 #define TEST_FUNCTION do_test ()
 static int

elf/tst-tls6.c

@@ -5,6 +5,15 @@
 #include <link.h>
 #include <tls.h>
 
+#ifdef USE_TLS
+# include "tls-macros.h"
+
+/* This gives the executable a TLS segment so that even if the libc.so
+   it loads has none (i.e. --with-tls --without-__thread), ld.so will
+   permit loading of objects with TLS segments.  */
+COMMON_INT_DEF(loser);
+#endif
+
 
 #define TEST_FUNCTION do_test ()
 static int

elf/tst-tls7.c

@@ -5,6 +5,15 @@
 #include <link.h>
 #include <tls.h>
 
+#ifdef USE_TLS
+# include "tls-macros.h"
+
+/* This gives the executable a TLS segment so that even if the libc.so
+   it loads has none (i.e. --with-tls --without-__thread), ld.so will
+   permit loading of objects with TLS segments.  */
+COMMON_INT_DEF(loser);
+#endif
+
 
 #define TEST_FUNCTION do_test ()
 static int

elf/tst-tls8.c

@@ -5,6 +5,15 @@
 #include <link.h>
 #include <tls.h>
 
+#ifdef USE_TLS
+# include "tls-macros.h"
+
+/* This gives the executable a TLS segment so that even if the libc.so
+   it loads has none (i.e. --with-tls --without-__thread), ld.so will
+   permit loading of objects with TLS segments.  */
+COMMON_INT_DEF(loser);
+#endif
+
 
 #define TEST_FUNCTION do_test ()
 static int

elf/tst-tls9.c

@@ -5,6 +5,15 @@
 #include <link.h>
 #include <tls.h>
 
+#ifdef USE_TLS
+# include "tls-macros.h"
+
+/* This gives the executable a TLS segment so that even if the libc.so
+   it loads has none (i.e. --with-tls --without-__thread), ld.so will
+   permit loading of objects with TLS segments.  */
+COMMON_INT_DEF(loser);
+#endif
+
 
 #define TEST_FUNCTION do_test ()
 static int

linuxthreads/sysdeps/i386/tls.h

@@ -43,8 +43,17 @@ typedef struct
 #endif
 
 
-/* We can support TLS only if the floating-stack support is available.  */
-#if defined FLOATING_STACKS && defined HAVE_TLS_SUPPORT
+/* We can support TLS only if the floating-stack support is available.
+   However, we want to compile in the support and test at runtime whether
+   the running kernel can support it or not.  To avoid bothering with the
+   TLS support code at all, use configure --without-tls.
+
+   We need USE_TLS to be consistently defined, for ldsodefs.h conditionals.
+   But some of the code below can cause problems in building libpthread
+   (e.g. useldt.h will defined FLOATING_STACKS when it shouldn't).  */
+
+#if defined HAVE_TLS_SUPPORT \
+    && (defined FLOATING_STACKS || !defined IS_IN_libpthread)
 
 /* Signal that TLS support is available.  */
 # define USE_TLS	1
@@ -96,8 +105,21 @@ typedef struct
 #   define TLS_LOAD_EBX
 #  endif
 
+#  if __ASSUME_LDT_WORKS > 0
+#   define TLS_DO_MODIFY_LDT_KERNEL_CHECK /* Nothing to do.  */
+#  else
+#   include "useldt.h"		/* For the structure.  */
+#   define TLS_DO_MODIFY_LDT_KERNEL_CHECK				      \
+  if (__builtin_expect (GL(dl_osversion) < 131939, 0))			      \
+    _dl_fatal_printf ("kernel %u.%u.%u cannot support thread-local storage\n",\
+		      (GL(dl_osversion) >> 16) & 0xff,			      \
+		      (GL(dl_osversion) >> 8) & 0xff,			      \
+		      (GL(dl_osversion) >> 0) & 0xff);
+#  endif
+
 #  define TLS_DO_MODIFY_LDT(descr, nr)					      \
 ({									      \
+  TLS_DO_MODIFY_LDT_KERNEL_CHECK					      \
   struct modify_ldt_ldt_s ldt_entry =					      \
     { nr, (unsigned long int) (descr), 0xfffff /* 4GB in pages */,	      \
       1, 0, 0, 1, 0, 1, 0 };						      \
@@ -177,7 +199,7 @@ typedef struct
   ({ struct _pthread_descr_struct *__descr;				      \
      THREAD_GETMEM (__descr, p_header.data.dtvp); })
 
-# endif	/* FLOATING_STACKS && HAVE_TLS_SUPPORT */
+# endif	/* HAVE_TLS_SUPPORT && (FLOATING_STACKS || !IS_IN_libpthread) */
 #endif /* __ASSEMBLER__ */
 
 #endif	/* tls.h */

linuxthreads/tst-context.c

@@ -1,3 +1,12 @@
+/* Ack, a hack!  We need to get the proper definition, or lack thereof,
+   for FLOATING_STACKS.  But when !IS_IN_libpthread, this can get defined
+   incidentally by <tls.h>.  So kludge around it.  */
+
+#define IS_IN_libpthread
+#include <tls.h>
+#undef IS_IN_libpthread
+#undef USE___THREAD
+
 #include <errno.h>
 #include <error.h>
 #include <pthread.h>
@@ -5,8 +14,6 @@
 #include <stdlib.h>
 #include <ucontext.h>
 
-#include "pt-machine.h"
-
 
 #define N	4