mirror of
https://sourceware.org/git/glibc.git
synced 2024-09-18 23:49:57 +00:00
0aac205a81
Compiler generates the following instruction sequence for GNU2 dynamic TLS access: leaq tls_var@TLSDESC(%rip), %rax call *tls_var@TLSCALL(%rax) or leal tls_var@TLSDESC(%ebx), %eax call *tls_var@TLSCALL(%eax) CALL instruction is transparent to compiler which assumes all registers, except for EFLAGS and RAX/EAX, are unchanged after CALL. When _dl_tlsdesc_dynamic is called, it calls __tls_get_addr on the slow path. __tls_get_addr is a normal function which doesn't preserve any caller-saved registers. _dl_tlsdesc_dynamic saved and restored integer caller-saved registers, but didn't preserve any other caller-saved registers. Add _dl_tlsdesc_dynamic IFUNC functions for FNSAVE, FXSAVE, XSAVE and XSAVEC to save and restore all caller-saved registers. This fixes BZ #31372. Add GLRO(dl_x86_64_runtime_resolve) with GLRO(dl_x86_tlsdesc_dynamic) to optimize elf_machine_runtime_setup. Reviewed-by: Noah Goldstein <goldstein.w.n@gmail.com>
123 lines
3.0 KiB
C
123 lines
3.0 KiB
C
/* Test TLSDESC relocation.
|
|
Copyright (C) 2024 Free Software Foundation, Inc.
|
|
This file is part of the GNU C Library.
|
|
|
|
The GNU C Library is free software; you can redistribute it and/or
|
|
modify it under the terms of the GNU Lesser General Public
|
|
License as published by the Free Software Foundation; either
|
|
version 2.1 of the License, or (at your option) any later version.
|
|
|
|
The GNU C Library is distributed in the hope that it will be useful,
|
|
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
|
Lesser General Public License for more details.
|
|
|
|
You should have received a copy of the GNU Lesser General Public
|
|
License along with the GNU C Library; if not, see
|
|
<http://www.gnu.org/licenses/>. */
|
|
|
|
#include <stdio.h>
|
|
#include <stdlib.h>
|
|
#include <string.h>
|
|
#include <dlfcn.h>
|
|
#include <pthread.h>
|
|
#include <support/xdlfcn.h>
|
|
#include <support/xthread.h>
|
|
#include <support/check.h>
|
|
#include <support/test-driver.h>
|
|
#include "tst-gnu2-tls2.h"
|
|
|
|
#ifndef IS_SUPPORTED
|
|
# define IS_SUPPORTED() true
|
|
#endif
|
|
|
|
/* An architecture can define it to clobber caller-saved registers in
|
|
malloc below to verify that the implicit TLSDESC call won't change
|
|
caller-saved registers. */
|
|
#ifndef PREPARE_MALLOC
|
|
# define PREPARE_MALLOC()
|
|
#endif
|
|
|
|
extern void * __libc_malloc (size_t);
|
|
|
|
size_t malloc_counter = 0;
|
|
|
|
void *
|
|
malloc (size_t n)
|
|
{
|
|
PREPARE_MALLOC ();
|
|
malloc_counter++;
|
|
return __libc_malloc (n);
|
|
}
|
|
|
|
static void *mod[3];
|
|
#ifndef MOD
|
|
# define MOD(i) "tst-gnu2-tls2mod" #i ".so"
|
|
#endif
|
|
static const char *modname[3] = { MOD(0), MOD(1), MOD(2) };
|
|
#undef MOD
|
|
|
|
static void
|
|
open_mod (int i)
|
|
{
|
|
mod[i] = xdlopen (modname[i], RTLD_LAZY);
|
|
printf ("open %s\n", modname[i]);
|
|
}
|
|
|
|
static void
|
|
close_mod (int i)
|
|
{
|
|
xdlclose (mod[i]);
|
|
mod[i] = NULL;
|
|
printf ("close %s\n", modname[i]);
|
|
}
|
|
|
|
static void
|
|
access_mod (int i, const char *sym)
|
|
{
|
|
struct tls var = { -1, -1, -1, -1 };
|
|
struct tls *(*f) (struct tls *) = xdlsym (mod[i], sym);
|
|
/* Check that our malloc is called. */
|
|
malloc_counter = 0;
|
|
struct tls *p = f (&var);
|
|
TEST_VERIFY (malloc_counter != 0);
|
|
printf ("access %s: %s() = %p\n", modname[i], sym, p);
|
|
TEST_VERIFY_EXIT (memcmp (p, &var, sizeof (var)) == 0);
|
|
++(p->a);
|
|
}
|
|
|
|
static void *
|
|
start (void *arg)
|
|
{
|
|
/* The DTV generation is at the last dlopen of mod0 and the
|
|
entry for mod1 is NULL. */
|
|
|
|
open_mod (1); /* Reuse modid of mod1. Uses dynamic TLS. */
|
|
|
|
/* Force the slow path in GNU2 TLS descriptor call. */
|
|
access_mod (1, "apply_tls");
|
|
|
|
return arg;
|
|
}
|
|
|
|
static int
|
|
do_test (void)
|
|
{
|
|
if (!IS_SUPPORTED ())
|
|
return EXIT_UNSUPPORTED;
|
|
|
|
open_mod (0);
|
|
open_mod (1);
|
|
open_mod (2);
|
|
close_mod (0);
|
|
close_mod (1); /* Create modid gap at mod1. */
|
|
open_mod (0); /* Reuse modid of mod0, bump generation count. */
|
|
|
|
/* Create a thread where DTV of mod1 is NULL. */
|
|
pthread_t t = xpthread_create (NULL, start, NULL);
|
|
xpthread_join (t);
|
|
return 0;
|
|
}
|
|
|
|
#include <support/test-driver.c>
|