From patchwork Fri Mar 13 03:04:14 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Vineet Gupta X-Patchwork-Id: 38546 Return-Path: X-Original-To: libc-alpha@sourceware.org Delivered-To: libc-alpha@sourceware.org Received: from smtprelay-out1.synopsys.com (smtprelay-out1.synopsys.com [149.117.73.133]) by sourceware.org (Postfix) with ESMTPS id 886B53AA801C for ; Fri, 13 Mar 2020 03:04:32 +0000 (GMT) Received: from mailhost.synopsys.com (sv1-mailhost2.synopsys.com [10.205.2.132]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by smtprelay-out1.synopsys.com (Postfix) with ESMTPS id C37BA40216; Fri, 13 Mar 2020 03:04:31 +0000 (UTC) Received: from vineetg-Latitude-E7450.internal.synopsys.com (unknown [10.13.182.230]) by mailhost.synopsys.com (Postfix) with ESMTP id 92780A0082; Fri, 13 Mar 2020 03:04:31 +0000 (UTC) From: Vineet Gupta To: libc-alpha@sourceware.org Cc: linux-snps-arc@lists.infradead.org, Vineet Gupta Subject: [PATCH v4 10/15] ARC: Linux Startup and Dynamic Loading Date: Thu, 12 Mar 2020 20:04:14 -0700 Message-Id: <20200313030419.15843-11-vgupta@synopsys.com> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200313030419.15843-1-vgupta@synopsys.com> References: <20200313030419.15843-1-vgupta@synopsys.com> MIME-Version: 1.0 X-Spam-Status: No, score=-27.1 required=5.0 tests=BAYES_00, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, GIT_PATCH_0, GIT_PATCH_1, GIT_PATCH_2, GIT_PATCH_3, SPF_HELO_NONE, SPF_PASS autolearn=ham autolearn_force=no version=3.4.2 X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on server2.sourceware.org X-BeenThere: libc-alpha@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Libc-alpha mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 13 Mar 2020 03:04:34 -0000 Signed-off-by: Vineet Gupta --- sysdeps/arc/start.S | 15 +++-- sysdeps/unix/sysv/linux/arc/dl-static.c | 84 +++++++++++++++++++++++++ sysdeps/unix/sysv/linux/arc/ldsodefs.h | 32 ++++++++++ 3 files changed, 125 insertions(+), 6 deletions(-) create mode 100644 sysdeps/unix/sysv/linux/arc/dl-static.c create mode 100644 sysdeps/unix/sysv/linux/arc/ldsodefs.h diff --git a/sysdeps/arc/start.S b/sysdeps/arc/start.S index e006453dcd1f..25e43d71da9e 100644 --- a/sysdeps/arc/start.S +++ b/sysdeps/arc/start.S @@ -18,6 +18,8 @@ #define __ASSEMBLY__ 1 #include +#include + #ifndef ENTRY_POINT # error ENTRY_POINT needs to be defined for ARC #endif @@ -31,11 +33,12 @@ env[0...N] environment variables (pointers) NULL. */ - .text - .align 4 - .global __start - .type __start,@function -__start: +ENTRY (ENTRY_POINT) + + /* Needed to make gdb backtraces stop here. */ + .cfi_label .Ldummy + cfi_undefined (blink) + mov fp, 0 ld_s r1, [sp] ; argc @@ -60,7 +63,7 @@ __start: /* Should never get here. */ flag 1 - .size __start,.-__start +END (ENTRY_POINT) /* Define a symbol for the first piece of initialized data. */ .data diff --git a/sysdeps/unix/sysv/linux/arc/dl-static.c b/sysdeps/unix/sysv/linux/arc/dl-static.c new file mode 100644 index 000000000000..24c31b27fc11 --- /dev/null +++ b/sysdeps/unix/sysv/linux/arc/dl-static.c @@ -0,0 +1,84 @@ +/* Variable initialization. ARC version. + Copyright (C) 2001-2020 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 + . */ + +#include + +#ifdef SHARED + +void +_dl_var_init (void *array[]) +{ + /* It has to match "variables" below. */ + enum + { + DL_PAGESIZE = 0 + }; + + GLRO(dl_pagesize) = *((size_t *) array[DL_PAGESIZE]); +} + +#else + +static void *variables[] = +{ + &GLRO(dl_pagesize) +}; + +static void +_dl_unprotect_relro (struct link_map *l) +{ + ElfW(Addr) start = ((l->l_addr + l->l_relro_addr) + & ~(GLRO(dl_pagesize) - 1)); + ElfW(Addr) end = ((l->l_addr + l->l_relro_addr + l->l_relro_size) + & ~(GLRO(dl_pagesize) - 1)); + + if (start != end) + __mprotect ((void *) start, end - start, PROT_READ | PROT_WRITE); +} + +void +_dl_static_init (struct link_map *l) +{ + struct link_map *rtld_map = l; + struct r_scope_elem **scope; + const ElfW(Sym) *ref = NULL; + lookup_t loadbase; + void (*f) (void *[]); + size_t i; + + loadbase = _dl_lookup_symbol_x ("_dl_var_init", l, &ref, l->l_local_scope, + NULL, 0, 1, NULL); + + for (scope = l->l_local_scope; *scope != NULL; scope++) + for (i = 0; i < (*scope)->r_nlist; i++) + if ((*scope)->r_list[i] == loadbase) + { + rtld_map = (*scope)->r_list[i]; + break; + } + + if (ref != NULL) + { + f = (void (*) (void *[])) DL_SYMBOL_ADDRESS (loadbase, ref); + _dl_unprotect_relro (rtld_map); + f (variables); + _dl_protect_relro (rtld_map); + } +} + +#endif diff --git a/sysdeps/unix/sysv/linux/arc/ldsodefs.h b/sysdeps/unix/sysv/linux/arc/ldsodefs.h new file mode 100644 index 000000000000..9eef836168be --- /dev/null +++ b/sysdeps/unix/sysv/linux/arc/ldsodefs.h @@ -0,0 +1,32 @@ +/* Run-time dynamic linker data structures for loaded ELF shared objects. ARC + Copyright (C) 2001-2020 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 + . */ + +#ifndef _LDSODEFS_H + +/* Get the real definitions. */ +#include_next + +/* Now define our stuff. */ + +/* We need special support to initialize DSO loaded for statically linked + binaries. */ +extern void _dl_static_init (struct link_map *map); +#undef DL_STATIC_INIT +#define DL_STATIC_INIT(map) _dl_static_init (map) + +#endif /* ldsodefs.h */