From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 1792) id 1520D3858D28; Tue, 11 Apr 2023 20:03:10 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 1520D3858D28 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sourceware.org; s=default; t=1681243390; bh=/ChqBPaa1pDc7tfnZlazvzShAs1Ji0/vb5Z86TgdSis=; h=From:To:Subject:Date:From; b=EOmPynXjEKEnK/U52VAIOGeBvYvbeJvEqJVffMX6Y6dkWEHIPkbVVCdTUhZsLedar C9MiK3tXABoJUqj4APzNjI95MC4CMrZ5BVVUKCrVuikcbpDw6HS4jKpPkPar+j5Kw7 HcWIuSGwVowzaZiyCoCnpGw6XwqsQUHf7CvbuGFA= Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit From: Samuel Thibault To: glibc-cvs@sourceware.org Subject: [glibc] Revert "hurd: Only check for TLS initialization inside rtld or in static builds" X-Act-Checkin: glibc X-Git-Author: Samuel Thibault X-Git-Refname: refs/heads/master X-Git-Oldrev: cd019ddd892e182277fadd6aedccc57fa3923c8d X-Git-Newrev: 5473a1747a7bd10a7a271c7e01e942711a707bb8 Message-Id: <20230411200310.1520D3858D28@sourceware.org> Date: Tue, 11 Apr 2023 20:03:10 +0000 (GMT) List-Id: https://sourceware.org/git/gitweb.cgi?p=glibc.git;h=5473a1747a7bd10a7a271c7e01e942711a707bb8 commit 5473a1747a7bd10a7a271c7e01e942711a707bb8 Author: Samuel Thibault Date: Tue Apr 11 18:06:03 2023 +0000 Revert "hurd: Only check for TLS initialization inside rtld or in static builds" This reverts commit b37899d34d2190ef4b454283188f22519f096048. Apparently we load libc.so (and thus start using its functions) before calling TLS_INIT_TP, so libc.so functions should not actually assume that TLS is always set up. Diff: --- sysdeps/mach/hurd/Makefile | 4 --- sysdeps/mach/hurd/i386/dl-tls-initialized.c | 21 ------------- sysdeps/mach/hurd/i386/tls.h | 43 +++++++++++---------------- sysdeps/mach/hurd/x86/init-first.c | 11 ++++++- sysdeps/mach/hurd/x86_64/dl-tls-initialized.c | 21 ------------- sysdeps/mach/hurd/x86_64/tls.h | 16 ++++------ 6 files changed, 33 insertions(+), 83 deletions(-) diff --git a/sysdeps/mach/hurd/Makefile b/sysdeps/mach/hurd/Makefile index f43e92bab3..d5584930a1 100644 --- a/sysdeps/mach/hurd/Makefile +++ b/sysdeps/mach/hurd/Makefile @@ -197,10 +197,6 @@ ifeq (hurd, $(subdir)) sysdep_routines += cthreads endif -ifeq (elf, $(subdir)) -sysdep-dl-routines += dl-tls-initialized -endif - ifeq (io, $(subdir)) sysdep_routines += f_setlk close_nocancel close_nocancel_nostatus \ fcntl_nocancel open_nocancel openat_nocancel read_nocancel \ diff --git a/sysdeps/mach/hurd/i386/dl-tls-initialized.c b/sysdeps/mach/hurd/i386/dl-tls-initialized.c deleted file mode 100644 index 493ec2396c..0000000000 --- a/sysdeps/mach/hurd/i386/dl-tls-initialized.c +++ /dev/null @@ -1,21 +0,0 @@ -/* Determine whether TLS is initialized, for i386/Hurd. - Copyright (C) 1995-2023 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 SHARED -unsigned short __init1_desc; -#endif diff --git a/sysdeps/mach/hurd/i386/tls.h b/sysdeps/mach/hurd/i386/tls.h index 0ac8917a95..694be9fd64 100644 --- a/sysdeps/mach/hurd/i386/tls.h +++ b/sysdeps/mach/hurd/i386/tls.h @@ -69,6 +69,18 @@ _Static_assert (offsetof (tcbhead_t, __private_ss) == 0x30, | (desc->high_word & 0xff000000)); \ }) +/* Return 1 if TLS is not initialized yet. */ +#ifndef SHARED +extern unsigned short __init1_desc; +#define __HURD_DESC_INITIAL(gs, ds) ((gs) == (ds) || (gs) == __init1_desc) +#else +#define __HURD_DESC_INITIAL(gs, ds) ((gs) == (ds)) +#endif + +#define __LIBC_NO_TLS() \ + ({ unsigned short ds, gs; \ + asm ("movw %%ds,%w0; movw %%gs,%w1" : "=q" (ds), "=q" (gs)); \ + __builtin_expect(__HURD_DESC_INITIAL(gs, ds), 0); }) #endif /* The TCB can have any size and the memory following the address the @@ -113,28 +125,6 @@ _Static_assert (offsetof (tcbhead_t, __private_ss) == 0x30, # define HURD_SEL_LDT(sel) (__builtin_expect ((sel) & 4, 0)) -#ifndef SHARED -extern unsigned short __init1_desc; -# define __HURD_DESC_INITIAL(gs, ds) ((gs) == (ds) || (gs) == __init1_desc) -#else -# define __HURD_DESC_INITIAL(gs, ds) ((gs) == (ds)) -#endif - -#if !defined (SHARED) || IS_IN (rtld) -/* Return 1 if TLS is not initialized yet. */ -extern inline bool __attribute__ ((unused)) -__LIBC_NO_TLS (void) -{ - unsigned short ds, gs; - asm ("movw %%ds, %w0\n" - "movw %%gs, %w1" - : "=q" (ds), "=q" (gs)); - return __glibc_unlikely (__HURD_DESC_INITIAL (gs, ds)); -} - -/* Code to initially initialize the thread pointer. This might need - special attention since 'errno' is not yet available and if the - operation can cause a failure 'errno' must not be touched. */ static inline bool __attribute__ ((unused)) _hurd_tls_init (tcbhead_t *tcb) { @@ -183,10 +173,11 @@ out: return success; } -# define TLS_INIT_TP(descr) _hurd_tls_init ((tcbhead_t *) (descr)) -#else /* defined (SHARED) && !IS_IN (rtld) */ -# define __LIBC_NO_TLS() 0 -#endif +/* Code to initially initialize the thread pointer. This might need + special attention since 'errno' is not yet available and if the + operation can cause a failure 'errno' must not be touched. */ +# define TLS_INIT_TP(descr) \ + _hurd_tls_init ((tcbhead_t *) (descr)) # if __GNUC_PREREQ (6, 0) diff --git a/sysdeps/mach/hurd/x86/init-first.c b/sysdeps/mach/hurd/x86/init-first.c index 89a5f44cdd..48c330ec06 100644 --- a/sysdeps/mach/hurd/x86/init-first.c +++ b/sysdeps/mach/hurd/x86/init-first.c @@ -40,6 +40,13 @@ extern char **_dl_argv; #ifndef SHARED static tcbhead_t __init1_tcbhead; +# ifndef __x86_64__ +unsigned short __init1_desc; +# endif +#endif + +#ifdef __x86_64__ +unsigned char __libc_tls_initialized; #endif /* Things that want to be run before _hurd_init or much anything else. @@ -159,7 +166,9 @@ first_init (void) _hurd_tls_init (&__init1_tcbhead); /* Make sure __LIBC_NO_TLS () keeps evaluating to 1. */ -# ifndef __x86_64__ +# ifdef __x86_64__ + __libc_tls_initialized = 0; +# else asm ("movw %%gs,%w0" : "=m" (__init1_desc)); # endif #endif diff --git a/sysdeps/mach/hurd/x86_64/dl-tls-initialized.c b/sysdeps/mach/hurd/x86_64/dl-tls-initialized.c deleted file mode 100644 index d0766f955d..0000000000 --- a/sysdeps/mach/hurd/x86_64/dl-tls-initialized.c +++ /dev/null @@ -1,21 +0,0 @@ -/* Determine whether TLS is initialized, for x86_64/Hurd. - Copyright (C) 1995-2023 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 - . */ - -#if !defined (SHARED) || IS_IN (rtld) -unsigned short __libc_tls_initialized; -#endif diff --git a/sysdeps/mach/hurd/x86_64/tls.h b/sysdeps/mach/hurd/x86_64/tls.h index 2b7135f635..e5c6f82acd 100644 --- a/sysdeps/mach/hurd/x86_64/tls.h +++ b/sysdeps/mach/hurd/x86_64/tls.h @@ -68,6 +68,10 @@ _Static_assert (offsetof (tcbhead_t, stack_guard) == 0x28, _Static_assert (offsetof (tcbhead_t, __private_ss) == 0x70, "split stack pointer offset"); +extern unsigned char __libc_tls_initialized; + +# define __LIBC_NO_TLS() __builtin_expect (!__libc_tls_initialized, 0) + /* The TCB can have any size and the memory following the address the thread pointer points to is unspecified. Allocate the TCB there. */ # define TLS_TCB_AT_TP 1 @@ -83,6 +87,8 @@ _Static_assert (offsetof (tcbhead_t, __private_ss) == 0x70, # define TCB_ALIGNMENT 64 +# define TLS_INIT_TP(descr) _hurd_tls_init ((tcbhead_t *) (descr)) + # define THREAD_SELF \ (*(tcbhead_t * __seg_fs *) offsetof (tcbhead_t, tcb)) /* Read member of the thread descriptor directly. */ @@ -168,10 +174,6 @@ _hurd_tls_new (thread_t child, tcbhead_t *tcb) i386_FSGS_BASE_STATE_COUNT); } -# if !defined (SHARED) || IS_IN (rtld) -extern unsigned char __libc_tls_initialized; -# define __LIBC_NO_TLS() __builtin_expect (!__libc_tls_initialized, 0) - static inline bool __attribute__ ((unused)) _hurd_tls_init (tcbhead_t *tcb) { @@ -195,12 +197,6 @@ _hurd_tls_init (tcbhead_t *tcb) return err == 0; } -# define TLS_INIT_TP(descr) _hurd_tls_init ((tcbhead_t *) (descr)) -# else /* defined (SHARED) && !IS_IN (rtld) */ -# define __LIBC_NO_TLS() 0 -# endif - - /* Global scope switch support. */ # define THREAD_GSCOPE_FLAG_UNUSED 0