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linux/arch/arm64/kernel/vdso/vdso.lds.S

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treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 234 Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation this program 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 general public license for more details you should have received a copy of the gnu general public license along with this program if not see http www gnu org licenses extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 503 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Alexios Zavras <alexios.zavras@intel.com> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Enrico Weigelt <info@metux.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190602204653.811534538@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-03 08:44:50 +03:00
/* SPDX-License-Identifier: GPL-2.0-only */
arm64: VDSO support This patch adds VDSO support for 64-bit applications. The VDSO code is currently used for sys_rt_sigreturn() and optimised gettimeofday() (using the user-accessible generic counter). Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Tony Lindgren <tony@atomide.com> Acked-by: Nicolas Pitre <nico@linaro.org> Acked-by: Olof Johansson <olof@lixom.net> Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com> Acked-by: Arnd Bergmann <arnd@arndb.de>
2012-03-05 15:49:31 +04:00
/*
* GNU linker script for the VDSO library.
*
* Copyright (C) 2012 ARM Limited
*
* Author: Will Deacon <will.deacon@arm.com>
* Heavily based on the vDSO linker scripts for other archs.
*/
#include <linux/const.h>
#include <asm/page.h>
#include <asm/vdso.h>
arm64: vdso: put ELF related sections in the linker script Use macros from vmlinux.lds.h to explicitly name sections that are included in the VDSO output. Signed-off-by: Joey Gouly <joey.gouly@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org> Cc: Masahiro Yamada <masahiroy@kernel.org> Cc: Vincenzo Frascino <vincenzo.frascino@arm.com> Cc: Kees Cook <keescook@chromium.org> Reviewed-by: Kees Cook <keescook@chromium.org> Reviewed-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Link: https://lore.kernel.org/r/20220510095834.32394-2-joey.gouly@arm.com Signed-off-by: Will Deacon <will@kernel.org>
2022-05-10 12:58:31 +03:00
#include <asm-generic/vmlinux.lds.h>
arm64: VDSO support This patch adds VDSO support for 64-bit applications. The VDSO code is currently used for sys_rt_sigreturn() and optimised gettimeofday() (using the user-accessible generic counter). Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Tony Lindgren <tony@atomide.com> Acked-by: Nicolas Pitre <nico@linaro.org> Acked-by: Olof Johansson <olof@lixom.net> Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com> Acked-by: Arnd Bergmann <arnd@arndb.de>
2012-03-05 15:49:31 +04:00
OUTPUT_FORMAT("elf64-littleaarch64", "elf64-bigaarch64", "elf64-littleaarch64")
OUTPUT_ARCH(aarch64)
SECTIONS
{
arm64/vdso: Add time namespace page Allocate the time namespace page among VVAR pages. Provide __arch_get_timens_vdso_data() helper for VDSO code to get the code-relative position of VVARs on that special page. If a task belongs to a time namespace then the VVAR page which contains the system wide VDSO data is replaced with a namespace specific page which has the same layout as the VVAR page. That page has vdso_data->seq set to 1 to enforce the slow path and vdso_data->clock_mode set to VCLOCK_TIMENS to enforce the time namespace handling path. The extra check in the case that vdso_data->seq is odd, e.g. a concurrent update of the VDSO data is in progress, is not really affecting regular tasks which are not part of a time namespace as the task is spin waiting for the update to finish and vdso_data->seq to become even again. If a time namespace task hits that code path, it invokes the corresponding time getter function which retrieves the real VVAR page, reads host time and then adds the offset for the requested clock which is stored in the special VVAR page. The time-namespace page isn't allocated on !CONFIG_TIME_NAMESPACE, but vma is the same size, which simplifies criu/vdso migration between different kernel configs. Signed-off-by: Andrei Vagin <avagin@gmail.com> Reviewed-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Reviewed-by: Dmitry Safonov <dima@arista.com> Cc: Mark Rutland <mark.rutland@arm.com> Link: https://lore.kernel.org/r/20200624083321.144975-4-avagin@gmail.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2020-06-24 11:33:18 +03:00
PROVIDE(_vdso_data = . - __VVAR_PAGES * PAGE_SIZE);
#ifdef CONFIG_TIME_NS
PROVIDE(_timens_data = _vdso_data + PAGE_SIZE);
#endif
arm64: VDSO support This patch adds VDSO support for 64-bit applications. The VDSO code is currently used for sys_rt_sigreturn() and optimised gettimeofday() (using the user-accessible generic counter). Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Tony Lindgren <tony@atomide.com> Acked-by: Nicolas Pitre <nico@linaro.org> Acked-by: Olof Johansson <olof@lixom.net> Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com> Acked-by: Arnd Bergmann <arnd@arndb.de>
2012-03-05 15:49:31 +04:00
. = VDSO_LBASE + SIZEOF_HEADERS;
.hash : { *(.hash) } :text
.gnu.hash : { *(.gnu.hash) }
.dynsym : { *(.dynsym) }
.dynstr : { *(.dynstr) }
.gnu.version : { *(.gnu.version) }
.gnu.version_d : { *(.gnu.version_d) }
.gnu.version_r : { *(.gnu.version_r) }
arm64/vdso: Discard .note.gnu.property sections in vDSO The arm64 assembler in binutils 2.32 and above generates a program property note in a note section, .note.gnu.property, to encode used x86 ISAs and features. But the kernel linker script only contains a single NOTE segment: PHDRS { text PT_LOAD FLAGS(5) FILEHDR PHDRS; /* PF_R|PF_X */ dynamic PT_DYNAMIC FLAGS(4); /* PF_R */ note PT_NOTE FLAGS(4); /* PF_R */ } The NOTE segment generated by the vDSO linker script is aligned to 4 bytes. But the .note.gnu.property section must be aligned to 8 bytes on arm64. $ readelf -n vdso64.so Displaying notes found in: .note Owner Data size Description Linux 0x00000004 Unknown note type: (0x00000000) description data: 06 00 00 00 readelf: Warning: note with invalid namesz and/or descsz found at offset 0x20 readelf: Warning: type: 0x78, namesize: 0x00000100, descsize: 0x756e694c, alignment: 8 Since the note.gnu.property section in the vDSO is not checked by the dynamic linker, discard the .note.gnu.property sections in the vDSO. Similar to commit 4caffe6a28d31 ("x86/vdso: Discard .note.gnu.property sections in vDSO"), but for arm64. Signed-off-by: Bill Wendling <morbo@google.com> Reviewed-by: Kees Cook <keescook@chromium.org> Acked-by: Ard Biesheuvel <ardb@kernel.org> Link: https://lore.kernel.org/r/20210423205159.830854-1-morbo@google.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2021-04-23 23:51:59 +03:00
/*
* Discard .note.gnu.property sections which are unused and have
* different alignment requirement from vDSO note sections.
*/
/DISCARD/ : {
*(.note.GNU-stack .note.gnu.property)
}
arm64: VDSO support This patch adds VDSO support for 64-bit applications. The VDSO code is currently used for sys_rt_sigreturn() and optimised gettimeofday() (using the user-accessible generic counter). Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Tony Lindgren <tony@atomide.com> Acked-by: Nicolas Pitre <nico@linaro.org> Acked-by: Olof Johansson <olof@lixom.net> Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com> Acked-by: Arnd Bergmann <arnd@arndb.de>
2012-03-05 15:49:31 +04:00
.note : { *(.note.*) } :text :note
. = ALIGN(16);
.text : { *(.text*) } :text =0xd503201f
PROVIDE (__etext = .);
PROVIDE (_etext = .);
PROVIDE (etext = .);
arm64: alternative: patch alternatives in the vDSO Make it possible to use alternatives in the vDSO, so that better implementations can be used if possible. Signed-off-by: Joey Gouly <joey.gouly@arm.com> Cc: Will Deacon <will@kernel.org> Cc: Vincenzo Frascino <vincenzo.frascino@arm.com> Cc: Mark Rutland <mark.rutland@arm.com> Acked-by: Mark Rutland <mark.rutland@arm.com> Link: https://lore.kernel.org/r/20220830104833.34636-3-joey.gouly@arm.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2022-08-30 13:48:32 +03:00
. = ALIGN(4);
.altinstructions : {
*(.altinstructions)
}
arm64: VDSO support This patch adds VDSO support for 64-bit applications. The VDSO code is currently used for sys_rt_sigreturn() and optimised gettimeofday() (using the user-accessible generic counter). Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Tony Lindgren <tony@atomide.com> Acked-by: Nicolas Pitre <nico@linaro.org> Acked-by: Olof Johansson <olof@lixom.net> Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com> Acked-by: Arnd Bergmann <arnd@arndb.de>
2012-03-05 15:49:31 +04:00
.dynamic : { *(.dynamic) } :text :dynamic
arm64: vdso: put ELF related sections in the linker script Use macros from vmlinux.lds.h to explicitly name sections that are included in the VDSO output. Signed-off-by: Joey Gouly <joey.gouly@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org> Cc: Masahiro Yamada <masahiroy@kernel.org> Cc: Vincenzo Frascino <vincenzo.frascino@arm.com> Cc: Kees Cook <keescook@chromium.org> Reviewed-by: Kees Cook <keescook@chromium.org> Reviewed-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Link: https://lore.kernel.org/r/20220510095834.32394-2-joey.gouly@arm.com Signed-off-by: Will Deacon <will@kernel.org>
2022-05-10 12:58:31 +03:00
.rela.dyn : ALIGN(8) { *(.rela .rela*) }
arm64: vdso*: place got/plt sections in .rodata The vDSO will not contain absolute relocations, so place these sections in .rodata. Signed-off-by: Joey Gouly <joey.gouly@arm.com> Link: https://lore.kernel.org/linux-arm-kernel/00abb0c5-6360-0004-353f-e7a88b3bd22c@arm.com/ Cc: Will Deacon <will@kernel.org> Cc: Vincenzo Frascino <vincenzo.frascino@arm.com> Link: https://lore.kernel.org/r/20220628151307.35561-3-joey.gouly@arm.com Signed-off-by: Will Deacon <will@kernel.org>
2022-06-28 18:13:07 +03:00
.rodata : {
*(.rodata*)
*(.got)
*(.got.plt)
arm64: vdso: put ELF related sections in the linker script Use macros from vmlinux.lds.h to explicitly name sections that are included in the VDSO output. Signed-off-by: Joey Gouly <joey.gouly@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org> Cc: Masahiro Yamada <masahiroy@kernel.org> Cc: Vincenzo Frascino <vincenzo.frascino@arm.com> Cc: Kees Cook <keescook@chromium.org> Reviewed-by: Kees Cook <keescook@chromium.org> Reviewed-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Link: https://lore.kernel.org/r/20220510095834.32394-2-joey.gouly@arm.com Signed-off-by: Will Deacon <will@kernel.org>
2022-05-10 12:58:31 +03:00
*(.plt)
*(.plt.*)
*(.iplt)
*(.igot .igot.plt)
arm64: vdso*: place got/plt sections in .rodata The vDSO will not contain absolute relocations, so place these sections in .rodata. Signed-off-by: Joey Gouly <joey.gouly@arm.com> Link: https://lore.kernel.org/linux-arm-kernel/00abb0c5-6360-0004-353f-e7a88b3bd22c@arm.com/ Cc: Will Deacon <will@kernel.org> Cc: Vincenzo Frascino <vincenzo.frascino@arm.com> Link: https://lore.kernel.org/r/20220628151307.35561-3-joey.gouly@arm.com Signed-off-by: Will Deacon <will@kernel.org>
2022-06-28 18:13:07 +03:00
} :text
arm64: VDSO support This patch adds VDSO support for 64-bit applications. The VDSO code is currently used for sys_rt_sigreturn() and optimised gettimeofday() (using the user-accessible generic counter). Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Tony Lindgren <tony@atomide.com> Acked-by: Nicolas Pitre <nico@linaro.org> Acked-by: Olof Johansson <olof@lixom.net> Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com> Acked-by: Arnd Bergmann <arnd@arndb.de>
2012-03-05 15:49:31 +04:00
_end = .;
PROVIDE(end = .);
arm64: vdso: put ELF related sections in the linker script Use macros from vmlinux.lds.h to explicitly name sections that are included in the VDSO output. Signed-off-by: Joey Gouly <joey.gouly@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org> Cc: Masahiro Yamada <masahiroy@kernel.org> Cc: Vincenzo Frascino <vincenzo.frascino@arm.com> Cc: Kees Cook <keescook@chromium.org> Reviewed-by: Kees Cook <keescook@chromium.org> Reviewed-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Link: https://lore.kernel.org/r/20220510095834.32394-2-joey.gouly@arm.com Signed-off-by: Will Deacon <will@kernel.org>
2022-05-10 12:58:31 +03:00
DWARF_DEBUG
ELF_DETAILS
arm64: VDSO support This patch adds VDSO support for 64-bit applications. The VDSO code is currently used for sys_rt_sigreturn() and optimised gettimeofday() (using the user-accessible generic counter). Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Tony Lindgren <tony@atomide.com> Acked-by: Nicolas Pitre <nico@linaro.org> Acked-by: Olof Johansson <olof@lixom.net> Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com> Acked-by: Arnd Bergmann <arnd@arndb.de>
2012-03-05 15:49:31 +04:00
/DISCARD/ : {
*(.data .data.* .gnu.linkonce.d.* .sdata*)
*(.bss .sbss .dynbss .dynsbss)
arm64: vdso: disable .eh_frame_hdr via /DISCARD/ instead of --no-eh-frame-hdr Currently with ld.lld we emit an empty .eh_frame_hdr section (and a corresponding program header) into the vDSO. With ld.bfd the section is not emitted but the program header is, with p_vaddr set to 0. This can lead to unwinders attempting to interpret the data at whichever location the program header happens to point to as an unwind info header. This happens to be mostly harmless as long as the byte at that location (interpreted as a version number) has a value other than 1, causing both libgcc and LLVM libunwind to ignore the section (in libunwind's case, after printing an error message to stderr), but it could lead to worse problems if the byte happened to be 1 or the program header points to non-readable memory (e.g. if the empty section was placed at a page boundary). Instead of disabling .eh_frame_hdr via --no-eh-frame-hdr (which also has the downside of being unsupported by older versions of GNU binutils), disable it by discarding the section, and stop emitting the program header that points to it. I understand that we intend to emit valid unwind info for the vDSO at some point. Once that happens this patch can be reverted. Signed-off-by: Peter Collingbourne <pcc@google.com> Acked-by: Ard Biesheuvel <ardb@kernel.org> Acked-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Link: https://linux-review.googlesource.com/id/If745fd9cadcb31b4010acbf5693727fe111b0863 Link: https://lore.kernel.org/r/20201230221954.2007257-1-pcc@google.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2020-12-31 01:19:54 +03:00
*(.eh_frame .eh_frame_hdr)
arm64: VDSO support This patch adds VDSO support for 64-bit applications. The VDSO code is currently used for sys_rt_sigreturn() and optimised gettimeofday() (using the user-accessible generic counter). Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Tony Lindgren <tony@atomide.com> Acked-by: Nicolas Pitre <nico@linaro.org> Acked-by: Olof Johansson <olof@lixom.net> Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com> Acked-by: Arnd Bergmann <arnd@arndb.de>
2012-03-05 15:49:31 +04:00
}
}
/*
* We must supply the ELF program headers explicitly to get just one
* PT_LOAD segment, and set the flags explicitly to make segments read-only.
*/
PHDRS
{
text PT_LOAD FLAGS(5) FILEHDR PHDRS; /* PF_R|PF_X */
dynamic PT_DYNAMIC FLAGS(4); /* PF_R */
note PT_NOTE FLAGS(4); /* PF_R */
}
/*
* This controls what symbols we export from the DSO.
*/
VERSION
{
LINUX_2.6.39 {
global:
__kernel_rt_sigreturn;
__kernel_gettimeofday;
__kernel_clock_gettime;
__kernel_clock_getres;
local: *;
};
}
/*
* Make the sigreturn code visible to the kernel.
*/
VDSO_sigtramp = __kernel_rt_sigreturn;
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