linux-loongson/arch/riscv/kernel/vdso/vdso.lds.S
Fangrui Song e0eb1b6b0c
riscv: vdso: Exclude .rodata from the PT_DYNAMIC segment
.rodata is implicitly included in the PT_DYNAMIC segment due to
inheriting the segment of the preceding .dynamic section (in both GNU ld
and LLD).  When the .rodata section's size is not a multiple of 16
bytes on riscv64, llvm-readelf will report a "PT_DYNAMIC dynamic table
is invalid" warning.  Note: in the presence of the .dynamic section, GNU
readelf and llvm-readelf's -d option decodes the dynamic section using
the section.

This issue arose after commit 8f8c1ff879
("riscv: vdso.lds.S: remove hardcoded 0x800 .text start addr"), which
placed .rodata directly after .dynamic by removing .eh_frame.

This patch resolves the implicit inclusion into PT_DYNAMIC by explicitly
specifying the :text output section phdr.

Reported-by: Nathan Chancellor <nathan@kernel.org>
Closes: https://github.com/ClangBuiltLinux/linux/issues/2093
Signed-off-by: Fangrui Song <i@maskray.me>
Tested-by: Nathan Chancellor <nathan@kernel.org>
Link: https://lore.kernel.org/r/20250602-riscv-vdso-v1-1-0620cf63cff0@maskray.me
Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
2025-06-10 13:06:48 -07:00

89 lines
1.8 KiB
ArmAsm

/* SPDX-License-Identifier: GPL-2.0-only */
/*
* Copyright (C) 2012 Regents of the University of California
*/
#include <asm/page.h>
#include <asm/vdso.h>
#include <vdso/datapage.h>
OUTPUT_ARCH(riscv)
SECTIONS
{
VDSO_VVAR_SYMS
. = 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) }
.dynamic : { *(.dynamic) } :text :dynamic
.rodata : {
*(.rodata .rodata.* .gnu.linkonce.r.*)
*(.got.plt) *(.got)
*(.data .data.* .gnu.linkonce.d.*)
*(.dynbss)
*(.bss .bss.* .gnu.linkonce.b.*)
} :text
.note : { *(.note.*) } :text :note
.eh_frame_hdr : { *(.eh_frame_hdr) } :text :eh_frame_hdr
.eh_frame : { KEEP (*(.eh_frame)) } :text
/*
* Text is well-separated from actual data: there's plenty of
* stuff that isn't used at runtime in between.
*/
. = ALIGN(16);
.text : { *(.text .text.*) } :text
. = ALIGN(4);
.alternative : {
*(.alternative)
}
}
/*
* 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 */
eh_frame_hdr PT_GNU_EH_FRAME;
}
/*
* This controls what symbols we export from the DSO.
*/
VERSION
{
LINUX_4.15 {
global:
__vdso_rt_sigreturn;
#ifdef HAS_VGETTIMEOFDAY
__vdso_gettimeofday;
__vdso_clock_gettime;
__vdso_clock_getres;
#endif
__vdso_getcpu;
__vdso_flush_icache;
#ifndef COMPAT_VDSO
__vdso_riscv_hwprobe;
#endif
#if defined(CONFIG_VDSO_GETRANDOM) && !defined(COMPAT_VDSO)
__vdso_getrandom;
#endif
local: *;
};
}