29434801e7
Once upon a time, vdso2c aggressively stripped data from the vDSO
image when generating the final userspace image. This included
stripping the .altinstructions and .altinstr_replacement sections.
Eventually, the stripping process reverted to "objdump -S" and no
longer removed the aforementioned sections, but the comment remained.
Keeping the .alt* sections at the end of the PT_LOAD segment is no
longer necessary, but there's no harm in doing so and it's a helpful
reminder that they don't need to be included in the final vDSO image,
i.e. someone may want to take another stab at zapping/stripping the
unneeded sections.
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Acked-by: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@surriel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: da861e18ec ("x86, vdso: Get rid of the fake section mechanism")
Link: http://lkml.kernel.org/r/20181204212600.28090-3-sean.j.christopherson@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
94 lines
2.2 KiB
ArmAsm
94 lines
2.2 KiB
ArmAsm
/* SPDX-License-Identifier: GPL-2.0 */
|
|
#include <asm/vdso.h>
|
|
|
|
/*
|
|
* Linker script for vDSO. This is an ELF shared object prelinked to
|
|
* its virtual address, and with only one read-only segment.
|
|
* This script controls its layout.
|
|
*/
|
|
|
|
SECTIONS
|
|
{
|
|
/*
|
|
* User/kernel shared data is before the vDSO. This may be a little
|
|
* uglier than putting it after the vDSO, but it avoids issues with
|
|
* non-allocatable things that dangle past the end of the PT_LOAD
|
|
* segment.
|
|
*/
|
|
|
|
vvar_start = . - 3 * PAGE_SIZE;
|
|
vvar_page = vvar_start;
|
|
|
|
/* Place all vvars at the offsets in asm/vvar.h. */
|
|
#define EMIT_VVAR(name, offset) vvar_ ## name = vvar_page + offset;
|
|
#define __VVAR_KERNEL_LDS
|
|
#include <asm/vvar.h>
|
|
#undef __VVAR_KERNEL_LDS
|
|
#undef EMIT_VVAR
|
|
|
|
pvclock_page = vvar_start + PAGE_SIZE;
|
|
hvclock_page = vvar_start + 2 * PAGE_SIZE;
|
|
|
|
. = 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*)
|
|
*(.data*)
|
|
*(.sdata*)
|
|
*(.got.plt) *(.got)
|
|
*(.gnu.linkonce.d.*)
|
|
*(.bss*)
|
|
*(.dynbss*)
|
|
*(.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.
|
|
*/
|
|
|
|
.text : { *(.text*) } :text =0x90909090,
|
|
|
|
.altinstructions : { *(.altinstructions) } :text
|
|
.altinstr_replacement : { *(.altinstr_replacement) } :text
|
|
|
|
/DISCARD/ : {
|
|
*(.discard)
|
|
*(.discard.*)
|
|
*(__bug_table)
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Very old versions of ld do not recognize this name token; use the constant.
|
|
*/
|
|
#define PT_GNU_EH_FRAME 0x6474e550
|
|
|
|
/*
|
|
* 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;
|
|
}
|