The patch titled
Subject: elf: init pt_regs pointer later
has been added to the -mm tree. Its filename is
elf-init-pt_regs-pointer-later.patch
This patch should soon appear at
http://ozlabs.org/~akpm/mmots/broken-out/elf-init-pt_regs-pointer-later.patch
and later at
http://ozlabs.org/~akpm/mmotm/broken-out/elf-init-pt_regs-pointer-later.patch
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*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***
The -mm tree is included into linux-next and is updated
there every 3-4 working days
------------------------------------------------------
From: Alexey Dobriyan <adobriyan@xxxxxxxxx>
Subject: elf: init pt_regs pointer later
Get "current_pt_regs" pointer right before usage.
Space savings on x86_64:
add/remove: 0/0 grow/shrink: 0/1 up/down: 0/-180 (-180)
Function old new delta
load_elf_binary 5806 5626 -180 !!!
Link: http://lkml.kernel.org/r/20190419200343.GA19788@avx2
Signed-off-by: Alexey Dobriyan <adobriyan@xxxxxxxxx>
Tested-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
fs/binfmt_elf.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
--- a/fs/binfmt_elf.c~elf-init-pt_regs-pointer-later
+++ a/fs/binfmt_elf.c
@@ -704,12 +704,12 @@ static int load_elf_binary(struct linux_
unsigned long start_code, end_code, start_data, end_data;
unsigned long reloc_func_desc __maybe_unused = 0;
int executable_stack = EXSTACK_DEFAULT;
- struct pt_regs *regs = current_pt_regs();
struct {
struct elfhdr elf_ex;
struct elfhdr interp_elf_ex;
} *loc;
struct arch_elf_state arch_state = INIT_ARCH_ELF_STATE;
+ struct pt_regs *regs;
loc = kmalloc(sizeof(*loc), GFP_KERNEL);
if (!loc) {
@@ -1150,6 +1150,7 @@ out_free_interp:
MAP_FIXED | MAP_PRIVATE, 0);
}
+ regs = current_pt_regs();
#ifdef ELF_PLAT_INIT
/*
* The ABI may specify that certain registers be set up in special
_
Patches currently in -mm which might be from adobriyan@xxxxxxxxx are
ramfs-support-o_tmpfile.patch
elf-make-scope-of-pos-variable-smaller.patch
elf-free-pt_interp-filename-asap.patch
elf-delete-trailing-return-in-functions-returning-void.patch
elf-save-1-indent-level.patch
elf-move-variables-initialization-closer-to-their-usage.patch
elf-extract-prot_-calculations.patch
elf-init-pt_regs-pointer-later.patch
exec-move-recursion_depth-out-of-critical-sections.patch
