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Subject[PATCH -mm] 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 !!!

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
---

fs/binfmt_elf.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

--- a/fs/binfmt_elf.c
+++ b/fs/binfmt_elf.c
@@ -704,12 +704,12 @@ static int load_elf_binary(struct linux_binprm *bprm)
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) {
@@ -1159,6 +1159,7 @@ static int load_elf_binary(struct linux_binprm *bprm)
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
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