lkml.org 
[lkml]   [2020]   [May]   [5]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
From
Subject[patch V4 part 2 01/18] x86/entry/64: Move non entry code into .text section
All ASM code which is not part of the entry functionality can move out into
the .text section. No reason to keep it in the non-instrumentable entry
section.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---
arch/x86/entry/entry_64.S | 10 ++++++++++
arch/x86/kernel/ftrace_64.S | 2 +-
2 files changed, 11 insertions(+), 1 deletion(-)

--- a/arch/x86/entry/entry_64.S
+++ b/arch/x86/entry/entry_64.S
@@ -279,6 +279,7 @@ SYM_CODE_END(entry_SYSCALL_64)
* %rdi: prev task
* %rsi: next task
*/
+.pushsection .text, "ax"
SYM_CODE_START(__switch_to_asm)
UNWIND_HINT_FUNC
/*
@@ -322,6 +323,7 @@ SYM_CODE_START(__switch_to_asm)

jmp __switch_to
SYM_CODE_END(__switch_to_asm)
+.popsection

/*
* A newly forked process directly context switches into this address.
@@ -330,6 +332,7 @@ SYM_CODE_END(__switch_to_asm)
* rbx: kernel thread func (NULL for user thread)
* r12: kernel thread arg
*/
+.pushsection .text, "ax"
SYM_CODE_START(ret_from_fork)
UNWIND_HINT_EMPTY
movq %rax, %rdi
@@ -358,6 +361,7 @@ SYM_CODE_START(ret_from_fork)
movq $0, RAX(%rsp)
jmp 2b
SYM_CODE_END(ret_from_fork)
+.popsection

/*
* Build the entry stubs with some assembler magic.
@@ -1042,6 +1046,7 @@ idtentry simd_coprocessor_error do_simd
* Reload gs selector with exception handling
* edi: new selector
*/
+.pushsection .text, "ax"
SYM_FUNC_START(native_load_gs_index)
FRAME_BEGIN
pushfq
@@ -1058,6 +1063,7 @@ SYM_FUNC_START(native_load_gs_index)
ret
SYM_FUNC_END(native_load_gs_index)
EXPORT_SYMBOL(native_load_gs_index)
+.popsection

_ASM_EXTABLE(.Lgs_change, .Lbad_gs)
.section .fixup, "ax"
@@ -1077,6 +1083,7 @@ SYM_CODE_END(.Lbad_gs)
.previous

/* Call softirq on interrupt stack. Interrupts are off. */
+.pushsection .text, "ax"
SYM_FUNC_START(do_softirq_own_stack)
pushq %rbp
mov %rsp, %rbp
@@ -1086,6 +1093,7 @@ SYM_FUNC_START(do_softirq_own_stack)
leaveq
ret
SYM_FUNC_END(do_softirq_own_stack)
+.popsection

#ifdef CONFIG_XEN_PV
idtentry hypervisor_callback xen_do_hypervisor_callback has_error_code=0
@@ -1730,6 +1738,7 @@ SYM_CODE_START(ignore_sysret)
SYM_CODE_END(ignore_sysret)
#endif

+.pushsection .text, "ax"
SYM_CODE_START(rewind_stack_do_exit)
UNWIND_HINT_FUNC
/* Prevent any naive code from trying to unwind to our caller. */
@@ -1741,3 +1750,4 @@ SYM_CODE_START(rewind_stack_do_exit)

call do_exit
SYM_CODE_END(rewind_stack_do_exit)
+.popsection
--- a/arch/x86/kernel/ftrace_64.S
+++ b/arch/x86/kernel/ftrace_64.S
@@ -12,7 +12,7 @@
#include <asm/frame.h>

.code64
- .section .entry.text, "ax"
+ .section .text, "ax"

#ifdef CONFIG_FRAME_POINTER
/* Save parent and function stack frames (rip and rbp) */
\
 
 \ /
  Last update: 2020-05-05 16:23    [W:0.314 / U:0.132 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site