[PATCH v4 05/27] x86: assembly, annotate local pseudo-functions

Jiri Slaby
2017-10-02T09:18:24Z

Use the newly added SYM_CODE_START_LOCAL* to annotate starts of all
pseudo-functions (those ending END) which do not have ".globl"
annotation. This is needed to balance END for tools that are about to
generate debuginfo. Note that we switch from END to SYM_CODE_END so that
everybody can see the pairing.

We are not annotating C-like functions (which handle frame ptr etc.)
here, hence we use SYM_CODE_* macros here, not SYM_FUNC_*. Note that
early_idt_handler_common already had ENDPROC -- switch that to
SYM_CODE_END for the same reason.

bogus_64_magic, bad_address, bad_get_user*, and bad_put_user are now
aligned, as they are separate functions. They do not mind to be aligned
-- no need to be compact there.

early_idt_handler_common is aligned now too, as it is after
early_idt_handler_array, so as well no need to be compact there.

verify_cpu is self-standing and included in other .S files, so align it
too.

The others have alignment preserved to what it used to be (using the
_NOALIGN variant of macros).

[v3] annotate more functions
[v4] describe the alignments changes

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: <x86@kernel.org>
---
arch/x86/entry/entry_32.S | 5 ++---
arch/x86/entry/entry_64.S | 3 ++-
arch/x86/kernel/acpi/wakeup_64.S | 3 ++-
arch/x86/kernel/head_32.S | 4 ++--
arch/x86/kernel/head_64.S | 4 ++--
arch/x86/kernel/verify_cpu.S | 4 ++--
arch/x86/lib/getuser.S | 8 ++++----
arch/x86/lib/putuser.S | 4 ++--
8 files changed, 18 insertions(+), 17 deletions(-)

diff --git a/arch/x86/entry/entry_32.S b/arch/x86/entry/entry_32.S
index 8a13d468635a..ee6e204bfac3 100644
--- a/arch/x86/entry/entry_32.S
+++ b/arch/x86/entry/entry_32.S
@@ -307,8 +307,7 @@ END(ret_from_fork)
*/

# userspace resumption stub bypassing syscall exit tracing
- ALIGN
-ret_from_exception:
+SYM_CODE_START_LOCAL(ret_from_exception)
preempt_stop(CLBR_ANY)
ret_from_intr:
#ifdef CONFIG_VM86
@@ -331,7 +330,7 @@ ENTRY(resume_userspace)
movl %esp, %eax
call prepare_exit_to_usermode
jmp restore_all
-END(ret_from_exception)
+SYM_CODE_END(ret_from_exception)

#ifdef CONFIG_PREEMPT
ENTRY(resume_kernel)
diff --git a/arch/x86/entry/entry_64.S b/arch/x86/entry/entry_64.S
index 49167258d587..c7cd02cf710b 100644
--- a/arch/x86/entry/entry_64.S
+++ b/arch/x86/entry/entry_64.S
@@ -936,7 +936,7 @@ EXPORT_SYMBOL(native_load_gs_index)
_ASM_EXTABLE(.Lgs_change, bad_gs)
.section .fixup, "ax"
/* running with kernelgs */
-bad_gs:
+SYM_CODE_START_LOCAL_NOALIGN(bad_gs)
SWAPGS /* switch back to user gs */
.macro ZAP_GS
/* This can't be a string because the preprocessor needs to see it. */
@@ -947,6 +947,7 @@ bad_gs:
xorl %eax, %eax
movl %eax, %gs
jmp 2b
+SYM_CODE_END(bad_gs)
.previous

/* Call softirq on interrupt stack. Interrupts are off. */
diff --git a/arch/x86/kernel/acpi/wakeup_64.S b/arch/x86/kernel/acpi/wakeup_64.S
index d0dd131a3e7e..987ef3d3aaf4 100644
--- a/arch/x86/kernel/acpi/wakeup_64.S
+++ b/arch/x86/kernel/acpi/wakeup_64.S
@@ -36,8 +36,9 @@ ENTRY(wakeup_long64)
jmp *%rax
ENDPROC(wakeup_long64)

-bogus_64_magic:
+SYM_CODE_START_LOCAL(bogus_64_magic)
jmp bogus_64_magic
+SYM_CODE_END(bogus_64_magic)

ENTRY(do_suspend_lowlevel)
FRAME_BEGIN
diff --git a/arch/x86/kernel/head_32.S b/arch/x86/kernel/head_32.S
index 519ac5824a24..bcf07134a31e 100644
--- a/arch/x86/kernel/head_32.S
+++ b/arch/x86/kernel/head_32.S
@@ -411,7 +411,7 @@ ENTRY(early_idt_handler_array)
.endr
ENDPROC(early_idt_handler_array)

-early_idt_handler_common:
+SYM_CODE_START_LOCAL(early_idt_handler_common)
/*
* The stack is the hardware frame, an error code or zero, and the
* vector number.
@@ -462,7 +462,7 @@ early_idt_handler_common:
decl %ss:early_recursion_flag
addl $4, %esp /* pop pt_regs->orig_ax */
iret
-ENDPROC(early_idt_handler_common)
+SYM_CODE_END(early_idt_handler_common)

/* This is the default interrupt "handler" :-) */
ENTRY(early_ignore_irq)
diff --git a/arch/x86/kernel/head_64.S b/arch/x86/kernel/head_64.S
index 63d17412e210..a2668b2ced90 100644
--- a/arch/x86/kernel/head_64.S
+++ b/arch/x86/kernel/head_64.S
@@ -288,7 +288,7 @@ ENTRY(early_idt_handler_array)
UNWIND_HINT_IRET_REGS offset=16
END(early_idt_handler_array)

-early_idt_handler_common:
+SYM_CODE_START_LOCAL(early_idt_handler_common)
/*
* The stack is the hardware frame, an error code or zero, and the
* vector number.
@@ -330,7 +330,7 @@ early_idt_handler_common:
20:
decl early_recursion_flag(%rip)
jmp restore_regs_and_iret
-END(early_idt_handler_common)
+SYM_CODE_END(early_idt_handler_common)

__INITDATA

diff --git a/arch/x86/kernel/verify_cpu.S b/arch/x86/kernel/verify_cpu.S
index 3d3c2f71f617..fd60f1ac5fec 100644
--- a/arch/x86/kernel/verify_cpu.S
+++ b/arch/x86/kernel/verify_cpu.S
@@ -33,7 +33,7 @@
#include <asm/cpufeatures.h>
#include <asm/msr-index.h>

-ENTRY(verify_cpu)
+SYM_FUNC_START_LOCAL(verify_cpu)
pushf # Save caller passed flags
push $0 # Kill any dangerous flags
popf
@@ -139,4 +139,4 @@ ENTRY(verify_cpu)
popf # Restore caller passed flags
xorl %eax, %eax
ret
-ENDPROC(verify_cpu)
+SYM_FUNC_END(verify_cpu)
diff --git a/arch/x86/lib/getuser.S b/arch/x86/lib/getuser.S
index 37b62d412148..e7473bf036cf 100644
--- a/arch/x86/lib/getuser.S
+++ b/arch/x86/lib/getuser.S
@@ -104,21 +104,21 @@ ENDPROC(__get_user_8)
EXPORT_SYMBOL(__get_user_8)

-bad_get_user:
+SYM_CODE_START_LOCAL(bad_get_user)
xor %edx,%edx
mov $(-EFAULT),%_ASM_AX
ASM_CLAC
ret
-END(bad_get_user)
+SYM_CODE_END(bad_get_user)

#ifdef CONFIG_X86_32
-bad_get_user_8:
+SYM_CODE_START_LOCAL(bad_get_user_8)
xor %edx,%edx
xor %ecx,%ecx
mov $(-EFAULT),%_ASM_AX
ASM_CLAC
ret
-END(bad_get_user_8)
+SYM_CODE_END(bad_get_user_8)
#endif

_ASM_EXTABLE(1b,bad_get_user)
diff --git a/arch/x86/lib/putuser.S b/arch/x86/lib/putuser.S
index cd5d716d2897..bccc98d8f57c 100644
--- a/arch/x86/lib/putuser.S
+++ b/arch/x86/lib/putuser.S
@@ -88,10 +88,10 @@ ENTRY(__put_user_8)
ENDPROC(__put_user_8)
EXPORT_SYMBOL(__put_user_8)

-bad_put_user:
+SYM_CODE_START_LOCAL(bad_put_user)
movl $-EFAULT,%eax
EXIT
-END(bad_put_user)
+SYM_CODE_END(bad_put_user)

_ASM_EXTABLE(1b,bad_put_user)
_ASM_EXTABLE(2b,bad_put_user)
--
2.14.2