[PATCH] x86/asm/entry/32: Rename labels in INT 0x80 code path

From: Denys Vlasenko
Date: Sun Jun 07 2015 - 14:42:11 EST


"ia32_syscall" label name (entry point for INT 80) is inconsistent with
"ia32_sysenter_target" (entry point for SYSENTER insn) and
"ia32_cstar_target" (entry point for SYSCALL insn).

It is especially misleading since we do have code in this file which
handles SYSCALL insn, and it's _not this code_.

Rename it to ia32_int80_target. Rename all internal labels in ia32_int80_target
routine to int80_<foo> form, similar to the convention in SYSENTER and SYSCALL
code blocks.

Not renaming ia32_cstar_target: even though "ia32_syscall_target" would make
a bit more sense, it's less greppable: "syscall" is a very common string.

Signed-off-by: Denys Vlasenko <dvlasenk@xxxxxxxxxx>
CC: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
CC: Steven Rostedt <rostedt@xxxxxxxxxxx>
CC: Ingo Molnar <mingo@xxxxxxxxxx>
CC: Borislav Petkov <bp@xxxxxxxxx>
CC: "H. Peter Anvin" <hpa@xxxxxxxxx>
CC: Andy Lutomirski <luto@xxxxxxxxxxxxxx>
CC: Oleg Nesterov <oleg@xxxxxxxxxx>
CC: Frederic Weisbecker <fweisbec@xxxxxxxxx>
CC: Alexei Starovoitov <ast@xxxxxxxxxxxx>
CC: Will Drewry <wad@xxxxxxxxxxxx>
CC: Kees Cook <keescook@xxxxxxxxxxxx>
CC: x86@xxxxxxxxxx
CC: linux-kernel@xxxxxxxxxxxxxxx
---
arch/x86/entry/entry_64_compat.S | 12 ++++++------
arch/x86/include/asm/proto.h | 2 +-
arch/x86/kernel/traps.c | 2 +-
3 files changed, 8 insertions(+), 8 deletions(-)

diff --git a/arch/x86/entry/entry_64_compat.S b/arch/x86/entry/entry_64_compat.S
index b80f8d4..744a3f7 100644
--- a/arch/x86/entry/entry_64_compat.S
+++ b/arch/x86/entry/entry_64_compat.S
@@ -443,7 +443,7 @@ ia32_ret_from_sys_call:
* Assumes it is only called from user space and entered with interrupts off.
*/

-ENTRY(ia32_syscall)
+ENTRY(ia32_int80_target)
/*
* Interrupts are off on entry.
* We do not frame this tiny irq-off block with TRACE_IRQS_OFF/ON,
@@ -472,9 +472,9 @@ ENTRY(ia32_syscall)

orl $TS_COMPAT, ASM_THREAD_INFO(TI_status, %rsp, SIZEOF_PTREGS)
testl $_TIF_WORK_SYSCALL_ENTRY, ASM_THREAD_INFO(TI_flags, %rsp, SIZEOF_PTREGS)
- jnz ia32_tracesys
+ jnz int80_tracesys

-ia32_do_call:
+int80_do_call:
/* 32-bit syscall -> 64-bit C ABI argument conversion */
movl %edi, %r8d /* arg5 */
movl %ebp, %r9d /* arg6 */
@@ -489,7 +489,7 @@ ia32_do_call:
1:
jmp int_ret_from_sys_call

-ia32_tracesys:
+int80_tracesys:
SAVE_EXTRA_REGS
movq %rsp, %rdi /* &pt_regs -> arg1 */
call syscall_trace_enter
@@ -506,8 +506,8 @@ ia32_tracesys:
movl RDI(%rsp), %edi
movl %eax, %eax /* zero extension */
RESTORE_EXTRA_REGS
- jmp ia32_do_call
-END(ia32_syscall)
+ jmp int80_do_call
+END(ia32_int80_target)

.macro PTREGSCALL label, func
ALIGN
diff --git a/arch/x86/include/asm/proto.h b/arch/x86/include/asm/proto.h
index a90f897..3c692be 100644
--- a/arch/x86/include/asm/proto.h
+++ b/arch/x86/include/asm/proto.h
@@ -8,7 +8,7 @@
void system_call(void);
void syscall_init(void);

-void ia32_syscall(void);
+void ia32_int80_target(void);
void ia32_cstar_target(void);
void ia32_sysenter_target(void);

diff --git a/arch/x86/kernel/traps.c b/arch/x86/kernel/traps.c
index b5e7687..b8a4204 100644
--- a/arch/x86/kernel/traps.c
+++ b/arch/x86/kernel/traps.c
@@ -894,7 +894,7 @@ void __init trap_init(void)
set_bit(i, used_vectors);

#ifdef CONFIG_IA32_EMULATION
- set_system_intr_gate(IA32_SYSCALL_VECTOR, ia32_syscall);
+ set_system_intr_gate(IA32_SYSCALL_VECTOR, ia32_int80_target);
set_bit(IA32_SYSCALL_VECTOR, used_vectors);
#endif

--
1.8.1.4

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