x86/asm/entry: Untangle 'ia32_sysenter_target' into two entry points: entry_SYSENTER_32 and entry_SYSENTER_compat
So the SYSENTER instruction is pretty quirky and it has different behavior
depending on bitness and CPU maker.
Yet we create a false sense of coherency by naming it 'ia32_sysenter_target'
in both of the cases.
Split the name into its two uses:
ia32_sysenter_target (32) -> entry_SYSENTER_32
ia32_sysenter_target (64) -> entry_SYSENTER_compat
As per the generic naming scheme for x86 system call entry points:
entry_MNEMONIC_qualifier
where 'qualifier' is one of _32, _64 or _compat.
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
diff --git a/arch/x86/entry/entry_32.S b/arch/x86/entry/entry_32.S
index 0ac73de..a65f46c 100644
--- a/arch/x86/entry/entry_32.S
+++ b/arch/x86/entry/entry_32.S
@@ -307,7 +307,7 @@
the vsyscall page. See vsyscall-sysentry.S, which defines the symbol. */
# sysenter call handler stub
-ENTRY(ia32_sysenter_target)
+ENTRY(entry_SYSENTER_32)
movl TSS_sysenter_sp0(%esp),%esp
sysenter_past_esp:
/*
@@ -412,7 +412,7 @@
.popsection
_ASM_EXTABLE(1b,2b)
PTGS_TO_GS_EX
-ENDPROC(ia32_sysenter_target)
+ENDPROC(entry_SYSENTER_32)
# system call handler stub
ENTRY(system_call)
@@ -1135,7 +1135,7 @@
ENTRY(debug)
ASM_CLAC
- cmpl $ia32_sysenter_target,(%esp)
+ cmpl $entry_SYSENTER_32,(%esp)
jne debug_stack_correct
FIX_STACK 12, debug_stack_correct, debug_esp_fix_insn
debug_stack_correct:
@@ -1165,7 +1165,7 @@
popl %eax
je nmi_espfix_stack
#endif
- cmpl $ia32_sysenter_target,(%esp)
+ cmpl $entry_SYSENTER_32,(%esp)
je nmi_stack_fixup
pushl %eax
movl %esp,%eax
@@ -1176,7 +1176,7 @@
cmpl $(THREAD_SIZE-20),%eax
popl %eax
jae nmi_stack_correct
- cmpl $ia32_sysenter_target,12(%esp)
+ cmpl $entry_SYSENTER_32,12(%esp)
je nmi_debug_stack_check
nmi_stack_correct:
pushl %eax
diff --git a/arch/x86/entry/entry_64_compat.S b/arch/x86/entry/entry_64_compat.S
index 8058892..59840e3 100644
--- a/arch/x86/entry/entry_64_compat.S
+++ b/arch/x86/entry/entry_64_compat.S
@@ -57,7 +57,7 @@
* path below. We set up a complete hardware stack frame to share code
* with the int 0x80 path.
*/
-ENTRY(ia32_sysenter_target)
+ENTRY(entry_SYSENTER_compat)
/*
* Interrupts are off on entry.
* We do not frame this tiny irq-off block with TRACE_IRQS_OFF/ON,
@@ -256,7 +256,7 @@
RESTORE_EXTRA_REGS
jmp sysenter_do_call
-ENDPROC(ia32_sysenter_target)
+ENDPROC(entry_SYSENTER_compat)
/*
* 32-bit SYSCALL instruction entry.
diff --git a/arch/x86/include/asm/proto.h b/arch/x86/include/asm/proto.h
index 7d2961a..83a7f82 100644
--- a/arch/x86/include/asm/proto.h
+++ b/arch/x86/include/asm/proto.h
@@ -10,7 +10,8 @@
void entry_INT80_compat(void);
void entry_SYSCALL_compat(void);
-void ia32_sysenter_target(void);
+void entry_SYSENTER_32(void);
+void entry_SYSENTER_compat(void);
void x86_configure_nx(void);
void x86_report_nx(void);
diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
index f0b85c4..b2ae7ce 100644
--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -1026,7 +1026,7 @@
(unsigned long)tss + offsetofend(struct tss_struct, SYSENTER_stack),
0);
- wrmsr(MSR_IA32_SYSENTER_EIP, (unsigned long)ia32_sysenter_target, 0);
+ wrmsr(MSR_IA32_SYSENTER_EIP, (unsigned long)entry_SYSENTER_32, 0);
out:
put_cpu();
@@ -1216,7 +1216,7 @@
*/
wrmsrl_safe(MSR_IA32_SYSENTER_CS, (u64)__KERNEL_CS);
wrmsrl_safe(MSR_IA32_SYSENTER_ESP, 0ULL);
- wrmsrl_safe(MSR_IA32_SYSENTER_EIP, (u64)ia32_sysenter_target);
+ wrmsrl_safe(MSR_IA32_SYSENTER_EIP, (u64)entry_SYSENTER_compat);
#else
wrmsrl(MSR_CSTAR, ignore_sysret);
wrmsrl_safe(MSR_IA32_SYSENTER_CS, (u64)GDT_ENTRY_INVALID_SEG);
diff --git a/arch/x86/xen/xen-asm_64.S b/arch/x86/xen/xen-asm_64.S
index 3c43c03..ccac1b1 100644
--- a/arch/x86/xen/xen-asm_64.S
+++ b/arch/x86/xen/xen-asm_64.S
@@ -128,7 +128,7 @@
/* 32-bit compat sysenter target */
ENTRY(xen_sysenter_target)
undo_xen_syscall
- jmp ia32_sysenter_target
+ jmp entry_SYSENTER_compat
ENDPROC(xen_sysenter_target)
#else /* !CONFIG_IA32_EMULATION */
