[patch 11/24] x86/entry: Convert Bounds exception to IDTENTRY

Thomas Gleixner
2020-02-25T23:29:25Z

Convert #BR to IDTENTRY:
- Implement the C entry point with DEFINE_IDTENTRY
- Emit the ASM stub with DECLARE_IDTENTRY
- Remove the ASM idtentry in 64bit
- Remove the open coded ASM entry code in 32bit
- Fixup the XEN/PV code
- Remove the old prototyoes

No functional change.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---
arch/x86/entry/entry_32.S | 7 -------
arch/x86/entry/entry_64.S | 1 -
arch/x86/include/asm/idtentry.h | 1 +
arch/x86/include/asm/traps.h | 3 ---
arch/x86/kernel/idt.c | 2 +-
arch/x86/kernel/traps.c | 10 +++++-----
arch/x86/xen/enlighten_pv.c | 2 +-
arch/x86/xen/xen-asm_64.S | 2 +-
8 files changed, 9 insertions(+), 19 deletions(-)

--- a/arch/x86/entry/entry_32.S
+++ b/arch/x86/entry/entry_32.S
@@ -1334,13 +1334,6 @@ SYM_CODE_START(native_iret)
SYM_CODE_END(native_iret)
#endif

-SYM_CODE_START(bounds)
- ASM_CLAC
- pushl $0
- pushl $do_bounds
- jmp common_exception
-SYM_CODE_END(bounds)
-
SYM_CODE_START(invalid_op)
ASM_CLAC
pushl $0
--- a/arch/x86/entry/entry_64.S
+++ b/arch/x86/entry/entry_64.S
@@ -1061,7 +1061,6 @@ apicinterrupt IRQ_WORK_VECTOR irq_work
* Exception entry points.
*/

-idtentry X86_TRAP_BR bounds do_bounds has_error_code=0
idtentry X86_TRAP_UD invalid_op do_invalid_op has_error_code=0
idtentry X86_TRAP_NM device_not_available do_device_not_available has_error_code=0
idtentry X86_TRAP_OLD_MF coprocessor_segment_overrun do_coprocessor_segment_overrun has_error_code=0
--- a/arch/x86/include/asm/idtentry.h
+++ b/arch/x86/include/asm/idtentry.h
@@ -80,5 +80,6 @@ static __always_inline void __##func(str
DECLARE_IDTENTRY(X86_TRAP_DE, exc_divide_error);
DECLARE_IDTENTRY(X86_TRAP_BP, exc_int3);
DECLARE_IDTENTRY(X86_TRAP_OF, exc_overflow);
+DECLARE_IDTENTRY(X86_TRAP_BR, exc_bounds);

#endif
--- a/arch/x86/include/asm/traps.h
+++ b/arch/x86/include/asm/traps.h
@@ -13,7 +13,6 @@

asmlinkage void debug(void);
asmlinkage void nmi(void);
-asmlinkage void bounds(void);
asmlinkage void invalid_op(void);
asmlinkage void device_not_available(void);
#ifdef CONFIG_X86_64
@@ -37,7 +36,6 @@ asmlinkage void simd_coprocessor_error(v
#if defined(CONFIG_X86_64) && defined(CONFIG_XEN_PV)
asmlinkage void xen_xennmi(void);
asmlinkage void xen_xendebug(void);
-asmlinkage void xen_bounds(void);
asmlinkage void xen_invalid_op(void);
asmlinkage void xen_device_not_available(void);
asmlinkage void xen_double_fault(void);
@@ -58,7 +56,6 @@ asmlinkage void xen_simd_coprocessor_err

dotraplinkage void do_debug(struct pt_regs *regs, long error_code);
dotraplinkage void do_nmi(struct pt_regs *regs, long error_code);
-dotraplinkage void do_bounds(struct pt_regs *regs, long error_code);
dotraplinkage void do_invalid_op(struct pt_regs *regs, long error_code);
dotraplinkage void do_device_not_available(struct pt_regs *regs, long error_code);
#if defined(CONFIG_X86_64) || defined(CONFIG_DOUBLEFAULT)
--- a/arch/x86/kernel/idt.c
+++ b/arch/x86/kernel/idt.c
@@ -72,7 +72,7 @@ static const __initconst struct idt_data
static const __initconst struct idt_data def_idts[] = {
INTG(X86_TRAP_DE, asm_exc_divide_error),
INTG(X86_TRAP_NMI, nmi),
- INTG(X86_TRAP_BR, bounds),
+ INTG(X86_TRAP_BR, asm_exc_bounds),
INTG(X86_TRAP_UD, invalid_op),
INTG(X86_TRAP_NM, device_not_available),
INTG(X86_TRAP_OLD_MF, coprocessor_segment_overrun),
--- a/arch/x86/kernel/traps.c
+++ b/arch/x86/kernel/traps.c
@@ -446,18 +446,18 @@ dotraplinkage void do_double_fault(struc
}
#endif

-dotraplinkage void do_bounds(struct pt_regs *regs, long error_code)
+DEFINE_IDTENTRY(exc_bounds)
{
RCU_LOCKDEP_WARN(!rcu_is_watching(), "entry code didn't wake RCU");
- if (notify_die(DIE_TRAP, "bounds", regs, error_code,
- X86_TRAP_BR, SIGSEGV) == NOTIFY_STOP)
+ if (notify_die(DIE_TRAP, "bounds", regs, 0,
+ X86_TRAP_BR, SIGSEGV) == NOTIFY_STOP)
return;
cond_local_irq_enable(regs);

if (!user_mode(regs))
- die("bounds", regs, error_code);
+ die("bounds", regs, 0);

- do_trap(X86_TRAP_BR, SIGSEGV, "bounds", regs, error_code, 0, NULL);
+ do_trap(X86_TRAP_BR, SIGSEGV, "bounds", regs, 0, 0, NULL);
}

enum kernel_gp_hint {
--- a/arch/x86/xen/enlighten_pv.c
+++ b/arch/x86/xen/enlighten_pv.c
@@ -621,7 +621,7 @@ static struct trap_array_entry trap_arra
#endif
{ page_fault, xen_page_fault, false },
TRAP_ENTRY(exc_divide_error, false ),
- { bounds, xen_bounds, false },
+ TRAP_ENTRY(exc_bounds, false ),
{ invalid_op, xen_invalid_op, false },
{ device_not_available, xen_device_not_available, false },
{ coprocessor_segment_overrun, xen_coprocessor_segment_overrun, false },
--- a/arch/x86/xen/xen-asm_64.S
+++ b/arch/x86/xen/xen-asm_64.S
@@ -34,7 +34,7 @@ xen_pv_trap xendebug
xen_pv_trap asm_exc_int3
xen_pv_trap xennmi
xen_pv_trap asm_exc_overflow
-xen_pv_trap bounds
+xen_pv_trap asm_exc_bounds
xen_pv_trap invalid_op
xen_pv_trap device_not_available
xen_pv_trap double_fault