[patch 22/24] x86/entry: Convert Alignment check exception to IDTENTRY

Thomas Gleixner
2020-02-25T23:29:07Z

Convert #AC to IDTENTRY_ERRORCODE:
- 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 | 6 ------
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 | 12 ++++--------
arch/x86/xen/enlighten_pv.c | 2 +-
arch/x86/xen/xen-asm_64.S | 2 +-
8 files changed, 8 insertions(+), 21 deletions(-)

--- a/arch/x86/entry/entry_32.S
+++ b/arch/x86/entry/entry_32.S
@@ -1320,12 +1320,6 @@ SYM_CODE_START(native_iret)
SYM_CODE_END(native_iret)
#endif

-SYM_CODE_START(alignment_check)
- ASM_CLAC
- pushl $do_alignment_check
- jmp common_exception
-SYM_CODE_END(alignment_check)
-
#ifdef CONFIG_X86_MCE
SYM_CODE_START(machine_check)
ASM_CLAC
--- 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_AC alignment_check do_alignment_check has_error_code=1
idtentry X86_TRAP_XF simd_coprocessor_error do_simd_coprocessor_error has_error_code=0

idtentry X86_TRAP_PF page_fault do_page_fault has_error_code=1
--- a/arch/x86/include/asm/idtentry.h
+++ b/arch/x86/include/asm/idtentry.h
@@ -135,5 +135,6 @@ DECLARE_IDTENTRY_ERRORCODE(X86_TRAP_TS,
DECLARE_IDTENTRY_ERRORCODE(X86_TRAP_NP, exc_segment_not_present);
DECLARE_IDTENTRY_ERRORCODE(X86_TRAP_SS, exc_stack_segment);
DECLARE_IDTENTRY_ERRORCODE(X86_TRAP_GP, exc_general_protection);
+DECLARE_IDTENTRY_ERRORCODE(X86_TRAP_AC, exc_alignment_check);

#endif
--- a/arch/x86/include/asm/traps.h
+++ b/arch/x86/include/asm/traps.h
@@ -18,7 +18,6 @@ asmlinkage void double_fault(void);
#endif
asmlinkage void page_fault(void);
asmlinkage void async_page_fault(void);
-asmlinkage void alignment_check(void);
#ifdef CONFIG_X86_MCE
asmlinkage void machine_check(void);
#endif /* CONFIG_X86_MCE */
@@ -29,7 +28,6 @@ asmlinkage void xen_xennmi(void);
asmlinkage void xen_xendebug(void);
asmlinkage void xen_double_fault(void);
asmlinkage void xen_page_fault(void);
-asmlinkage void xen_alignment_check(void);
#ifdef CONFIG_X86_MCE
asmlinkage void xen_machine_check(void);
#endif /* CONFIG_X86_MCE */
@@ -42,7 +40,6 @@ dotraplinkage void do_nmi(struct pt_regs
dotraplinkage void do_double_fault(struct pt_regs *regs, long error_code, unsigned long cr2);
#endif
dotraplinkage void do_page_fault(struct pt_regs *regs, unsigned long error_code, unsigned long address);
-dotraplinkage void do_alignment_check(struct pt_regs *regs, long error_code);
dotraplinkage void do_simd_coprocessor_error(struct pt_regs *regs, long error_code);
#ifdef CONFIG_X86_32
dotraplinkage void do_iret_error(struct pt_regs *regs, long error_code);
--- a/arch/x86/kernel/idt.c
+++ b/arch/x86/kernel/idt.c
@@ -82,7 +82,7 @@ static const __initconst struct idt_data
INTG(X86_TRAP_GP, asm_exc_general_protection),
INTG(X86_TRAP_SPURIOUS, asm_exc_spurious_interrupt_bug),
INTG(X86_TRAP_MF, asm_exc_coprocessor_error),
- INTG(X86_TRAP_AC, alignment_check),
+ INTG(X86_TRAP_AC, asm_exc_alignment_check),
INTG(X86_TRAP_XF, simd_coprocessor_error),

#ifdef CONFIG_X86_32
--- a/arch/x86/kernel/traps.c
+++ b/arch/x86/kernel/traps.c
@@ -320,16 +320,12 @@ DEFINE_IDTENTRY_ERRORCODE(exc_stack_segm
0, NULL);
}

-#define IP ((void __user *)uprobe_get_trap_addr(regs))
-#define DO_ERROR(trapnr, signr, sicode, addr, str, name) \
-dotraplinkage void do_##name(struct pt_regs *regs, long error_code) \
-{ \
- do_error_trap(regs, error_code, str, trapnr, signr, sicode, addr); \
+DEFINE_IDTENTRY_ERRORCODE(exc_alignment_check)
+{
+ do_error_trap(regs, error_code, "alignement check", X86_TRAP_AC,
+ SIGBUS, BUS_ADRALN, NULL);
}

-DO_ERROR(X86_TRAP_AC, SIGBUS, BUS_ADRALN, NULL, "alignment check", alignment_check)
-#undef IP
-
#ifdef CONFIG_VMAP_STACK
__visible void __noreturn handle_stack_overflow(const char *message,
struct pt_regs *regs,
--- a/arch/x86/xen/enlighten_pv.c
+++ b/arch/x86/xen/enlighten_pv.c
@@ -631,7 +631,7 @@ static struct trap_array_entry trap_arra
TRAP_ENTRY(exc_general_protection, false ),
TRAP_ENTRY(exc_spurious_interrupt_bug, false ),
TRAP_ENTRY(exc_coprocessor_error, false ),
- { alignment_check, xen_alignment_check, false },
+ TRAP_ENTRY(exc_alignment_check, false ),
{ simd_coprocessor_error, xen_simd_coprocessor_error, false },
};

--- a/arch/x86/xen/xen-asm_64.S
+++ b/arch/x86/xen/xen-asm_64.S
@@ -46,7 +46,7 @@ xen_pv_trap asm_exc_general_protection
xen_pv_trap page_fault
xen_pv_trap asm_exc_spurious_interrupt_bug
xen_pv_trap asm_exc_coprocessor_error
-xen_pv_trap alignment_check
+xen_pv_trap asm_exc_alignment_check
#ifdef CONFIG_X86_MCE
xen_pv_trap machine_check
#endif /* CONFIG_X86_MCE */