Commit 2bbc68f8 authored by Thomas Gleixner's avatar Thomas Gleixner
Browse files

x86/entry: Convert Debug exception to IDTENTRY_DB 



Convert #DB to IDTENTRY_ERRORCODE:
  - Implement the C entry point with DEFINE_IDTENTRY_DB
  - 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 prototypes

No functional change.

Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
Reviewed-by: default avatarAlexandre Chartre <alexandre.chartre@oracle.com>
Acked-by: default avatarPeter Zijlstra <peterz@infradead.org>
Acked-by: default avatarAndy Lutomirski <luto@kernel.org>
Link: https://lkml.kernel.org/r/20200505135314.900297476@linutronix.de
parent 9f58fdde

arch/x86/entry/entry_32.S

+0 −10
Original line number Diff line number Diff line
@@ -1488,16 +1488,6 @@ ret_to_user: 
	jmp	restore_all_switch_stack

SYM_CODE_END(handle_exception)



SYM_CODE_START(debug)

	/*

	 * Entry from sysenter is now handled in common_exception

	 */

	ASM_CLAC

	pushl	$0

	pushl	$do_debug

	jmp	common_exception

SYM_CODE_END(debug)



SYM_CODE_START(double_fault)

1:

	/*

arch/x86/entry/entry_64.S

+0 −2
Original line number Diff line number Diff line
@@ -1074,12 +1074,10 @@ apicinterrupt IRQ_WORK_VECTOR irq_work_interrupt smp_irq_work_interrupt 


idtentry	X86_TRAP_PF		page_fault		do_page_fault			has_error_code=1



idtentry_mce_db	X86_TRAP_DB		debug			do_debug

idtentry_df	X86_TRAP_DF		double_fault		do_double_fault



#ifdef CONFIG_XEN_PV

idtentry	512 /* dummy */		hypervisor_callback	xen_do_hypervisor_callback	has_error_code=0

idtentry	X86_TRAP_DB		xendebug		do_debug			has_error_code=0

#endif



/*

arch/x86/include/asm/idtentry.h

+4 −0
Original line number Diff line number Diff line
@@ -262,4 +262,8 @@ DECLARE_IDTENTRY_MCE(X86_TRAP_MC, exc_machine_check); 
DECLARE_IDTENTRY_NMI(X86_TRAP_NMI,	exc_nmi);

DECLARE_IDTENTRY_XEN(X86_TRAP_NMI,	nmi);



/* #DB */

DECLARE_IDTENTRY_DEBUG(X86_TRAP_DB,	exc_debug);

DECLARE_IDTENTRY_XEN(X86_TRAP_DB,	debug);



#endif

arch/x86/include/asm/traps.h

+0 −3
Original line number Diff line number Diff line
@@ -11,7 +11,6 @@ 


#define dotraplinkage __visible



asmlinkage void debug(void);

#ifdef CONFIG_X86_64

asmlinkage void double_fault(void);

#endif
@@ -19,12 +18,10 @@ asmlinkage void page_fault(void); 
asmlinkage void async_page_fault(void);



#if defined(CONFIG_X86_64) && defined(CONFIG_XEN_PV)

asmlinkage void xen_xendebug(void);

asmlinkage void xen_double_fault(void);

asmlinkage void xen_page_fault(void);

#endif



dotraplinkage void do_debug(struct pt_regs *regs, long error_code);

dotraplinkage void do_double_fault(struct pt_regs *regs, long error_code, unsigned long cr2);

dotraplinkage void do_page_fault(struct pt_regs *regs, unsigned long error_code, unsigned long address);

arch/x86/kernel/idt.c

+4 −4
Original line number Diff line number Diff line
@@ -59,7 +59,7 @@ static bool idt_setup_done __initdata; 
 * stacks work only after cpu_init().

 */

static const __initconst struct idt_data early_idts[] = {

	INTG(X86_TRAP_DB,		debug),

	INTG(X86_TRAP_DB,		asm_exc_debug),

	SYSG(X86_TRAP_BP,		asm_exc_int3),

#ifdef CONFIG_X86_32

	INTG(X86_TRAP_PF,		page_fault),
@@ -93,7 +93,7 @@ static const __initconst struct idt_data def_idts[] = { 
#else

	INTG(X86_TRAP_DF,		double_fault),

#endif

	INTG(X86_TRAP_DB,		debug),

	INTG(X86_TRAP_DB,		asm_exc_debug),



#ifdef CONFIG_X86_MCE

	INTG(X86_TRAP_MC,		asm_exc_machine_check),
@@ -164,7 +164,7 @@ static const __initconst struct idt_data early_pf_idts[] = { 
 * stack set to DEFAULT_STACK (0). Required for NMI trap handling.

 */

static const __initconst struct idt_data dbg_idts[] = {

	INTG(X86_TRAP_DB,	debug),

	INTG(X86_TRAP_DB,		asm_exc_debug),

};

#endif
@@ -185,7 +185,7 @@ gate_desc debug_idt_table[IDT_ENTRIES] __page_aligned_bss; 
 * cpu_init() when the TSS has been initialized.

 */

static const __initconst struct idt_data ist_idts[] = {

	ISTG(X86_TRAP_DB,	debug,			IST_INDEX_DB),

	ISTG(X86_TRAP_DB,	asm_exc_debug,		IST_INDEX_DB),

	ISTG(X86_TRAP_NMI,	asm_exc_nmi,		IST_INDEX_NMI),

	ISTG(X86_TRAP_DF,	double_fault,		IST_INDEX_DF),

#ifdef CONFIG_X86_MCE

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