From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-3.7 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id BE11BC47254 for ; Tue, 5 May 2020 14:19:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9E12720675 for ; Tue, 5 May 2020 14:19:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730471AbgEEOTO (ORCPT ); Tue, 5 May 2020 10:19:14 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49126 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1730088AbgEEOQW (ORCPT ); Tue, 5 May 2020 10:16:22 -0400 Received: from Galois.linutronix.de (Galois.linutronix.de [IPv6:2a0a:51c0:0:12e:550::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D5631C061A0F for ; Tue, 5 May 2020 07:16:21 -0700 (PDT) Received: from p5de0bf0b.dip0.t-ipconnect.de ([93.224.191.11] helo=nanos.tec.linutronix.de) by Galois.linutronix.de with esmtpsa (TLS1.2:DHE_RSA_AES_256_CBC_SHA256:256) (Exim 4.80) (envelope-from ) id 1jVyMe-00024a-Gw; Tue, 05 May 2020 16:16:04 +0200 Received: from nanos.tec.linutronix.de (localhost [IPv6:::1]) by nanos.tec.linutronix.de (Postfix) with ESMTP id 18C0BFFC8D; Tue, 5 May 2020 16:16:04 +0200 (CEST) Message-Id: <20200505135314.900297476@linutronix.de> User-Agent: quilt/0.65 Date: Tue, 05 May 2020 15:49:42 +0200 From: Thomas Gleixner To: LKML Cc: x86@kernel.org, "Paul E. McKenney" , Andy Lutomirski , Alexandre Chartre , Frederic Weisbecker , Paolo Bonzini , Sean Christopherson , Masami Hiramatsu , Petr Mladek , Steven Rostedt , Joel Fernandes , Boris Ostrovsky , Juergen Gross , Brian Gerst , Mathieu Desnoyers , Josh Poimboeuf , Will Deacon Subject: [patch V4 part 4 16/24] x86/entry: Convert Debug exception to IDTENTRY_DB References: <20200505134926.578885807@linutronix.de> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-transfer-encoding: 8-bit X-Linutronix-Spam-Score: -1.0 X-Linutronix-Spam-Level: - X-Linutronix-Spam-Status: No , -1.0 points, 5.0 required, ALL_TRUSTED=-1,SHORTCIRCUIT=-0.0001 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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 prototyoes No functional change. Signed-off-by: Thomas Gleixner --- arch/x86/entry/entry_32.S | 10 ---------- arch/x86/entry/entry_64.S | 2 -- arch/x86/include/asm/idtentry.h | 4 ++++ arch/x86/include/asm/traps.h | 3 --- arch/x86/kernel/idt.c | 8 ++++---- arch/x86/kernel/traps.c | 21 +++++++++++++-------- arch/x86/xen/enlighten_pv.c | 2 +- arch/x86/xen/xen-asm_64.S | 4 ++-- 8 files changed, 24 insertions(+), 30 deletions(-) --- a/arch/x86/entry/entry_32.S +++ b/arch/x86/entry/entry_32.S @@ -1488,16 +1488,6 @@ SYM_CODE_START_LOCAL_NOALIGN(handle_exce 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) - #ifdef CONFIG_DOUBLEFAULT SYM_CODE_START(double_fault) 1: --- a/arch/x86/entry/entry_64.S +++ b/arch/x86/entry/entry_64.S @@ -1075,12 +1075,10 @@ apicinterrupt IRQ_WORK_VECTOR irq_work 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 /* --- a/arch/x86/include/asm/idtentry.h +++ b/arch/x86/include/asm/idtentry.h @@ -262,4 +262,8 @@ DECLARE_IDTENTRY_MCE(X86_TRAP_MC, exc_ma 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 --- a/arch/x86/include/asm/traps.h +++ b/arch/x86/include/asm/traps.h @@ -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); #if defined(CONFIG_X86_64) || defined(CONFIG_DOUBLEFAULT) dotraplinkage void do_double_fault(struct pt_regs *regs, long error_code, unsigned long cr2); #endif --- a/arch/x86/kernel/idt.c +++ b/arch/x86/kernel/idt.c @@ -56,7 +56,7 @@ struct idt_data { * 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), @@ -90,7 +90,7 @@ static const __initconst struct idt_data #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), @@ -161,7 +161,7 @@ static const __initconst struct idt_data * 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 @@ -182,7 +182,7 @@ gate_desc debug_idt_table[IDT_ENTRIES] _ * 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 --- a/arch/x86/kernel/traps.c +++ b/arch/x86/kernel/traps.c @@ -753,7 +753,7 @@ static __always_inline void debug_exit(u * * May run on IST stack. */ -dotraplinkage void do_debug(struct pt_regs *regs, long error_code) +DEFINE_IDTENTRY_DEBUG(exc_debug) { struct task_struct *tsk = current; unsigned long dr6, dr7; @@ -762,7 +762,10 @@ dotraplinkage void do_debug(struct pt_re debug_enter(&dr6, &dr7); - nmi_enter(); + if (user_mode(regs)) + idtentry_enter(regs); + else + nmi_enter(); /* * The SDM says "The processor clears the BTF flag when it @@ -799,7 +802,7 @@ dotraplinkage void do_debug(struct pt_re goto exit; #endif - if (notify_die(DIE_DEBUG, "debug", regs, (long)&dr6, error_code, + if (notify_die(DIE_DEBUG, "debug", regs, (long)&dr6, 0, SIGTRAP) == NOTIFY_STOP) goto exit; @@ -813,8 +816,8 @@ dotraplinkage void do_debug(struct pt_re cond_local_irq_enable(regs); if (v8086_mode(regs)) { - handle_vm86_trap((struct kernel_vm86_regs *) regs, error_code, - X86_TRAP_DB); + handle_vm86_trap((struct kernel_vm86_regs *) regs, 0, + X86_TRAP_DB); cond_local_irq_disable(regs); debug_stack_usage_dec(); goto exit; @@ -833,15 +836,17 @@ dotraplinkage void do_debug(struct pt_re } si_code = get_si_code(tsk->thread.debugreg6); if (tsk->thread.debugreg6 & (DR_STEP | DR_TRAP_BITS) || user_icebp) - send_sigtrap(regs, error_code, si_code); + send_sigtrap(regs, 0, si_code); cond_local_irq_disable(regs); debug_stack_usage_dec(); exit: - nmi_exit(); + if (user_mode(regs)) + idtentry_exit(regs); + else + nmi_exit(); debug_exit(dr7); } -NOKPROBE_SYMBOL(do_debug); /* * Note that we play around with the 'TS' bit in an attempt to get --- a/arch/x86/xen/enlighten_pv.c +++ b/arch/x86/xen/enlighten_pv.c @@ -616,7 +616,7 @@ struct trap_array_entry { .ist_okay = ist_ok } static struct trap_array_entry trap_array[] = { - { debug, xen_xendebug, true }, + TRAP_ENTRY_REDIR(exc_debug, exc_xendebug, true ), { double_fault, xen_double_fault, true }, #ifdef CONFIG_X86_MCE TRAP_ENTRY(exc_machine_check, true ), --- a/arch/x86/xen/xen-asm_64.S +++ b/arch/x86/xen/xen-asm_64.S @@ -29,8 +29,8 @@ SYM_CODE_END(xen_\name) .endm xen_pv_trap asm_exc_divide_error -xen_pv_trap debug -xen_pv_trap xendebug +xen_pv_trap asm_exc_debug +xen_pv_trap asm_exc_xendebug xen_pv_trap asm_exc_int3 xen_pv_trap asm_exc_xennmi xen_pv_trap asm_exc_overflow