From patchwork Mon Jun 4 15:51:53 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Masami Hiramatsu (Google)" X-Patchwork-Id: 925137 Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from lists.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) (using TLSv1.2 with cipher ADH-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 41002T1qdfz9s08 for ; Tue, 5 Jun 2018 01:57:53 +1000 (AEST) Authentication-Results: ozlabs.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: ozlabs.org; dkim=fail reason="signature verification failed" (1024-bit key; unprotected) header.d=kernel.org header.i=@kernel.org header.b="lEVBFg/F"; dkim-atps=neutral Received: from lists.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 41002T07s6zF0dl for ; Tue, 5 Jun 2018 01:57:53 +1000 (AEST) Authentication-Results: lists.ozlabs.org; dmarc=pass (p=none dis=none) header.from=kernel.org Authentication-Results: lists.ozlabs.org; dkim=fail reason="signature verification failed" (1024-bit key; unprotected) header.d=kernel.org header.i=@kernel.org header.b="lEVBFg/F"; dkim-atps=neutral X-Original-To: linuxppc-dev@lists.ozlabs.org Delivered-To: linuxppc-dev@lists.ozlabs.org Authentication-Results: lists.ozlabs.org; spf=pass (mailfrom) smtp.mailfrom=kernel.org (client-ip=198.145.29.99; helo=mail.kernel.org; envelope-from=mhiramat@kernel.org; receiver=) Authentication-Results: lists.ozlabs.org; dmarc=pass (p=none dis=none) header.from=kernel.org Authentication-Results: lists.ozlabs.org; dkim=pass (1024-bit key; unprotected) header.d=kernel.org header.i=@kernel.org header.b="lEVBFg/F"; dkim-atps=neutral Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 40zzw33l2zzDrYf for ; Tue, 5 Jun 2018 01:52:19 +1000 (AEST) Received: from localhost.localdomain (NE2965lan1.rev.em-net.ne.jp [210.141.244.193]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id BCFA720895; Mon, 4 Jun 2018 15:52:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1528127537; bh=DdZtKtBJGwyBOt9Ils1XaANOM5BMFyA/RlpA7Han/rU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=lEVBFg/FBqKQTbGMy0Wmk76xj0ViYWZfvCP5nlvIVBWllvkwWLTXZA53lvPA18Tuw 4lXc4eFbQnckazZqFddGvE+6WOoJxnTxNbQErW6pF/gC1l7NIXWVTKO/l3NamKNjjo G+O2h2ceWdqm0F/B8BZBW7DLZvA+hNpqettJIUt0= From: Masami Hiramatsu To: Thomas Gleixner , Ingo Molnar Subject: [RFC PATCH -tip v5 07/27] powerpc/kprobes: Remove jprobe powerpc implementation Date: Tue, 5 Jun 2018 00:51:53 +0900 Message-Id: <152812751377.10068.6090934299713110701.stgit@devbox> X-Mailer: git-send-email 2.13.6 In-Reply-To: <152812730943.10068.5166429445118734697.stgit@devbox> References: <152812730943.10068.5166429445118734697.stgit@devbox> User-Agent: StGit/0.17.1-dirty MIME-Version: 1.0 X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.26 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org, Ingo Molnar , Steven Rostedt , Masami Hiramatsu , "H . Peter Anvin" , Paul Mackerras , Andrew Morton , linuxppc-dev@lists.ozlabs.org, "Naveen N. Rao" Errors-To: linuxppc-dev-bounces+patchwork-incoming=ozlabs.org@lists.ozlabs.org Sender: "Linuxppc-dev" Remove arch dependent setjump/longjump functions and unused fields in kprobe_ctlblk for jprobes from arch/powerpc. This also reverts commits related __is_active_jprobe() function. Signed-off-by: Masami Hiramatsu Cc: Benjamin Herrenschmidt Cc: Paul Mackerras Cc: Michael Ellerman Cc: "Naveen N. Rao" Cc: linuxppc-dev@lists.ozlabs.org Acked-by: Naveen N. Rao --- arch/powerpc/include/asm/kprobes.h | 2 - arch/powerpc/kernel/kprobes-ftrace.c | 15 ------- arch/powerpc/kernel/kprobes.c | 54 ------------------------ arch/powerpc/kernel/trace/ftrace_64_mprofile.S | 39 ++--------------- 4 files changed, 5 insertions(+), 105 deletions(-) diff --git a/arch/powerpc/include/asm/kprobes.h b/arch/powerpc/include/asm/kprobes.h index 9f3be5c8a4a3..674036db558b 100644 --- a/arch/powerpc/include/asm/kprobes.h +++ b/arch/powerpc/include/asm/kprobes.h @@ -88,7 +88,6 @@ struct prev_kprobe { struct kprobe_ctlblk { unsigned long kprobe_status; unsigned long kprobe_saved_msr; - struct pt_regs jprobe_saved_regs; struct prev_kprobe prev_kprobe; }; @@ -104,7 +103,6 @@ extern int kprobe_fault_handler(struct pt_regs *regs, int trapnr); extern int kprobe_handler(struct pt_regs *regs); extern int kprobe_post_handler(struct pt_regs *regs); #ifdef CONFIG_KPROBES_ON_FTRACE -extern int __is_active_jprobe(unsigned long addr); extern int skip_singlestep(struct kprobe *p, struct pt_regs *regs, struct kprobe_ctlblk *kcb); #else diff --git a/arch/powerpc/kernel/kprobes-ftrace.c b/arch/powerpc/kernel/kprobes-ftrace.c index 7a1f99f1b47f..1b316331c2d9 100644 --- a/arch/powerpc/kernel/kprobes-ftrace.c +++ b/arch/powerpc/kernel/kprobes-ftrace.c @@ -25,21 +25,6 @@ #include #include -/* - * This is called from ftrace code after invoking registered handlers to - * disambiguate regs->nip changes done by jprobes and livepatch. We check if - * there is an active jprobe at the provided address (mcount location). - */ -int __is_active_jprobe(unsigned long addr) -{ - if (!preemptible()) { - struct kprobe *p = raw_cpu_read(current_kprobe); - return (p && (unsigned long)p->addr == addr) ? 1 : 0; - } - - return 0; -} - static nokprobe_inline int __skip_singlestep(struct kprobe *p, struct pt_regs *regs, struct kprobe_ctlblk *kcb, unsigned long orig_nip) diff --git a/arch/powerpc/kernel/kprobes.c b/arch/powerpc/kernel/kprobes.c index e4c5bf33970b..600678fce0a8 100644 --- a/arch/powerpc/kernel/kprobes.c +++ b/arch/powerpc/kernel/kprobes.c @@ -611,60 +611,6 @@ unsigned long arch_deref_entry_point(void *entry) } NOKPROBE_SYMBOL(arch_deref_entry_point); -int setjmp_pre_handler(struct kprobe *p, struct pt_regs *regs) -{ - struct jprobe *jp = container_of(p, struct jprobe, kp); - struct kprobe_ctlblk *kcb = get_kprobe_ctlblk(); - - memcpy(&kcb->jprobe_saved_regs, regs, sizeof(struct pt_regs)); - - /* setup return addr to the jprobe handler routine */ - regs->nip = arch_deref_entry_point(jp->entry); -#ifdef PPC64_ELF_ABI_v2 - regs->gpr[12] = (unsigned long)jp->entry; -#elif defined(PPC64_ELF_ABI_v1) - regs->gpr[2] = (unsigned long)(((func_descr_t *)jp->entry)->toc); -#endif - - /* - * jprobes use jprobe_return() which skips the normal return - * path of the function, and this messes up the accounting of the - * function graph tracer. - * - * Pause function graph tracing while performing the jprobe function. - */ - pause_graph_tracing(); - - return 1; -} -NOKPROBE_SYMBOL(setjmp_pre_handler); - -void __used jprobe_return(void) -{ - asm volatile("jprobe_return_trap:\n" - "trap\n" - ::: "memory"); -} -NOKPROBE_SYMBOL(jprobe_return); - -int longjmp_break_handler(struct kprobe *p, struct pt_regs *regs) -{ - struct kprobe_ctlblk *kcb = get_kprobe_ctlblk(); - - if (regs->nip != ppc_kallsyms_lookup_name("jprobe_return_trap")) { - pr_debug("longjmp_break_handler NIP (0x%lx) does not match jprobe_return_trap (0x%lx)\n", - regs->nip, ppc_kallsyms_lookup_name("jprobe_return_trap")); - return 0; - } - - memcpy(regs, &kcb->jprobe_saved_regs, sizeof(struct pt_regs)); - /* It's OK to start function graph tracing again */ - unpause_graph_tracing(); - preempt_enable_no_resched(); - return 1; -} -NOKPROBE_SYMBOL(longjmp_break_handler); - static struct kprobe trampoline_p = { .addr = (kprobe_opcode_t *) &kretprobe_trampoline, .pre_handler = trampoline_probe_handler diff --git a/arch/powerpc/kernel/trace/ftrace_64_mprofile.S b/arch/powerpc/kernel/trace/ftrace_64_mprofile.S index 3f3e81852422..4e84a713e80a 100644 --- a/arch/powerpc/kernel/trace/ftrace_64_mprofile.S +++ b/arch/powerpc/kernel/trace/ftrace_64_mprofile.S @@ -99,39 +99,13 @@ ftrace_call: bl ftrace_stub nop - /* Load the possibly modified NIP */ - ld r15, _NIP(r1) - + /* Load ctr with the possibly modified NIP */ + ld r3, _NIP(r1) + mtctr r3 #ifdef CONFIG_LIVEPATCH - cmpd r14, r15 /* has NIP been altered? */ + cmpd r14, r3 /* has NIP been altered? */ #endif -#if defined(CONFIG_LIVEPATCH) && defined(CONFIG_KPROBES_ON_FTRACE) - /* NIP has not been altered, skip over further checks */ - beq 1f - - /* Check if there is an active jprobe on us */ - subi r3, r14, 4 - bl __is_active_jprobe - nop - - /* - * If r3 == 1, then this is a kprobe/jprobe. - * else, this is livepatched function. - * - * The conditional branch for livepatch_handler below will use the - * result of this comparison. For kprobe/jprobe, we just need to branch to - * the new NIP, not call livepatch_handler. The branch below is bne, so we - * want CR0[EQ] to be true if this is a kprobe/jprobe. Which means we want - * CR0[EQ] = (r3 == 1). - */ - cmpdi r3, 1 -1: -#endif - - /* Load CTR with the possibly modified NIP */ - mtctr r15 - /* Restore gprs */ REST_GPR(0,r1) REST_10GPRS(2,r1) @@ -149,10 +123,7 @@ ftrace_call: addi r1, r1, SWITCH_FRAME_SIZE #ifdef CONFIG_LIVEPATCH - /* - * Based on the cmpd or cmpdi above, if the NIP was altered and we're - * not on a kprobe/jprobe, then handle livepatch. - */ + /* Based on the cmpd above, if the NIP was altered handle livepatch */ bne- livepatch_handler #endif