Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754145AbbGFLD0 (ORCPT ); Mon, 6 Jul 2015 07:03:26 -0400 Received: from mail7.hitachi.co.jp ([133.145.228.42]:57438 "EHLO mail7.hitachi.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753554AbbGFLDZ (ORCPT ); Mon, 6 Jul 2015 07:03:25 -0400 Message-ID: <559A6075.5070502@hitachi.com> Date: Mon, 06 Jul 2015 20:03:17 +0900 From: Masami Hiramatsu Organization: Hitachi, Ltd., Japan User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:31.0) Gecko/20100101 Thunderbird/31.6.0 MIME-Version: 1.0 To: Pratyush Anand , linux-arm-kernel@lists.infradead.org, linux@arm.linux.org.uk, catalin.marinas@arm.com, will.deacon@arm.com CC: linux-kernel@vger.kernel.org, wcohen@redhat.com, dave.long@linaro.org, steve.capper@linaro.org Subject: Re: [PATCH 2/2] arm64: Make all entry code as non-kprobe-able References: <683f80cef9b2b778be868e77b01a245585448a86.1436158027.git.panand@redhat.com> In-Reply-To: <683f80cef9b2b778be868e77b01a245585448a86.1436158027.git.panand@redhat.com> Content-Type: text/plain; charset=iso-2022-jp Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2872 Lines: 91 On 2015/07/06 14:03, Pratyush Anand wrote: > Entry symbols are not kprobe safe. So blacklist them for kprobing. As I've said, you can also use _ASM_NOKPROBE(). This patch itself looks good to me, but I'd like to ask arm64 maintainers' opinion, whether they accept introducing entry-text section only for this purpose or not. Reviewed-by: Masami Hiramatsu Thank you, > > Signed-off-by: Pratyush Anand > --- > arch/arm64/kernel/entry.S | 3 +++ > arch/arm64/kernel/kprobes.c | 9 +++++++++ > arch/arm64/kernel/vmlinux.lds.S | 1 + > 3 files changed, 13 insertions(+) > > diff --git a/arch/arm64/kernel/entry.S b/arch/arm64/kernel/entry.S > index a7691a378668..2ea24f6bc06b 100644 > --- a/arch/arm64/kernel/entry.S > +++ b/arch/arm64/kernel/entry.S > @@ -202,6 +202,7 @@ tsk .req x28 // current thread_info > * Exception vectors. > */ > > + .section ".entry.text", "ax" > .align 11 > ENTRY(vectors) > ventry el1_sync_invalid // Synchronous EL1t > @@ -737,3 +738,5 @@ ENTRY(sys_rt_sigreturn_wrapper) > mov x0, sp > b sys_rt_sigreturn > ENDPROC(sys_rt_sigreturn_wrapper) > + > + .section ".text", "ax" > diff --git a/arch/arm64/kernel/kprobes.c b/arch/arm64/kernel/kprobes.c > index 6c9f8b5f04ce..9bc02c151f7f 100644 > --- a/arch/arm64/kernel/kprobes.c > +++ b/arch/arm64/kernel/kprobes.c > @@ -28,6 +28,7 @@ > #include > #include > #include > +#include > > #include "kprobes.h" > #include "kprobes-arm64.h" > @@ -661,6 +662,14 @@ int __kprobes arch_trampoline_kprobe(struct kprobe *p) > return 0; > } > > +bool arch_within_kprobe_blacklist(unsigned long addr) > +{ > + return (addr >= (unsigned long)__kprobes_text_start && > + addr < (unsigned long)__kprobes_text_end) || > + (addr >= (unsigned long)__entry_text_start && > + addr < (unsigned long)__entry_text_end); > +} > + > int __init arch_init_kprobes(void) > { > return 0; > diff --git a/arch/arm64/kernel/vmlinux.lds.S b/arch/arm64/kernel/vmlinux.lds.S > index 1fa6adc7aa83..11fb2b0117d0 100644 > --- a/arch/arm64/kernel/vmlinux.lds.S > +++ b/arch/arm64/kernel/vmlinux.lds.S > @@ -97,6 +97,7 @@ SECTIONS > *(.exception.text) > __exception_text_end = .; > IRQENTRY_TEXT > + ENTRY_TEXT > TEXT_TEXT > SCHED_TEXT > LOCK_TEXT > -- Masami HIRAMATSU Linux Technology Research Center, System Productivity Research Dept. Center for Technology Innovation - Systems Engineering Hitachi, Ltd., Research & Development Group E-mail: masami.hiramatsu.pt@hitachi.com -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/