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=-17.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham 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 5D00FC433E0 for ; Wed, 17 Mar 2021 14:25:20 +0000 (UTC) Received: from desiato.infradead.org (desiato.infradead.org [90.155.92.199]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id C9B8E64F26 for ; Wed, 17 Mar 2021 14:25:19 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org C9B8E64F26 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=huawei.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=desiato.20200630; h=Sender:Content-Transfer-Encoding :Content-Type:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To:Message-ID:Date: Subject:CC:To:From:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=M1eqDMGE8XZ13rEud+C6JfLQbZCHC4Le5cSPQ4A5ino=; b=bYYs6BV9RjiW0Wv0pUmg+hnoN dDCf+3VWkCXHYfnYirpisduvRH6FBGa/wkpZzb82U4VzYRKrp6AWGmDelPnkUyJf2/NwEmtNxpJOw K2cNQnoZqK7xq4y8Dt/S8w6FoLI+tGNUdOCzt7xdKxnjmN2fSHmsNLdz48W1msQjU7cHpQtGf4Qfk +aH2DQvoxw9Ig2D0zurfqfJLhdliabrvVzvIZ2EEcOp3qHpz7ttuCTCNeKUfQggiXFEzfYPUkFxh6 YMgwWOYD9OHSwTz+CLuCDum/uGNE/q55pn9dXh+6PxTFaZuL0Ulm5nASUXY3dnVUL8/L/z/EO+OE9 hfj9SUEJw==; Received: from localhost ([::1] helo=desiato.infradead.org) by desiato.infradead.org with esmtp (Exim 4.94 #2 (Red Hat Linux)) id 1lMX5D-003FcP-Qp; Wed, 17 Mar 2021 14:23:37 +0000 Received: from szxga04-in.huawei.com ([45.249.212.190]) by desiato.infradead.org with esmtps (Exim 4.94 #2 (Red Hat Linux)) id 1lMX4y-003FZP-2t for linux-arm-kernel@lists.infradead.org; Wed, 17 Mar 2021 14:23:22 +0000 Received: from DGGEMS409-HUB.china.huawei.com (unknown [172.30.72.59]) by szxga04-in.huawei.com (SkyGuard) with ESMTP id 4F0slh052dz17LBs; Wed, 17 Mar 2021 22:21:20 +0800 (CST) Received: from mdc.huawei.com (10.175.112.208) by DGGEMS409-HUB.china.huawei.com (10.3.19.209) with Microsoft SMTP Server id 14.3.498.0; Wed, 17 Mar 2021 22:23:03 +0800 From: Chen Jun To: , CC: , , , Subject: [PATCH 2/2] arm64: stacktrace: Add skip when task == current Date: Wed, 17 Mar 2021 14:20:50 +0000 Message-ID: <20210317142050.57712-3-chenjun102@huawei.com> X-Mailer: git-send-email 2.9.4 In-Reply-To: <20210317142050.57712-1-chenjun102@huawei.com> References: <20210317142050.57712-1-chenjun102@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.175.112.208] X-CFilter-Loop: Reflected X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210317_142320_699916_A0543C01 X-CRM114-Status: UNSURE ( 9.63 ) X-CRM114-Notice: Please train this message. X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On ARM64, cat /sys/kernel/debug/page_owner, all pages return the same stack: stack_trace_save+0x4c/0x78 register_early_stack+0x34/0x70 init_page_owner+0x34/0x230 page_ext_init+0x1bc/0x1dc The reason is that: check_recursive_alloc always return 1 because that entries[0] is always equal to ip (__set_page_owner+0x3c/0x60). The root cause is that: commit 5fc57df2f6fd ("arm64: stacktrace: Convert to ARCH_STACKWALK") make the save_trace save 2 more entries. Add skip in arch_stack_walk when task == current. Fixes: 5fc57df2f6fd ("arm64: stacktrace: Convert to ARCH_STACKWALK") Signed-off-by: Chen Jun --- arch/arm64/kernel/stacktrace.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/arch/arm64/kernel/stacktrace.c b/arch/arm64/kernel/stacktrace.c index ad20981..c26b0ac 100644 --- a/arch/arm64/kernel/stacktrace.c +++ b/arch/arm64/kernel/stacktrace.c @@ -201,11 +201,12 @@ void arch_stack_walk(stack_trace_consume_fn consume_entry, void *cookie, if (regs) start_backtrace(&frame, regs->regs[29], regs->pc); - else if (task == current) + else if (task == current) { + ((struct stacktrace_cookie *)cookie)->skip += 2; start_backtrace(&frame, (unsigned long)__builtin_frame_address(0), (unsigned long)arch_stack_walk); - else + } else start_backtrace(&frame, thread_saved_fp(task), thread_saved_pc(task)); -- 2.9.4 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel