From nobody Mon Apr 13 16:57:43 2026 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 57713C433FE for ; Mon, 14 Nov 2022 16:30:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237625AbiKNQaY (ORCPT ); Mon, 14 Nov 2022 11:30:24 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35626 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237537AbiKNQ3l (ORCPT ); Mon, 14 Nov 2022 11:29:41 -0500 Received: from galois.linutronix.de (Galois.linutronix.de [IPv6:2a0a:51c0:0:12e:550::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2BA13102C for ; Mon, 14 Nov 2022 08:29:41 -0800 (PST) From: John Ogness DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1668443379; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=GEhKO0dJc2f16pdA5isP3tyKiWxAMb8gJwHLg9bJtvU=; b=fED6VtmDED6MuLvYHCpr7jg0s8uQ4ubFuV+VJrDBURlb+sRmrPLVdZhbCg7C9vkvldCcZC O3jnP3sS40Xc/9Nl61qOPe4tQo5M701OfeqSfviyYjbM9aVF5lpkSd4rH9cAes5ZiqmRXV qSC0fmcpzoHohSsnvCqpR2jm74hLpeXfas4Urmb+nz47yUrVVMWUckuYe0K6QhSQ0thxYe Do4tLzYO/CeZJ4lQo1ewHWpTh8mj47O/uroIOAzyntCZsQtDNfsDD/JIDWJTssmb6VX7O6 7zwiYUW4aXXfoFUuEEQfPo3tGoBVRNEWeL66ULaqMgc89bm5V3SqUuiZVWBb3A== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1668443379; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=GEhKO0dJc2f16pdA5isP3tyKiWxAMb8gJwHLg9bJtvU=; b=X+VenatF4kHSWTowXfqC0zSVEJludzZYKhc6X1KeZyez9dy82GgAGpy+a7Avhfw9vUOvoe nAz42aPySqUAAZDA== To: Petr Mladek Cc: Sergey Senozhatsky , Steven Rostedt , Thomas Gleixner , linux-kernel@vger.kernel.org, Richard Weinberger , Anton Ivanov , Johannes Berg , linux-um@lists.infradead.org Subject: [PATCH printk v4 12/39] um: kmsg_dumper: use srcu console list iterator Date: Mon, 14 Nov 2022 17:35:05 +0106 Message-Id: <20221114162932.141883-13-john.ogness@linutronix.de> In-Reply-To: <20221114162932.141883-1-john.ogness@linutronix.de> References: <20221114162932.141883-1-john.ogness@linutronix.de> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" Rather than using the console_lock to guarantee safe console list traversal, use srcu console list iteration. Signed-off-by: John Ogness Reviewed-by: Petr Mladek --- arch/um/kernel/kmsg_dump.c | 13 +++++-------- 1 file changed, 5 insertions(+), 8 deletions(-) diff --git a/arch/um/kernel/kmsg_dump.c b/arch/um/kernel/kmsg_dump.c index 40abf1e9ccb1..427dd5a61a38 100644 --- a/arch/um/kernel/kmsg_dump.c +++ b/arch/um/kernel/kmsg_dump.c @@ -16,29 +16,26 @@ static void kmsg_dumper_stdout(struct kmsg_dumper *dump= er, struct console *con; unsigned long flags; size_t len =3D 0; + int cookie; =20 /* * If no consoles are available to output crash information, dump * the kmsg buffer to stdout. */ =20 - if (!console_trylock()) - return; - - for_each_console(con) { + cookie =3D console_srcu_read_lock(); + for_each_console_srcu(con) { /* * The ttynull console and disabled consoles are ignored * since they cannot output. All other consoles are * expected to output the crash information. */ if (strcmp(con->name, "ttynull") !=3D 0 && - (con->flags & CON_ENABLED)) { + (console_srcu_read_flags(con) & CON_ENABLED)) { break; } } - - console_unlock(); - + console_srcu_read_unlock(cookie); if (con) return; =20 --=20 2.30.2