From nobody Thu Apr 9 13:57:39 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 AC77CC433FE for ; Sat, 5 Nov 2022 21:49:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229925AbiKEVtE (ORCPT ); Sat, 5 Nov 2022 17:49:04 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39780 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230121AbiKEVss (ORCPT ); Sat, 5 Nov 2022 17:48:48 -0400 Received: from wout4-smtp.messagingengine.com (wout4-smtp.messagingengine.com [64.147.123.20]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 787E6DEBB for ; Sat, 5 Nov 2022 14:48:47 -0700 (PDT) Received: from compute2.internal (compute2.nyi.internal [10.202.2.46]) by mailout.west.internal (Postfix) with ESMTP id 8D843320034E; Sat, 5 Nov 2022 17:48:46 -0400 (EDT) Received: from mailfrontend2 ([10.202.2.163]) by compute2.internal (MEProxy); Sat, 05 Nov 2022 17:48:47 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sholland.org; h= cc:cc:content-transfer-encoding:date:date:from:from:in-reply-to :in-reply-to:message-id:mime-version:references:reply-to:sender :subject:subject:to:to; s=fm1; t=1667684926; x=1667771326; bh=Zc G1ArcUeKGaZd5PrcG3/1gsyCRPoz0HrnVVRDFda8o=; b=lt1OxjWmL1nd76byHp +iLUkjYf1FXz50/TIKpxCQ32IFhvnOi/5U6n/6LITuWcWty1X17uEPFrIkgP4J0X +zdzkEkXl3zqra9oQR3jcHgXUa5d/5xkHDhie31xFsRbN0Xduv2mRh4HHpULzyzN nvXloCvUet97MqU/X+toReAG5kVJe3vTpfGOmpe1VoRmKYGraaXOmKXwphZJ4sBj ZJKHdyJ7dTnJK30Hclt3Im9/ouLr5oiZl/kDS/ewBmzzDzmKTe1zCpoioG3tikBj X9UwDv6xQ/IpFOuiF3F5j2sAih1p0dZ4kmP3qOQkWBiXdBzsiqd5vijbajDVJBhI Mx0g== DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=cc:cc:content-transfer-encoding:date:date :feedback-id:feedback-id:from:from:in-reply-to:in-reply-to :message-id:mime-version:references:reply-to:sender:subject :subject:to:to:x-me-proxy:x-me-proxy:x-me-sender:x-me-sender :x-sasl-enc; s=fm3; t=1667684926; x=1667771326; bh=ZcG1ArcUeKGaZ d5PrcG3/1gsyCRPoz0HrnVVRDFda8o=; b=QxhX3TCnyL73D6/2ikOn311BWBU4F tyQcJAH7rIOr1ptw+OjFf5fdT8sZiNY42764LEbZIHxlLNfEr0fBw68M3a0k2y9P qlzX/A3NmkKqGnewHldOq0USkGFTCVwUbCrYEl6COC9/NKRnHDJ1wqNtzQIWKsrE tvhrjFfwb6cRRHyPlarOw2rL4TEdX7QfFW9MeM9I85BcXg3CLtt+IBY3YOIFap84 qhe+C2gY3aK+tOsIW11JwELtlk2fSnxe7Td25r1HS/Q/zI6HdZmqxNjYnHIXJNPK 8r4UwWO3ohG0tgHeYYY5KzzMynlsXo4x4a/TEEPEMYTQzJj2m2A3EzjSA== X-ME-Sender: X-ME-Received: X-ME-Proxy-Cause: gggruggvucftvghtrhhoucdtuddrgedvgedrvdeggdefkecutefuodetggdotefrodftvf curfhrohhfihhlvgemucfhrghsthforghilhdpqfgfvfdpuffrtefokffrpgfnqfghnecu uegrihhlohhuthemuceftddtnecusecvtfgvtghiphhivghnthhsucdlqddutddtmdenuc fjughrpefhvfevufffkffojghfggfgsedtkeertdertddtnecuhfhrohhmpefurghmuhgv lhcujfholhhlrghnugcuoehsrghmuhgvlhesshhhohhllhgrnhgurdhorhhgqeenucggtf frrghtthgvrhhnpedukeetueduhedtleetvefguddvvdejhfefudelgfduveeggeehgfdu feeitdevteenucevlhhushhtvghrufhiiigvpedtnecurfgrrhgrmhepmhgrihhlfhhroh hmpehsrghmuhgvlhesshhhohhllhgrnhgurdhorhhg X-ME-Proxy: Feedback-ID: i0ad843c9:Fastmail Received: by mail.messagingengine.com (Postfix) with ESMTPA; Sat, 5 Nov 2022 17:48:45 -0400 (EDT) From: Samuel Holland To: Dmitry Osipenko , "Rafael J . Wysocki" , Mark Rutland , Lorenzo Pieralisi Cc: linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Samuel Holland Subject: [PATCH 1/2] kernel/reboot: Use the static sys-off handler for any priority Date: Sat, 5 Nov 2022 16:48:39 -0500 Message-Id: <20221105214841.7828-2-samuel@sholland.org> X-Mailer: git-send-email 2.37.3 In-Reply-To: <20221105214841.7828-1-samuel@sholland.org> References: <20221105214841.7828-1-samuel@sholland.org> 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" commit 587b9bfe0668 ("kernel/reboot: Use static handler for register_platform_power_off()") addded a statically-allocated handler so register_sys_off_handler() could be called before the slab allocator is available. That behavior was limited to the SYS_OFF_PRIO_PLATFORM priority. However, it is also required for handlers such as PSCI on ARM, which needs to be registered at SYS_OFF_PRIO_FIRMWARE. Currently, this call stack crashes: start_kernel() setup_arch() psci_dt_init() psci_0_2_init() register_sys_off_handler() kmem_cache_alloc() Generalize the code to use the statically-allocated handler for the first registration, regardless of priority. Check .sys_off_cb for conflicts instead of .cb_data; some callbacks (e.g. firmware) do not need any per-instance data, so .cb_data could be NULL. Signed-off-by: Samuel Holland Reviewed-by: Dmitry Osipenko --- kernel/reboot.c | 10 ++++------ 1 file changed, 4 insertions(+), 6 deletions(-) diff --git a/kernel/reboot.c b/kernel/reboot.c index 3bba88c7ffc6..38c18d4f0a36 100644 --- a/kernel/reboot.c +++ b/kernel/reboot.c @@ -327,7 +327,7 @@ static int sys_off_notify(struct notifier_block *nb, return handler->sys_off_cb(&data); } =20 -static struct sys_off_handler platform_sys_off_handler; +static struct sys_off_handler early_sys_off_handler; =20 static struct sys_off_handler *alloc_sys_off_handler(int priority) { @@ -338,10 +338,8 @@ static struct sys_off_handler *alloc_sys_off_handler(i= nt priority) * Platforms like m68k can't allocate sys_off handler dynamically * at the early boot time because memory allocator isn't available yet. */ - if (priority =3D=3D SYS_OFF_PRIO_PLATFORM) { - handler =3D &platform_sys_off_handler; - if (handler->cb_data) - return ERR_PTR(-EBUSY); + if (!early_sys_off_handler.sys_off_cb) { + handler =3D &early_sys_off_handler; } else { if (system_state > SYSTEM_RUNNING) flags =3D GFP_ATOMIC; @@ -358,7 +356,7 @@ static struct sys_off_handler *alloc_sys_off_handler(in= t priority) =20 static void free_sys_off_handler(struct sys_off_handler *handler) { - if (handler =3D=3D &platform_sys_off_handler) + if (handler =3D=3D &early_sys_off_handler) memset(handler, 0, sizeof(*handler)); else kfree(handler); --=20 2.37.3