From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 74D8326AC5; Sat, 12 Sep 2026 16:33:53 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789230834; cv=none; b=FlVEgjzBFTsGw2NpoGCgiUN/IIhSedkhRz5eFeu9bY96SaDqxAR1CQhVC2HhbnzhjMV1w2YVEvAoZwD3Tcf86/QPxXXlaHDj2jnuzy7Szmn2Zua9zC5t7OsHt6wOhkwhKd//TTfS5xYk7JVMqk7yTkIt0qTDzT/S0lqX9dVl4eQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789230834; c=relaxed/simple; bh=4N3L0ekzs03w/1/mlF3W6NnFgre/wJD40rhzFiRUl8s=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=jsjGj8F291OzhDxz1Em3Xk2O4ZdXSWElDNpPvk8rMTFw0A2JcCXTEMY3ej3ZYPOa/XA4HA0H7TbIJ+G+moHWQdyj0dvrLu5l3cmZF3VEvYx9GAsIACckJSmLMv/AEog3sk0Btwu0sqLvMaTgpfUYK2hCL7Ady+4Dx0INRQ86Hrw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=zDKWBJD6; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="zDKWBJD6" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 785C61F000FF; Sat, 12 Sep 2026 16:33:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1789230833; bh=MJah2kE923KFfQzEtRLaxErvG8KrA5GG3OViVuXViNM=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=zDKWBJD6J6oQk+ZSnQ1rVQWj/kzMcKRNg/raH2NmBm7TKg9Cm2cHJlL2Qf8NPndFM +QBoi+EIo1txjJSnFRsEWvyTYtTgFHEnCGkxncCEZ0/t/esEo5v60d35VMLenZWv+D jEeAlmbvA/BFwssihU55uQ0UvOYcaAO5ku+ha40U= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Gou Hao , jiazhenyuan , Madhavan Srinivasan , Sasha Levin Subject: [PATCH 6.1 0832/1191] powerpc/smp: add NULL guard for cause_ipi in smp_muxed_ipi_message_pass Date: Sat, 12 Sep 2026 08:59:20 +0200 Message-ID: <20260912065606.949713435@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260912065548.086904252@linuxfoundation.org> References: <20260912065548.086904252@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.1-stable review patch. If anyone has any objections, please let me know. ------------------ From: Gou Hao [ Upstream commit 5aabc192702defb8950e7c81b05c3f4ca8ee43ec ] smp_muxed_ipi_message_pass() calls smp_ops->cause_ipi() without checking whether it has been set. On platforms using muxed IPI (e.g. powernv/pseries), smp_ops->cause_ipi is initialized to NULL in the static smp_ops and only assigned during the platform smp_probe() handler. If the IPI subsystem fails to initialize -- for example when xive_init_ipis() fails and xive_smp_probe() returns an error -- the probe handler returns early and cause_ipi is never set. Any subsequent IPI send (e.g. arch_smp_send_reschedule()) would dereference the NULL pointer. Add a NULL check to avoid the crash in that situation. Fixes: 23d72bfd8f9f ("powerpc: Consolidate ipi message mux and demux") Signed-off-by: Gou Hao Reviewed-by: jiazhenyuan Signed-off-by: Madhavan Srinivasan Link: https://patch.msgid.link/20260727104215.184786-6-gouhao@uniontech.com Signed-off-by: Sasha Levin --- arch/powerpc/kernel/smp.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/arch/powerpc/kernel/smp.c b/arch/powerpc/kernel/smp.c index 24c1950010812..980f2bc832d98 100644 --- a/arch/powerpc/kernel/smp.c +++ b/arch/powerpc/kernel/smp.c @@ -294,6 +294,9 @@ void smp_muxed_ipi_set_message(int cpu, int msg) void smp_muxed_ipi_message_pass(int cpu, int msg) { + if (!smp_ops->cause_ipi) + return; + smp_muxed_ipi_set_message(cpu, msg); /* -- 2.53.0