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 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id E95CCC7EE31 for ; Fri, 27 Jun 2025 09:58:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=y9vhrsp7QZvTqYOj7ek2BlquX7altZRuzwvy5tsKFHE=; b=C9o1+YXR1ucTkSP0ygkFl+odzJ +0vcJUsLdTzWcy8hVfZJhv6qrgbL66Z7XZYl0jt8fzEtg2NTBDMl8rh+qfQoJLTpuNnEBozAWQ8sM s2CZYALabiwn5JeoGipssg3/t2xNKd7lyyM4+qA4ON8LvdFArWiBT09PHL9k+OjinKSpHLqGWHg6E 57VRzCgyW7X9ltSpB7bbDOYCaVzh7vC5uterj9rnIqyu5nX8xagXlnNkpajQTxsc5nE5VNpX9Ebps PhaaHb3/OcCmlAmPPGvpdGsJzN+cQsMbgRXaB/ZHbwl5rhh20pApFeBoaO+EIEOPj74ILDCTffSsy qa8iAc4Q==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1uV5rC-0000000EBQb-1WoC; Fri, 27 Jun 2025 09:58:54 +0000 Received: from galois.linutronix.de ([193.142.43.55]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1uV5lz-0000000EAlO-2jXF for linux-um@lists.infradead.org; Fri, 27 Jun 2025 09:53:32 +0000 Date: Fri, 27 Jun 2025 11:53:28 +0200 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1751018010; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=y9vhrsp7QZvTqYOj7ek2BlquX7altZRuzwvy5tsKFHE=; b=k2iADpdvrNuJCjXW1lpo4dsA7Opqr7yQ5DO0tTz/zTCDj9UqBrAMwp1OR35WLItIHKLp4S nJH8hw5PiWQgpRqzuC5K6G7k8wEJ5GAhCrojtwwMbiAvMXqEiAhqKoW2TiXbyQb8OpYQE0 73oh0jTNBks9kVXJtgYHY14TdNYiZx7vFefanmvJrDv/pTM/ayYIAZoZNxxlTTW6gI1+Qv epr6XQ7KEh1PYaDKCzWuE5HoZPWRV+tx3veil77Wgs4cnTcNMU6KRGeClvANwmHCCB2twH 53v4yFRh7vlilzAK4cYTEXTL+MXhLGbUfRTkx4D02KGmUz/pg5FdXyQ8VsGtiw== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1751018010; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=y9vhrsp7QZvTqYOj7ek2BlquX7altZRuzwvy5tsKFHE=; b=L9WITtaakBJQMLHa8mH/q+Ou4J2hqnEjRagwucfnjjTG16tO/c8US9UlAUe2TzfS/rvM0w kXbeqk3jtRNVI5BQ== From: Nam Cao To: Johannes Berg Cc: Marc Zyngier , Thomas Gleixner , Richard Weinberger , Anton Ivanov , linux-um@lists.infradead.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 1/1] um: virt-pci: Switch to msi_create_parent_irq_domain() Message-ID: <20250627095328.ce5O9YWf@linutronix.de> References: <45f44f0298259abf1862b965805307b7c01a279d.camel@sipsolutions.net> <20250627084943.nCYOI4Vp@linutronix.de> <94de787f4c3ad6fc3a44c50c2a5d5311861ddd6c.camel@sipsolutions.net> <20250627094901.bkxjYmHj@linutronix.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20250627094901.bkxjYmHj@linutronix.de> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250627_025331_828638_1BF90D77 X-CRM114-Status: UNSURE ( 8.66 ) X-CRM114-Notice: Please train this message. X-BeenThere: linux-um@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-um" Errors-To: linux-um-bounces+linux-um=archiver.kernel.org@lists.infradead.org On Fri, Jun 27, 2025 at 11:49:03AM +0200, Nam Cao wrote: > My understanding of UM is limited, but I think I get it. We dereference a > NULL pointer and get SIGSEGV. We go into that code path and lockdep yells. > > With the NULL pointer deref removed, we won't go into that path, so it > should be good. By "that code path" I mean SIGSEGV handler. Nam