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=-0.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS autolearn=no 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 DA428C35280 for ; Thu, 7 May 2020 21:52:03 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id A9FAD20870 for ; Thu, 7 May 2020 21:52:03 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="QwuxCceF" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org A9FAD20870 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linutronix.de Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+infradead-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=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:Message-ID:Date:References :In-Reply-To:Subject:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=MXJvdjRUiCjrHWet8P5D0D0uPNPPLK5WDOSNJJu0BIU=; b=QwuxCceFlTP/35 BBFfxwvLEFUh9ZGBE9VKYZhWoZc/Js8Za9d+QqYrNVe3xRcbnc+az706Y/oRIub/aTiFTBqJkvoT4 LNXSrs1fIAikyDBvVV2NII0KKy0s5PNu4gcvyou77Z5GcxRCLoTauCUH0sKEXi2WP5Rj2FmgG00ER WCNAzvlmxCSC7ba0OT1RogdUXuj/sVqaIbTlQ/QtX+FM4Zq8SRUBuZH+WP1/FbQse0Cq7dxK0csAD jJQAhesGDDYxXdhQZcTABaO1cauw5v9FdyO2wTeKp3WPPkmgp+UBaZQVeLCSre71qG2R3paIhBwmK v171mzYYMycCI9AqjiBQ==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1jWoQy-0007lc-N9; Thu, 07 May 2020 21:52:00 +0000 Received: from galois.linutronix.de ([2a0a:51c0:0:12e:550::1]) by bombadil.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1jWoQv-0007l5-Vz for linux-arm-kernel@lists.infradead.org; Thu, 07 May 2020 21:51:59 +0000 Received: from p5de0bf0b.dip0.t-ipconnect.de ([93.224.191.11] helo=nanos.tec.linutronix.de) by Galois.linutronix.de with esmtpsa (TLS1.2:DHE_RSA_AES_256_CBC_SHA256:256) (Exim 4.80) (envelope-from ) id 1jWoQp-00079V-W0; Thu, 07 May 2020 23:51:52 +0200 Received: by nanos.tec.linutronix.de (Postfix, from userid 1000) id 46CA0102652; Thu, 7 May 2020 23:51:51 +0200 (CEST) From: Thomas Gleixner To: Marek Vasut , linux-arm-kernel@lists.infradead.org Subject: Re: [PATCH] [RFC] genirq: Check irq_data_get_irq_chip() return value before use In-Reply-To: <05c06df8-f871-c20f-3b7e-bcfa0b5d88cd@denx.de> References: <20200507150729.244468-1-marex@denx.de> <87r1vvejqa.fsf@nanos.tec.linutronix.de> <05c06df8-f871-c20f-3b7e-bcfa0b5d88cd@denx.de> Date: Thu, 07 May 2020 23:51:51 +0200 Message-ID: <875zd7e7m0.fsf@nanos.tec.linutronix.de> MIME-Version: 1.0 X-Linutronix-Spam-Score: -1.0 X-Linutronix-Spam-Level: - X-Linutronix-Spam-Status: No , -1.0 points, 5.0 required, ALL_TRUSTED=-1, SHORTCIRCUIT=-0.0001 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200507_145158_171753_CB68463B X-CRM114-Status: GOOD ( 14.78 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Marc Zyngier , Linus Walleij , Stephen Boyd Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org Marek, Marek Vasut writes: > On 5/7/20 7:30 PM, Thomas Gleixner wrote: >> Marek Vasut writes: >>> NOTE: I don't know whether this is a correct fix. Maybe the >>> irq_data_get_irq_chip() should never return NULL, and >>> I have some other issue? >> >> What's the callchain? > > Hmm, I'm currently unable to replicate it on linux-next, but on 5.4.39 I > get what's at the end of the email. > > On next I just noticed I get i2c: Transfer while suspended, which is > what I suspect would be the real root cause of my problem, and why > irq_data_get_irq_chip() returns NULL? Looks like. > Unable to handle kernel NULL pointer dereference at virtual address 00000070 > PC is at __irq_get_irqchip_state+0x4/0x30 > LR is at __synchronize_hardirq+0x7c/0xe8 > [] (__irq_get_irqchip_state) from [] (__synchronize_hardirq+0x7c/0xe8) > [] (__synchronize_hardirq) from [] (synchronize_irq+0x2c/0x9c) > [] (synchronize_irq) from [] (suspend_device_irqs+0xd8/0xf4) > [] (suspend_device_irqs) from [] (dpm_suspend_noirq+0x18/0x194) > [] (dpm_suspend_noirq) from [] (suspend_devices_and_enter+0x170/0x514) > [] (suspend_devices_and_enter) from [] (pm_suspend+0x1dc/0x278) > [] (pm_suspend) from [] (state_store+0x9c/0xcc) > [] (state_store) from [] (kernfs_fop_write+0x124/0x1e0) > [] (kernfs_fop_write) from [] (__vfs_write+0x2c/0xe8) > [] (__vfs_write) from [] (vfs_write+0x98/0xbc) > [] (vfs_write) from [] (ksys_write+0x74/0xc4) > [] (ksys_write) from [] (ret_fast_syscall+0x0/0x54) I assume that the i2c controller in question tears down the interrupt on suspend. The changelog of that i2c driver should give you a few hints. Thanks, tglx _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel