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 7C6C0CD3447 for ; Sat, 9 May 2026 08:45:22 +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:Content-Type:MIME-Version: References:In-Reply-To:Subject:Cc:To:From:Message-ID: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=pdIwqFHJus8yHIv6hWPRnSYqUNCgGt6yNEiML7zUeM4=; b=JhXc8LIFQZR1ztWf4Cnl+WQ6pz mL+HpQT44V5be9m0RSae1dNKbOjCbyyTshzSWa7cp4bKBE64wx/LGYifmHGy5xdr9fRMJoZx+AyrR 5NAGmPd0+xbuzWnr9f/QwwHzd0gDsKg/K0wTZY+p77elQzgke1/y8GCkUt0tvDT6avm5VzAyJDoDd vYnXMcLFw8ZKwKPZ+i25tQ9MPuTc5Gs/KeF2yYGLTWfLcPR3u7AGOA9AJXR8RSNumllhZkbWWOeUB +/D3LJ8bcCQOTi6ZwKgc4oDqHv4cu+N5W3YQZ5ztZC4RRhnYd8CmrLjDaj5989dkZTOScjAg0+MAa jP9C648Q==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1wLdJE-00000008c9s-0D4a; Sat, 09 May 2026 08:45:16 +0000 Received: from sea.source.kernel.org ([172.234.252.31]) by bombadil.infradead.org with esmtps (Exim 4.99.1 #2 (Red Hat Linux)) id 1wLdJA-00000008c96-3hwn for linux-arm-kernel@lists.infradead.org; Sat, 09 May 2026 08:45:14 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by sea.source.kernel.org (Postfix) with ESMTP id D6E554166F; Sat, 9 May 2026 08:45:11 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id ACEBEC2BCB2; Sat, 9 May 2026 08:45:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1778316311; bh=VahACnmISsK/pJLBRfVnHq1AO2ulykOODkGw12kjbRk=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=XdL1m73MCKiC/RtCYGcwccNwIKKyrNlf9P7IXPe7Sr39A6ILsf48tUFwds0E6N09p r3grLf/rFS5pULDLweIkbhLKk6K3neT4nFJDCgPUWJUQzVGojOhngff3vh8FhGEfzi nHH/Bt4uNjcuWZ1Aw7URnWN88P5oN8bYDzoAiw9TRA+lFPrfvEtzAwuvppTjQKtrRg ThPYPJvrebtmFdYv0KzW+OPkyHYUrimlfPdvLeRWcyQVQHN/0W7+m8m/6wWqSfs2RO CpufGG+qSMROyp4sq7g9WVFX5/35ZtcqbV6INmWGUVJWsOzP4vVHFUyEdLlqJ/SjNl rSzn8blnERNig== Received: from sofa.misterjones.org ([185.219.108.64] helo=lobster-girl.misterjones.org) by disco-boy.misterjones.org with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.98.2) (envelope-from ) id 1wLdJ7-00000000aIL-0ODj; Sat, 09 May 2026 08:45:09 +0000 Date: Sat, 09 May 2026 09:45:05 +0100 Message-ID: <87y0ht9dke.wl-maz@kernel.org> From: Marc Zyngier To: Jack Matthews Cc: Mark Rutland , linux-arm-kernel@lists.infradead.org, regressions@lists.linux.dev, linux-kernel@vger.kernel.org, linux-arm-msm@vger.kernel.org Subject: Re: Regression in split ARM MMIO timer driver In-Reply-To: <46A20F89-E208-4091-8B6E-B5C38BF82B42@jackmatthe.ws> References: <46A20F89-E208-4091-8B6E-B5C38BF82B42@jackmatthe.ws> User-Agent: Wanderlust/2.15.9 (Almost Unreal) SEMI-EPG/1.14.7 (Harue) FLIM-LB/1.14.9 (=?UTF-8?B?R29qxY0=?=) APEL-LB/10.8 EasyPG/1.0.0 Emacs/30.1 (aarch64-unknown-linux-gnu) MULE/6.0 (HANACHIRUSATO) MIME-Version: 1.0 (generated by SEMI-EPG 1.14.7 - "Harue") Content-Type: text/plain; charset=US-ASCII X-SA-Exim-Connect-IP: 185.219.108.64 X-SA-Exim-Rcpt-To: jack@jackmatthe.ws, mark.rutland@arm.com, linux-arm-kernel@lists.infradead.org, regressions@lists.linux.dev, linux-kernel@vger.kernel.org, linux-arm-msm@vger.kernel.org X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.9.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260509_014513_013863_2A5485C4 X-CRM114-Status: GOOD ( 25.96 ) X-BeenThere: linux-arm-kernel@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-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Fri, 08 May 2026 20:48:14 +0100, Jack Matthews wrote: > > Hello, > > I am working on mainlining an old chip, Qualcomm's MDM9625 modem. > I had previously booted 6.17-rc3 before putting this project to the > side, but when I restarted work on 7.0 I was unable to boot. > I have bisected this to commit > 0f67b56d84b4c49adfd61f19f81f84ec613ab51a > (https://lore.kernel.org/all/20250814154622.10193-4-maz@kernel.org/) > and reverting this commit makes the device boot > successfully. Unfortunately I do not have access to low level > debugging such as UART so I have not been able to pinpoint exactly > what is missing. > My changes for this chip are all available here in case it is an > issue of my own doing: > https://github.com/jackmthws/linux/commits/mdm9625-latest/ I > apologize if I this isn't the proper way to submit a regression > report, this is my first time doing so. Given that this is not a machine that is supported upstream, this really isn't a regression. Unless of course you can reproduce it on something that is currently supported, and in which case it would absolutely be a regression. I'm afraid that without a boot log, it is going to be difficult to pinpoint what is going wrong here. This is most likely a latent bug either in the MMIO timer driver, or something unexpected in the way the platform is described. Could you start by posting a kernel boot log of 7.0 with this commit reverted? I'm also interested in finding out what happens if you don't revert that commit, but instead comment out the entry in the Makefile for the MMIO driver. Thanks, M. -- Jazz isn't dead. It just smells funny.