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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1CB3DC3F6B0 for ; Tue, 26 Jul 2022 17:48:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239531AbiGZRsP (ORCPT ); Tue, 26 Jul 2022 13:48:15 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42424 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233972AbiGZRsN (ORCPT ); Tue, 26 Jul 2022 13:48:13 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C584212A9F; Tue, 26 Jul 2022 10:48:12 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 6091661160; Tue, 26 Jul 2022 17:48:12 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 80B45C433D6; Tue, 26 Jul 2022 17:48:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1658857691; bh=jBQWWYLAlwhQocmCejiAludOWzxiwJJG/jaLDBo9abU=; h=From:To:Cc:Subject:References:Date:In-Reply-To:From; b=JaLKe/taM87sXwV5wgYLDJmRHMRotMw71eAuOWV5JPQFtC9dbG8P98j0vQaf7tELA UhiiM6Qsjg7oz2zdNzGn4Wvr91JKJ9f4F99MdtQlwXdArtoBlxHf2/94oNO5nUSp7I 9413FCmNn8X5AKozZJWEGdfel/SDI/yZqdsNF3/sgLteCKjlEcXe1CSoetGZATQc+Q ph06HgBlXIGdUVYUtP5BgQNbIfwSadrIAr0CDC4mkd2C2Mb8pKqqfVIB8TQkA1+xnz S4QIkjDTMmgXPo2J7uThrqx3Y4fJgYm7QbPEH9D0dLeNdhTQ220KSPebSpSpt1mSuE KbgK2TGJNgxUA== From: Kalle Valo To: Manivannan Sadhasivam Cc: Qiang Yu , quic_hemantk@quicinc.com, loic.poulain@linaro.org, quic_jhugo@quicinc.com, mhi@lists.linux.dev, linux-arm-msm@vger.kernel.org, linux-kernel@vger.kernel.org, quic_cang@quicinc.com, ath11k@lists.infradead.org Subject: Re: [PATCH v4 1/1] bus: mhi: host: Move IRQ allocation to controller registration phase References: <1655952183-66792-1-git-send-email-quic_qianyu@quicinc.com> <20220624072740.GA12171@thinkpad> <87k08an038.fsf@kernel.org> <20220720093909.GA5747@thinkpad> <063fe6bf-11b1-1724-058f-0fed7247906e@quicinc.com> <20220721101914.GC36189@thinkpad> <87wnc1qdhz.fsf@kernel.org> <20220726080913.GF5522@workstation> Date: Tue, 26 Jul 2022 20:48:05 +0300 In-Reply-To: <20220726080913.GF5522@workstation> (Manivannan Sadhasivam's message of "Tue, 26 Jul 2022 13:39:13 +0530") Message-ID: <87h733rciy.fsf@kernel.org> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/26.1 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Manivannan Sadhasivam writes: > On Mon, Jul 25, 2022 at 09:00:08PM +0300, Kalle Valo wrote: > >> Manivannan Sadhasivam writes: >>=20 >> > On Wed, Jul 20, 2022 at 05:47:37PM +0800, Qiang Yu wrote: >> > >> >>=20 >> >> On 7/20/2022 5:39 PM, Manivannan Sadhasivam wrote: >> >> > On Mon, Jul 18, 2022 at 02:15:23PM +0300, Kalle Valo wrote: >> >> > > + ath11k list >> >> > >=20 >> >> > > Manivannan Sadhasivam writes: >> >> > >=20 >> >> > > > On Thu, Jun 23, 2022 at 10:43:03AM +0800, Qiang Yu wrote: >> >> > > > > During runtime, the MHI endpoint may be powered up/down sever= al times. >> >> > > > > So instead of allocating and destroying the IRQs all the time= , let's just >> >> > > > > enable/disable IRQs during power up/down. >> >> > > > >=20 >> >> > > > > The IRQs will be allocated during mhi_register_controller() a= nd freed >> >> > > > > during mhi_unregister_controller(). This works well for thing= s like PCI >> >> > > > > hotplug also as once the PCI device gets removed, the control= ler will >> >> > > > > get unregistered. And once it comes back, it will get registe= red back >> >> > > > > and even if the IRQ configuration changes (MSI), that will ge= t accounted. >> >> > > > >=20 >> >> > > > > Signed-off-by: Qiang Yu >> >> > > > Applied to mhi-next! >> >> > > I did a bisect and this patch breaks ath11k during rmmod. I'm on >> >> > > vacation right now so I can't investigate in detail but more info= below. >> >> > >=20 >> >> > I just tested linux-next/master next-20220718 on my NUC with QCA639= 0, but I'm >> >> > not able to reproduce the issue during rmmod! Instead I couldn't co= nnect to AP. >> >>=20 >> >> I suspect that in __free_irq(), if CONFIG_DEBUG_SHIRQ is enabled, irq >> >> handler for a shared IRQ will be invoked and null pointer access happ= en. >> >>=20 >> >> #ifdef CONFIG_DEBUG_SHIRQ >> >> =C2=A0=C2=A0 =C2=A0/* >> >> =C2=A0=C2=A0 =C2=A0 * It's a shared IRQ -- the driver ought to be pre= pared for an IRQ >> >> =C2=A0=C2=A0 =C2=A0 * event to happen even now it's being freed, so l= et's make sure that >> >> =C2=A0=C2=A0 =C2=A0 * is so by doing an extra call to the handler .... >> >> =C2=A0=C2=A0 =C2=A0 * >> >> =C2=A0=C2=A0 =C2=A0 * ( We do this after actually deregistering it, t= o make sure that a >> >> =C2=A0=C2=A0 =C2=A0 *=C2=A0=C2=A0 'real' IRQ doesn't run in parallel = with our fake. ) >> >> =C2=A0=C2=A0 =C2=A0 */ >> >> =C2=A0=C2=A0 =C2=A0if (action->flags & IRQF_SHARED) { >> >> =C2=A0=C2=A0 =C2=A0=C2=A0=C2=A0=C2=A0 local_irq_save(flags); >> >> =C2=A0=C2=A0 =C2=A0=C2=A0=C2=A0=C2=A0 action->handler(irq, dev_id); >> >> =C2=A0=C2=A0 =C2=A0=C2=A0=C2=A0=C2=A0 local_irq_restore(flags); >> >> =C2=A0=C2=A0 =C2=A0} >> >> #endif >> >>=20 >> > >> > Ah yes, after enabling CONFIG_DEBUG_SHIRQ I could reproduce the issue. >>=20 >> So how to fix this regression? (If there's already a fix I might have >> missed it as I came back only today) >>=20 > > Copied you on the fix patch. Please test and let us know! Thanks, testing it right now. Will let you know the result as a reply to the patch. --=20 https://patchwork.kernel.org/project/linux-wireless/list/ https://wireless.wiki.kernel.org/en/developers/documentation/submittingpatc= hes