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 004BCC3527C for ; Tue, 12 Apr 2022 07:05:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1352704AbiDLHFw (ORCPT ); Tue, 12 Apr 2022 03:05:52 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48054 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1351723AbiDLGyQ (ORCPT ); Tue, 12 Apr 2022 02:54:16 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 55B7C38BC6; Mon, 11 Apr 2022 23:43:42 -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 DC3C960B5E; Tue, 12 Apr 2022 06:43:41 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id E66ECC385A6; Tue, 12 Apr 2022 06:43:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1649745821; bh=coE8RsUUJYW+3vi9y+Ncnu7S2AgcCtQ2sAsW9PxyBPQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=XpEiFoRfLOhX0T4m71TLOe+xxYUDoANIUFH9ImSy8otxVQs8m8kuBxQJZ3aIgjqmF BGN7j7H+xZS7eCJs2mThepqixF6HQW56y2uFYCNitRZUGcNBE0A5el5mc4zbF2h/Dn xZAT8MLGRIH3YocXzSEUNnlqjlFHuMk6dFOym7bg= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Daniel Thompson , Dmitry Baryshkov , Sasha Levin Subject: [PATCH 5.15 061/277] drm/msm/dsi: Remove spurious IRQF_ONESHOT flag Date: Tue, 12 Apr 2022 08:27:44 +0200 Message-Id: <20220412062943.814409574@linuxfoundation.org> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20220412062942.022903016@linuxfoundation.org> References: <20220412062942.022903016@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Daniel Thompson [ Upstream commit 24b176d8827d167ac3b379317f60c0985f6e95aa ] Quoting the header comments, IRQF_ONESHOT is "Used by threaded interrupts which need to keep the irq line disabled until the threaded handler has been run.". When applied to an interrupt that doesn't request a threaded irq then IRQF_ONESHOT has a lesser known (undocumented?) side effect, which it to disable the forced threading of irqs (and for "normal" kernels it is a nop). In this case I can find no evidence that suppressing forced threading is intentional. Had it been intentional then a driver must adopt the raw_spinlock API in order to avoid deadlocks on PREEMPT_RT kernels (and avoid calling any kernel API that uses regular spinlocks). Fix this by removing the spurious additional flag. This change is required for my Snapdragon 7cx Gen2 tablet to boot-to-GUI with PREEMPT_RT enabled. Signed-off-by: Daniel Thompson Reviewed-by: Dmitry Baryshkov Link: https://lore.kernel.org/r/20220201174734.196718-2-daniel.thompson@linaro.org Signed-off-by: Dmitry Baryshkov Signed-off-by: Sasha Levin --- drivers/gpu/drm/msm/dsi/dsi_host.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/gpu/drm/msm/dsi/dsi_host.c b/drivers/gpu/drm/msm/dsi/dsi_host.c index dc85974c7897..eea679a52e86 100644 --- a/drivers/gpu/drm/msm/dsi/dsi_host.c +++ b/drivers/gpu/drm/msm/dsi/dsi_host.c @@ -1909,7 +1909,7 @@ int msm_dsi_host_init(struct msm_dsi *msm_dsi) /* do not autoenable, will be enabled later */ ret = devm_request_irq(&pdev->dev, msm_host->irq, dsi_host_irq, - IRQF_TRIGGER_HIGH | IRQF_ONESHOT | IRQF_NO_AUTOEN, + IRQF_TRIGGER_HIGH | IRQF_NO_AUTOEN, "dsi_isr", msm_host); if (ret < 0) { dev_err(&pdev->dev, "failed to request IRQ%u: %d\n", -- 2.35.1