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=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham 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 27DB4C76195 for ; Fri, 19 Jul 2019 03:58:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E870F21851 for ; Fri, 19 Jul 2019 03:58:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1563508708; bh=guzUZgOKDvGjX7Bi80hdbzQK5EMcnZJJ7C5EuFWknyo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=gvZCpWMbqxN6yNnAry3pGHJ11HE89vQxXzefioSt7K+3eiRaa1NTE7wN3YPV/GTGY UtKHLH2ogwbAqvnScWXlBgzB0qXZ7x4NQtl1DHXecthucH61lHCr2f28h6G6buMG8X wzw+PmRIBTvGcIltiVCP96KAVR5673r7w97u7Kzo= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728072AbfGSD61 (ORCPT ); Thu, 18 Jul 2019 23:58:27 -0400 Received: from mail.kernel.org ([198.145.29.99]:57676 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728003AbfGSD6X (ORCPT ); Thu, 18 Jul 2019 23:58:23 -0400 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 6352021874; Fri, 19 Jul 2019 03:58:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1563508702; bh=guzUZgOKDvGjX7Bi80hdbzQK5EMcnZJJ7C5EuFWknyo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ow8sr7fhJGSmdhbgf4lFiDrdnuPY9eq3TqQrwKtihwr1ygPySzrvKzVaiLxAiHb6R Z7WUGSv/zdK8mwp3lK+br6/Z7WeqMW+PcAEzO2vZLsxVtTrqiqPXDa6rBv/e/oOJf3 PQN4iCPF/79znX2kRBcxNxcOP1oo3jfxaPqLirjM= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Daniel Vetter , Rodrigo Siqueira , Tomeu Vizoso , Emil Velikov , Benjamin Gaignard , =?UTF-8?q?Ville=20Syrj=C3=A4l=C3=A4?= , Daniel Vetter , Sasha Levin , dri-devel@lists.freedesktop.org Subject: [PATCH AUTOSEL 5.2 041/171] drm/crc-debugfs: User irqsafe spinlock in drm_crtc_add_crc_entry Date: Thu, 18 Jul 2019 23:54:32 -0400 Message-Id: <20190719035643.14300-41-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190719035643.14300-1-sashal@kernel.org> References: <20190719035643.14300-1-sashal@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Daniel Vetter [ Upstream commit 1882018a70e06376234133e69ede9dd743b4dbd9 ] We can be called from any context, we need to be prepared. Noticed this while hacking on vkms, which calls this function from a normal worker. Which really upsets lockdep. Cc: Rodrigo Siqueira Cc: Tomeu Vizoso Cc: Emil Velikov Cc: Benjamin Gaignard Reviewed-by: Benjamin Gaignard Reviewed-by: Ville Syrjälä Signed-off-by: Daniel Vetter Link: https://patchwork.freedesktop.org/patch/msgid/20190605194556.16744-1-daniel.vetter@ffwll.ch Signed-off-by: Sasha Levin --- drivers/gpu/drm/drm_debugfs_crc.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/drm_debugfs_crc.c b/drivers/gpu/drm/drm_debugfs_crc.c index 00e743153e94..1a6a5b78e30f 100644 --- a/drivers/gpu/drm/drm_debugfs_crc.c +++ b/drivers/gpu/drm/drm_debugfs_crc.c @@ -389,8 +389,9 @@ int drm_crtc_add_crc_entry(struct drm_crtc *crtc, bool has_frame, struct drm_crtc_crc *crc = &crtc->crc; struct drm_crtc_crc_entry *entry; int head, tail; + unsigned long flags; - spin_lock(&crc->lock); + spin_lock_irqsave(&crc->lock, flags); /* Caller may not have noticed yet that userspace has stopped reading */ if (!crc->entries) { @@ -421,7 +422,7 @@ int drm_crtc_add_crc_entry(struct drm_crtc *crtc, bool has_frame, head = (head + 1) & (DRM_CRC_ENTRIES_NR - 1); crc->head = head; - spin_unlock(&crc->lock); + spin_unlock_irqrestore(&crc->lock, flags); wake_up_interruptible(&crc->wq); -- 2.20.1