From patchwork Sat Oct 1 01:19:03 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Danilo Krummrich X-Patchwork-Id: 12996256 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 gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (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 94816C433FE for ; Sat, 1 Oct 2022 01:19:38 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 4BF7910EE04; Sat, 1 Oct 2022 01:19:34 +0000 (UTC) Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by gabe.freedesktop.org (Postfix) with ESMTPS id DF60B10EE04 for ; Sat, 1 Oct 2022 01:19:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1664587170; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=VOw+nn7ti+m5Q8fWTW3IpLkOdVFAAWp2wbEVH0hCZZg=; b=FYOiL4+pquoGr8fBNj94+zNlgf+Pt4z3Bg+oXJAy32WZLO15ISIAJ/NZWOWZqjGSPxIxYq F6BN3LqDzhzUtWUslmd5Aw2T3PFgxDR+SEMtO9Tmm1OcDI7fsuFDq0uXPXrSvb3XVuXnDJ acj6Oi8cOEipUCXjDH1H0lfbSjYiteo= Received: from mail-ed1-f72.google.com (mail-ed1-f72.google.com [209.85.208.72]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_128_GCM_SHA256) id us-mta-413-dVB-DlQXPfa7MNuPezF0Vg-1; Fri, 30 Sep 2022 21:19:28 -0400 X-MC-Unique: dVB-DlQXPfa7MNuPezF0Vg-1 Received: by mail-ed1-f72.google.com with SMTP id w20-20020a05640234d400b00450f24c8ca6so4622199edc.13 for ; Fri, 30 Sep 2022 18:19:28 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date; bh=VOw+nn7ti+m5Q8fWTW3IpLkOdVFAAWp2wbEVH0hCZZg=; b=06zHC1ClD+K4QZ2yXSTir2IU53zmiYR67f5oUz2iEEzLP2oBu5wY5Ih2a9iMPi/82H hv2KtHhr7zqJeiSnauXppSoP0a3zl24uK4rRYbmuzzIrovN4uCh0ZVljplt0cwGlAbOF y4Ft1YAeyYnnxRgak2WzFb2ejb9ivFRxCyrSjIwrzp5giD+iAbCjnfWUu1dMm3VN0+dV MpP2YpxMOSngu6T2665eqOUuPpANrcjl8orXQrQuOcDiRolQpsK1crXYKf7hgbIhOxJw uDPfPIJ5Q3IXqFid5YcnwwnUvK3BxkrKxcvp9k03+5ZET/6uFGoXcAxnD6eGlnotCP/Z FLbw== X-Gm-Message-State: ACrzQf13VrTBA9qa5uLJ4Fe+8BTbzLy2ZcrIiLyFXTQWhjMpsqImxdCI qe9CKyQl8JcA0c8VeC9r/64TFlg/DM97xy4xWdUH+BD9eJo8Ww1xFPS8LtP660NxLQtuWI9NLRM MkoeUUPJQcb+nbL2VQyzEtXIgkJRr X-Received: by 2002:a05:6402:1f89:b0:453:8093:c4e5 with SMTP id c9-20020a0564021f8900b004538093c4e5mr10144844edc.182.1664587167487; Fri, 30 Sep 2022 18:19:27 -0700 (PDT) X-Google-Smtp-Source: AMsMyM6Cz2MhkPwjR82bZuuI/cuJB5Tw0OCSgZ/P3E5KDFUBi+NqgMptkOjbE77f1V0GFF7/gDVgWg== X-Received: by 2002:a05:6402:1f89:b0:453:8093:c4e5 with SMTP id c9-20020a0564021f8900b004538093c4e5mr10144830edc.182.1664587167242; Fri, 30 Sep 2022 18:19:27 -0700 (PDT) Received: from pollux.redhat.com ([2a02:810d:4b40:2ee8:642:1aff:fe31:a15c]) by smtp.gmail.com with ESMTPSA id c9-20020a17090618a900b007821f4bc328sm1948804ejf.178.2022.09.30.18.19.26 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 30 Sep 2022 18:19:26 -0700 (PDT) From: Danilo Krummrich To: daniel@ffwll.ch, airlied@linux.ie, tzimmermann@suse.de, mripard@kernel.org, liviu.dudau@arm.com, brian.starkey@arm.com Subject: [PATCH drm-misc-next v3 5/7] drm/arm/hdlcd: crtc: protect device resources after removal Date: Sat, 1 Oct 2022 03:19:03 +0200 Message-Id: <20221001011905.433408-6-dakr@redhat.com> X-Mailer: git-send-email 2.37.3 In-Reply-To: <20221001011905.433408-1-dakr@redhat.com> References: <20221001011905.433408-1-dakr@redhat.com> MIME-Version: 1.0 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Danilo Krummrich , linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" (Hardware) resources which are bound to the driver and device lifecycle must not be accessed after the device and driver are unbound. However, the DRM device isn't freed as long as the last user didn't close it, hence userspace can still call into the driver. Therefore protect the critical sections which are accessing those resources with drm_dev_enter() and drm_dev_exit(). Signed-off-by: Danilo Krummrich --- drivers/gpu/drm/arm/hdlcd_crtc.c | 60 +++++++++++++++++++++++++++++--- 1 file changed, 55 insertions(+), 5 deletions(-) diff --git a/drivers/gpu/drm/arm/hdlcd_crtc.c b/drivers/gpu/drm/arm/hdlcd_crtc.c index 1de0f7b23766..7ce88fb6e822 100644 --- a/drivers/gpu/drm/arm/hdlcd_crtc.c +++ b/drivers/gpu/drm/arm/hdlcd_crtc.c @@ -18,6 +18,7 @@ #include #include #include +#include #include #include #include @@ -39,28 +40,50 @@ static void hdlcd_crtc_cleanup(struct drm_crtc *crtc) { struct hdlcd_drm_private *hdlcd = crtc_to_hdlcd_priv(crtc); + int idx; + + if (!drm_dev_enter(crtc->dev, &idx)) + goto cleanup; /* stop the controller on cleanup */ hdlcd_write(hdlcd, HDLCD_REG_COMMAND, 0); + + drm_dev_exit(idx); + +cleanup: drm_crtc_cleanup(crtc); } static int hdlcd_crtc_enable_vblank(struct drm_crtc *crtc) { struct hdlcd_drm_private *hdlcd = crtc_to_hdlcd_priv(crtc); - unsigned int mask = hdlcd_read(hdlcd, HDLCD_REG_INT_MASK); + unsigned int mask; + int idx; + if (!drm_dev_enter(crtc->dev, &idx)) + return -ENODEV; + + mask = hdlcd_read(hdlcd, HDLCD_REG_INT_MASK); hdlcd_write(hdlcd, HDLCD_REG_INT_MASK, mask | HDLCD_INTERRUPT_VSYNC); + drm_dev_exit(idx); + return 0; } static void hdlcd_crtc_disable_vblank(struct drm_crtc *crtc) { struct hdlcd_drm_private *hdlcd = crtc_to_hdlcd_priv(crtc); - unsigned int mask = hdlcd_read(hdlcd, HDLCD_REG_INT_MASK); + unsigned int mask; + int idx; + if (!drm_dev_enter(crtc->dev, &idx)) + return; + + mask = hdlcd_read(hdlcd, HDLCD_REG_INT_MASK); hdlcd_write(hdlcd, HDLCD_REG_INT_MASK, mask & ~HDLCD_INTERRUPT_VSYNC); + + drm_dev_exit(idx); } static const struct drm_crtc_funcs hdlcd_crtc_funcs = { @@ -171,21 +194,33 @@ static void hdlcd_crtc_atomic_enable(struct drm_crtc *crtc, struct drm_atomic_state *state) { struct hdlcd_drm_private *hdlcd = crtc_to_hdlcd_priv(crtc); + int idx; + + if (!drm_dev_enter(crtc->dev, &idx)) + return; clk_prepare_enable(hdlcd->clk); hdlcd_crtc_mode_set_nofb(crtc); hdlcd_write(hdlcd, HDLCD_REG_COMMAND, 1); drm_crtc_vblank_on(crtc); + + drm_dev_exit(idx); } static void hdlcd_crtc_atomic_disable(struct drm_crtc *crtc, struct drm_atomic_state *state) { struct hdlcd_drm_private *hdlcd = crtc_to_hdlcd_priv(crtc); + int idx; + + if (!drm_dev_enter(crtc->dev, &idx)) + return; drm_crtc_vblank_off(crtc); hdlcd_write(hdlcd, HDLCD_REG_COMMAND, 0); clk_disable_unprepare(hdlcd->clk); + + drm_dev_exit(idx); } static enum drm_mode_status hdlcd_crtc_mode_valid(struct drm_crtc *crtc, @@ -193,15 +228,23 @@ static enum drm_mode_status hdlcd_crtc_mode_valid(struct drm_crtc *crtc, { struct hdlcd_drm_private *hdlcd = crtc_to_hdlcd_priv(crtc); long rate, clk_rate = mode->clock * 1000; + enum drm_mode_status status = MODE_OK; + int idx; + + if (!drm_dev_enter(crtc->dev, &idx)) + return MODE_NOCLOCK; rate = clk_round_rate(hdlcd->clk, clk_rate); /* 0.1% seems a close enough tolerance for the TDA19988 on Juno */ if (abs(rate - clk_rate) * 1000 > clk_rate) { /* clock required by mode not supported by hardware */ - return MODE_NOCLOCK; + status = MODE_NOCLOCK; + goto out; } - return MODE_OK; +out: + drm_dev_exit(idx); + return status; } static void hdlcd_crtc_atomic_begin(struct drm_crtc *crtc, @@ -268,10 +311,14 @@ static void hdlcd_plane_atomic_update(struct drm_plane *plane, struct hdlcd_drm_private *hdlcd; u32 dest_h; dma_addr_t scanout_start; + int idx; - if (!fb) + if (!drm_dev_enter(plane->dev, &idx)) return; + if (!fb) + goto out; + dest_h = drm_rect_height(&new_plane_state->dst); scanout_start = drm_fb_dma_get_gem_addr(fb, new_plane_state, 0); @@ -280,6 +327,9 @@ static void hdlcd_plane_atomic_update(struct drm_plane *plane, hdlcd_write(hdlcd, HDLCD_REG_FB_LINE_PITCH, fb->pitches[0]); hdlcd_write(hdlcd, HDLCD_REG_FB_LINE_COUNT, dest_h - 1); hdlcd_write(hdlcd, HDLCD_REG_FB_BASE, scanout_start); + +out: + drm_dev_exit(idx); } static const struct drm_plane_helper_funcs hdlcd_plane_helper_funcs = {