From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mark yao Subject: Re: [PATCH] drm/rockchip: cancel pending vblanks on close Date: Mon, 14 Mar 2016 10:40:06 +0800 Message-ID: <56E62486.7050700@rock-chips.com> References: <1457716877-427-1-git-send-email-john@metanate.com> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8"; Format="flowed" Content-Transfer-Encoding: base64 Return-path: In-Reply-To: <1457716877-427-1-git-send-email-john@metanate.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" To: John Keeping Cc: linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, linux-rockchip@lists.infradead.org, linux-arm-kernel@lists.infradead.org List-Id: linux-rockchip.vger.kernel.org T24gMjAxNuW5tDAz5pyIMTLml6UgMDE6MjEsIEpvaG4gS2VlcGluZyB3cm90ZToKPiBXaGVuIGNs b3NpbmcgdGhlIERSTSBkZXZpY2Ugd2hpbGUgYSB2YmxhbmsgaXMgcGVuZGluZywgd2UgYWNjZXNz Cj4gZmlsZV9wcml2IGFmdGVyIGl0IGhhcyBiZWVuIGZyZWUnZCwgd2hpY2ggZ2l2ZXM6Cj4KPiAg ICBVbmFibGUgdG8gaGFuZGxlIGtlcm5lbCBOVUxMIHBvaW50ZXIgZGVyZWZlcmVuY2UgYXQgdmly dHVhbCBhZGRyZXNzIDAwMDAwMDAwCj4gICAgLi4uCj4gICAgUEMgaXMgYXQgX19saXN0X2FkZCsw eDVjLzB4ZTgKPiAgICBMUiBpcyBhdCBzZW5kX3ZibGFua19ldmVudCsweDU0LzB4MWYwCj4gICAg Li4uCj4gICAgWzxjMDI5NTJlOD5dIChfX2xpc3RfYWRkKSBmcm9tIFs8YzAzMWE3YjQ+XSAoc2Vu ZF92YmxhbmtfZXZlbnQrMHg1NC8weDFmMCkKPiAgICBbPGMwMzFhNzYwPl0gKHNlbmRfdmJsYW5r X2V2ZW50KSBmcm9tIFs8YzAzMWE5YzA+XSAoZHJtX3NlbmRfdmJsYW5rX2V2ZW50KzB4NzAvMHg3 OCkKPiAgICBbPGMwMzFhOTUwPl0gKGRybV9zZW5kX3ZibGFua19ldmVudCkgZnJvbSBbPGMwMzFh OWY4Pl0gKGRybV9jcnRjX3NlbmRfdmJsYW5rX2V2ZW50KzB4MzAvMHgzNCkKPiAgICBbPGMwMzFh OWM4Pl0gKGRybV9jcnRjX3NlbmRfdmJsYW5rX2V2ZW50KSBmcm9tIFs8YzAzMzlhZDg+XSAodm9w X2lzcisweDIyNC8weDI4YykKPiAgICBbPGMwMzM5OGI0Pl0gKHZvcF9pc3IpIGZyb20gWzxjMDA4 MTc4MD5dIChoYW5kbGVfaXJxX2V2ZW50X3BlcmNwdSsweDEyYy8weDNlNCkKPgo+IFRoaXMgY2Fu IGJlIHRyaWdnZXJlZCBzb21ld2hhdCByZWxpYWJseSB3aXRoOgo+Cj4gCW1vZGV0ZXN0IC1NIHJv Y2tjaGlwIC12IC1zIC4uLgo+Cj4gQWRkIGEgcHJlY2xvc2UgaG9vayB0byB0aGUgZHJpdmVyIHNv IHRoYXQgd2UgY2FuIGRpc2NhcmQgYW55IHBlbmRpbmcKPiB2YmxhbmsgZXZlbnRzIHdoZW4gdGhl IGRldmljZSBpcyBjbG9zZWQuCj4KPiBTaWduZWQtb2ZmLWJ5OiBKb2huIEtlZXBpbmcgPGpvaG5A bWV0YW5hdGUuY29tPgoKTG9va3MgZ29vZCBmb3IgbWUsIGFwcGxpZWQgaW50byBteSBkcm0tZml4 ZXMuCgpUaGFua3MgZm9yIHRoZSBmaXguCgotLSAK77ytYXJrIFlhbwoKCl9fX19fX19fX19fX19f X19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fCmRyaS1kZXZlbCBtYWlsaW5nIGxpc3QK ZHJpLWRldmVsQGxpc3RzLmZyZWVkZXNrdG9wLm9yZwpodHRwczovL2xpc3RzLmZyZWVkZXNrdG9w Lm9yZy9tYWlsbWFuL2xpc3RpbmZvL2RyaS1kZXZlbAo= From mboxrd@z Thu Jan 1 00:00:00 1970 From: mark.yao@rock-chips.com (Mark yao) Date: Mon, 14 Mar 2016 10:40:06 +0800 Subject: [PATCH] drm/rockchip: cancel pending vblanks on close In-Reply-To: <1457716877-427-1-git-send-email-john@metanate.com> References: <1457716877-427-1-git-send-email-john@metanate.com> Message-ID: <56E62486.7050700@rock-chips.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 2016?03?12? 01:21, John Keeping wrote: > When closing the DRM device while a vblank is pending, we access > file_priv after it has been free'd, which gives: > > Unable to handle kernel NULL pointer dereference at virtual address 00000000 > ... > PC is at __list_add+0x5c/0xe8 > LR is at send_vblank_event+0x54/0x1f0 > ... > [] (__list_add) from [] (send_vblank_event+0x54/0x1f0) > [] (send_vblank_event) from [] (drm_send_vblank_event+0x70/0x78) > [] (drm_send_vblank_event) from [] (drm_crtc_send_vblank_event+0x30/0x34) > [] (drm_crtc_send_vblank_event) from [] (vop_isr+0x224/0x28c) > [] (vop_isr) from [] (handle_irq_event_percpu+0x12c/0x3e4) > > This can be triggered somewhat reliably with: > > modetest -M rockchip -v -s ... > > Add a preclose hook to the driver so that we can discard any pending > vblank events when the device is closed. > > Signed-off-by: John Keeping Looks good for me, applied into my drm-fixes. Thanks for the fix. -- ?ark Yao From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754574AbcCNCkU (ORCPT ); Sun, 13 Mar 2016 22:40:20 -0400 Received: from regular1.263xmail.com ([211.150.99.135]:42447 "EHLO regular1.263xmail.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754254AbcCNCkQ (ORCPT ); Sun, 13 Mar 2016 22:40:16 -0400 X-263anti-spam: KSV:0;BIG:0;ABS:1;DNS:0;ATT:0;SPF:S; X-MAIL-GRAY: 0 X-MAIL-DELIVERY: 1 X-KSVirus-check: 0 X-ABS-CHECKED: 1 X-SKE-CHECKED: 1 X-ADDR-CHECKED: 0 X-RL-SENDER: mark.yao@rock-chips.com X-FST-TO: linux-kernel@vger.kernel.org X-SENDER-IP: 58.22.7.114 X-LOGIN-NAME: mark.yao@rock-chips.com X-UNIQUE-TAG: X-ATTACHMENT-NUM: 0 X-DNS-TYPE: 0 Message-ID: <56E62486.7050700@rock-chips.com> Date: Mon, 14 Mar 2016 10:40:06 +0800 From: Mark yao User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.8.0 MIME-Version: 1.0 To: John Keeping CC: David Airlie , Heiko Stuebner , dri-devel@lists.freedesktop.org, linux-arm-kernel@lists.infradead.org, linux-rockchip@lists.infradead.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] drm/rockchip: cancel pending vblanks on close References: <1457716877-427-1-git-send-email-john@metanate.com> In-Reply-To: <1457716877-427-1-git-send-email-john@metanate.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2016年03月12日 01:21, John Keeping wrote: > When closing the DRM device while a vblank is pending, we access > file_priv after it has been free'd, which gives: > > Unable to handle kernel NULL pointer dereference at virtual address 00000000 > ... > PC is at __list_add+0x5c/0xe8 > LR is at send_vblank_event+0x54/0x1f0 > ... > [] (__list_add) from [] (send_vblank_event+0x54/0x1f0) > [] (send_vblank_event) from [] (drm_send_vblank_event+0x70/0x78) > [] (drm_send_vblank_event) from [] (drm_crtc_send_vblank_event+0x30/0x34) > [] (drm_crtc_send_vblank_event) from [] (vop_isr+0x224/0x28c) > [] (vop_isr) from [] (handle_irq_event_percpu+0x12c/0x3e4) > > This can be triggered somewhat reliably with: > > modetest -M rockchip -v -s ... > > Add a preclose hook to the driver so that we can discard any pending > vblank events when the device is closed. > > Signed-off-by: John Keeping Looks good for me, applied into my drm-fixes. Thanks for the fix. -- Ｍark Yao