From mboxrd@z Thu Jan 1 00:00:00 1970 From: Joonas Lahtinen Subject: Re: [Intel-gfx] [PATCH] drm: Release driver tracking before making the object available again Date: Tue, 22 Aug 2017 16:20:22 +0300 Message-ID: <1503408022.9954.19.camel@linux.intel.com> References: <20170819120558.6465-1-chris@chris-wilson.co.uk> <20170821161624.myaqrevhuyrxcvj7@phenom.ffwll.local> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Return-path: In-Reply-To: <20170821161624.myaqrevhuyrxcvj7@phenom.ffwll.local> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" To: Daniel Vetter , Chris Wilson , Sean Paul Cc: intel-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org, stable@vger.kernel.org, Daniel Vetter , Thierry Reding List-Id: dri-devel@lists.freedesktop.org KyBTZWFuCgpPbiBNb24sIDIwMTctMDgtMjEgYXQgMTg6MTYgKzAyMDAsIERhbmllbCBWZXR0ZXIg d3JvdGU6Cj4gT24gU2F0LCBBdWcgMTksIDIwMTcgYXQgMDE6MDU6NThQTSArMDEwMCwgQ2hyaXMg V2lsc29uIHdyb3RlOgo+ID4gVGhpcyBpcyB0aGUgc2FtZSBidWcgYXMgd2UgZml4ZWQgaW4gY29t bWl0IGY2Y2Q3ZGFlY2ZmNSAoImRybTogUmVsZWFzZQo+ID4gZHJpdmVyIHJlZmVyZW5jZXMgdG8g aGFuZGxlIGJlZm9yZSBtYWtpbmcgaXQgYXZhaWxhYmxlIGFnYWluIiksIGJ1dCBub3cKPiA+IHRo ZSBleHBvc3VyZSBpcyB2aWEgdGhlIFBSSU1FIGxvb2t1cCB0YWJsZXMuIElmIHdlIHJlbW92ZSB0 aGUKPiA+IG9iamVjdC9oYW5kbGUgZnJvbSB0aGUgUFJJTUUgbHV0LCB0aGVuIGEgbmV3IHJlcXVl c3QgZm9yIHRoZSBzYW1lCj4gPiBvYmplY3QvZmQgd2lsbCBnZW5lcmF0ZSBhIG5ldyBoYW5kbGUs IHRodXMgZm9yIGEgc2hvcnQgd2luZG93IHRoYXQKPiA+IG9iamVjdCBpcyBrbm93biB0byB1c2Vy c3BhY2UgYnkgdHdvIGRpZmZlcmVudCBoYW5kbGVzLiBGaXggdGhpcyBieQo+ID4gcmVsZWFzaW5n IHRoZSBkcml2ZXIgdHJhY2tpbmcgYmVmb3JlIFBSSU1FLgo+ID4gCj4gPiBGaXhlczogMGZmOTI2 YzdkNGYwICgiZHJtL3ByaW1lOiBhZGQgZXhwb3J0ZWQgYnVmZmVycyB0byBjdXJyZW50IGZwcml2 cwo+ID4gaW1wb3J0ZWQgYnVmZmVyIGxpc3QgKHYyKSIpCj4gPiBTaWduZWQtb2ZmLWJ5OiBDaHJp cyBXaWxzb24gPGNocmlzQGNocmlzLXdpbHNvbi5jby51az4KPiA+IENjOiBEYXZpZCBBaXJsaWUg PGFpcmxpZWRAbGludXguaWU+Cj4gPiBDYzogRGFuaWVsIFZldHRlciA8ZGFuaWVsLnZldHRlckBp bnRlbC5jb20+Cj4gPiBDYzogUm9iIENsYXJrIDxyb2JkY2xhcmtAZ21haWwuY29tPgo+ID4gQ2M6 IFZpbGxlIFN5cmrDpGzDpCA8dmlsbGUuc3lyamFsYUBsaW51eC5pbnRlbC5jb20+Cj4gPiBDYzog VGhpZXJyeSBSZWRpbmcgPHRyZWRpbmdAbnZpZGlhLmNvbT4KPiA+IENjOiBzdGFibGVAdmdlci5r ZXJuZWwub3JnCj4gCj4gRG8gd2UgaGF2ZSBhbiBldmlsIGlndCBmb3IgdGhpcz8gSSBndWVzcyBz aW5jZSB0aGUgb2xkIG9uZSBkaWRuJ3QgaGF2ZQo+IG9uZSwgdGhpcyBuZXcgcmFjZSBpcyBhbHNv IGhhcmQgdG8gcmVwcm9kdWNlIC4uLgo+IAo+IFJldmlld2VkLWJ5OiBEYW5pZWwgVmV0dGVyIDxk YW5pZWwudmV0dGVyQGZmd2xsLmNoPgoKUHVzaGVkIHRoaXMgdG8gZHJtLW1pc2MtZml4ZXMgKGFu ZCBkcm0tbWlzYy1uZXh0IGZvciBJIGFtIGEgbW9ua2V5IHdpdGgKYSBrZXlib2FyZCksIHRoYW5r cyBmb3IgdGhlIHBhdGNoIGFuZCByZXZpZXcuCgpTZWFuLCB5b3UgY2FuIGJsYW1lIGl0IG9uIG1l IHdoZW4vaWYgdGhlcmUgaXMgdHJvdWJsZSBjYXVzZWQgYnkgdGhlCnBhdGNoIGJlaW5nIGluIGJv dGggYnJhbmNoZXMuIEhvcGVmdWxseSBuZXh0IG1lcmdlIHdpbGwgY2F1c2UgbGVzcwpoZWFkYWNo ZS4KClJlZ2FyZHMsIEpvb25hcwotLSAKSm9vbmFzIExhaHRpbmVuCk9wZW4gU291cmNlIFRlY2hu b2xvZ3kgQ2VudGVyCkludGVsIENvcnBvcmF0aW9uCl9fX19fX19fX19fX19fX19fX19fX19fX19f X19fX19fX19fX19fX19fX19fX19fCmRyaS1kZXZlbCBtYWlsaW5nIGxpc3QKZHJpLWRldmVsQGxp c3RzLmZyZWVkZXNrdG9wLm9yZwpodHRwczovL2xpc3RzLmZyZWVkZXNrdG9wLm9yZy9tYWlsbWFu L2xpc3RpbmZvL2RyaS1kZXZlbAo= From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mga04.intel.com ([192.55.52.120]:4150 "EHLO mga04.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932657AbdHVNUj (ORCPT ); Tue, 22 Aug 2017 09:20:39 -0400 Message-ID: <1503408022.9954.19.camel@linux.intel.com> Subject: Re: [Intel-gfx] [PATCH] drm: Release driver tracking before making the object available again From: Joonas Lahtinen To: Daniel Vetter , Chris Wilson , Sean Paul Cc: David Airlie , intel-gfx@lists.freedesktop.org, stable@vger.kernel.org, dri-devel@lists.freedesktop.org, Daniel Vetter , Thierry Reding Date: Tue, 22 Aug 2017 16:20:22 +0300 In-Reply-To: <20170821161624.myaqrevhuyrxcvj7@phenom.ffwll.local> References: <20170819120558.6465-1-chris@chris-wilson.co.uk> <20170821161624.myaqrevhuyrxcvj7@phenom.ffwll.local> Content-Type: text/plain; charset="UTF-8" Mime-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org List-ID: + Sean On Mon, 2017-08-21 at 18:16 +0200, Daniel Vetter wrote: > On Sat, Aug 19, 2017 at 01:05:58PM +0100, Chris Wilson wrote: > > This is the same bug as we fixed in commit f6cd7daecff5 ("drm: Release > > driver references to handle before making it available again"), but now > > the exposure is via the PRIME lookup tables. If we remove the > > object/handle from the PRIME lut, then a new request for the same > > object/fd will generate a new handle, thus for a short window that > > object is known to userspace by two different handles. Fix this by > > releasing the driver tracking before PRIME. > > > > Fixes: 0ff926c7d4f0 ("drm/prime: add exported buffers to current fprivs > > imported buffer list (v2)") > > Signed-off-by: Chris Wilson > > Cc: David Airlie > > Cc: Daniel Vetter > > Cc: Rob Clark > > Cc: Ville Syrjälä > > Cc: Thierry Reding > > Cc: stable@vger.kernel.org > > Do we have an evil igt for this? I guess since the old one didn't have > one, this new race is also hard to reproduce ... > > Reviewed-by: Daniel Vetter Pushed this to drm-misc-fixes (and drm-misc-next for I am a monkey with a keyboard), thanks for the patch and review. Sean, you can blame it on me when/if there is trouble caused by the patch being in both branches. Hopefully next merge will cause less headache. Regards, Joonas -- Joonas Lahtinen Open Source Technology Center Intel Corporation