From mboxrd@z Thu Jan 1 00:00:00 1970 From: Daniel Vetter Subject: Re: [PATCH] drm/i915: Fix comparison bug Date: Tue, 29 Sep 2015 09:43:10 +0200 Message-ID: <20150929074310.GC3383@phenom.ffwll.local> References: <1443474531-11560-1-git-send-email-linux@rasmusvillemoes.dk> <87vbatislh.fsf@intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Return-path: Content-Disposition: inline In-Reply-To: <87vbatislh.fsf@intel.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" To: Jani Nikula Cc: David Airlie , intel-gfx@lists.freedesktop.org, Rasmus Villemoes , linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, Daniel Vetter List-Id: dri-devel@lists.freedesktop.org T24gVHVlLCBTZXAgMjksIDIwMTUgYXQgMTA6Mzc6MzBBTSArMDMwMCwgSmFuaSBOaWt1bGEgd3Jv dGU6Cj4gT24gVHVlLCAyOSBTZXAgMjAxNSwgUmFzbXVzIFZpbGxlbW9lcyA8bGludXhAcmFzbXVz dmlsbGVtb2VzLmRrPiB3cm90ZToKPiA+IC0+c3RvbGVuLT5zdGFydCBoYXMgdHlwZSB1NjQgYWth IHVuc2lnbmVkIGxvbmcgbG9uZzsgcmVseWluZyBvbiB0aGUKPiA+IGRpZmZlcmVuY2UgKGVmZmVj dGl2ZWx5IGNhc3QgdG8gaW50KSBmb3Igc29ydGluZyBpcyB3cm9uZy4KPiA+Cj4gPiBJdCB3b3Vs ZG4ndCBiZSBhIHByb2JsZW0gaW4gcHJhY3RpY2UgaWYgdGhlIHZhbHVlcyBjb21wYXJlZCBhcmUg YWx3YXlzCj4gPiB3aXRoaW4gSU5UX01BWCBvZiBlYWNoIG90aGVyIChzbyB0aGF0IHRoZSBkaWZm ZXJlbmNlIGlzIGFjdHVhbGx5Cj4gPiByZXByZXNlbnRhYmxlIGluIGFuIGludCksIGJ1dCA0NDBm ZDUyODNhODcgKCJkcm0vbW06IFN1cHBvcnQgNCBHaUIgYW5kCj4gPiBsYXJnZXIgcmFuZ2VzIikg c3Ryb25nbHkgc3VnZ2VzdHMgdGhhdCdzIG5vdCB0aGUgY2FzZS4KPiA+Cj4gPiBTaWduZWQtb2Zm LWJ5OiBSYXNtdXMgVmlsbGVtb2VzIDxsaW51eEByYXNtdXN2aWxsZW1vZXMuZGs+Cj4gCj4gUmV2 aWV3ZWQtYnk6IEphbmkgTmlrdWxhIDxqYW5pLm5pa3VsYUBpbnRlbC5jb20+Cgpkcm1fbW0gaXMg dGhlIHNoYXJlZCBncHUgbWVtbW9yeSBtYW5hZ2VyLCBidXQgc3RvbGVuIGl0c2VsZiBjYW4gb25s eSBnbyB0bwphYm91dCAxLjVHIGN1cnJlbnRseS4gU28gc2FmZSwgYnV0IEkgbWVyZ2VkIHlvdXIg cGF0Y2ggYW55d2F5IHdpdGggYSBzbWFsbApub3RlIGFkZGVkIGZvciA0LjQuCgpUaGFua3MsIERh bmllbAo+IAo+IAo+ID4gLS0tCj4gPiAgZHJpdmVycy9ncHUvZHJtL2k5MTUvaTkxNV9kZWJ1Z2Zz LmMgfCA2ICsrKysrLQo+ID4gIDEgZmlsZSBjaGFuZ2VkLCA1IGluc2VydGlvbnMoKyksIDEgZGVs ZXRpb24oLSkKPiA+Cj4gPiBkaWZmIC0tZ2l0IGEvZHJpdmVycy9ncHUvZHJtL2k5MTUvaTkxNV9k ZWJ1Z2ZzLmMgYi9kcml2ZXJzL2dwdS9kcm0vaTkxNS9pOTE1X2RlYnVnZnMuYwo+ID4gaW5kZXgg ZTNlYzkwNDkwODFmLi41MjA3ZTY4MWE5ODcgMTAwNjQ0Cj4gPiAtLS0gYS9kcml2ZXJzL2dwdS9k cm0vaTkxNS9pOTE1X2RlYnVnZnMuYwo+ID4gKysrIGIvZHJpdmVycy9ncHUvZHJtL2k5MTUvaTkx NV9kZWJ1Z2ZzLmMKPiA+IEBAIC0yNTgsNyArMjU4LDExIEBAIHN0YXRpYyBpbnQgb2JqX3Jhbmtf Ynlfc3RvbGVuKHZvaWQgKnByaXYsCj4gPiAgCXN0cnVjdCBkcm1faTkxNV9nZW1fb2JqZWN0ICpi ID0KPiA+ICAJCWNvbnRhaW5lcl9vZihCLCBzdHJ1Y3QgZHJtX2k5MTVfZ2VtX29iamVjdCwgb2Jq X2V4ZWNfbGluayk7Cj4gPiAgCj4gPiAtCXJldHVybiBhLT5zdG9sZW4tPnN0YXJ0IC0gYi0+c3Rv bGVuLT5zdGFydDsKPiA+ICsJaWYgKGEtPnN0b2xlbi0+c3RhcnQgPCBiLT5zdG9sZW4tPnN0YXJ0 KQo+ID4gKwkJcmV0dXJuIC0xOwo+ID4gKwlpZiAoYS0+c3RvbGVuLT5zdGFydCA+IGItPnN0b2xl bi0+c3RhcnQpCj4gPiArCQlyZXR1cm4gMTsKPiA+ICsJcmV0dXJuIDA7Cj4gPiAgfQo+ID4gIAo+ ID4gIHN0YXRpYyBpbnQgaTkxNV9nZW1fc3RvbGVuX2xpc3RfaW5mbyhzdHJ1Y3Qgc2VxX2ZpbGUg Km0sIHZvaWQgKmRhdGEpCj4gPiAtLSAKPiA+IDIuMS4zCj4gPgo+IAo+IC0tIAo+IEphbmkgTmlr dWxhLCBJbnRlbCBPcGVuIFNvdXJjZSBUZWNobm9sb2d5IENlbnRlcgo+IF9fX19fX19fX19fX19f X19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fCj4gSW50ZWwtZ2Z4IG1haWxpbmcgbGlz dAo+IEludGVsLWdmeEBsaXN0cy5mcmVlZGVza3RvcC5vcmcKPiBodHRwOi8vbGlzdHMuZnJlZWRl c2t0b3Aub3JnL21haWxtYW4vbGlzdGluZm8vaW50ZWwtZ2Z4CgotLSAKRGFuaWVsIFZldHRlcgpT b2Z0d2FyZSBFbmdpbmVlciwgSW50ZWwgQ29ycG9yYXRpb24KaHR0cDovL2Jsb2cuZmZ3bGwuY2gK X19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX18KSW50ZWwtZ2Z4 IG1haWxpbmcgbGlzdApJbnRlbC1nZnhAbGlzdHMuZnJlZWRlc2t0b3Aub3JnCmh0dHA6Ly9saXN0 cy5mcmVlZGVza3RvcC5vcmcvbWFpbG1hbi9saXN0aW5mby9pbnRlbC1nZngK From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755931AbbI2HkU (ORCPT ); Tue, 29 Sep 2015 03:40:20 -0400 Received: from mail-wi0-f182.google.com ([209.85.212.182]:37439 "EHLO mail-wi0-f182.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755776AbbI2HkQ (ORCPT ); Tue, 29 Sep 2015 03:40:16 -0400 Date: Tue, 29 Sep 2015 09:43:10 +0200 From: Daniel Vetter To: Jani Nikula Cc: Rasmus Villemoes , Daniel Vetter , David Airlie , intel-gfx@lists.freedesktop.org, linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org Subject: Re: [Intel-gfx] [PATCH] drm/i915: Fix comparison bug Message-ID: <20150929074310.GC3383@phenom.ffwll.local> Mail-Followup-To: Jani Nikula , Rasmus Villemoes , Daniel Vetter , David Airlie , intel-gfx@lists.freedesktop.org, linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org References: <1443474531-11560-1-git-send-email-linux@rasmusvillemoes.dk> <87vbatislh.fsf@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <87vbatislh.fsf@intel.com> X-Operating-System: Linux phenom 4.1.0-2-amd64 User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Sep 29, 2015 at 10:37:30AM +0300, Jani Nikula wrote: > On Tue, 29 Sep 2015, Rasmus Villemoes wrote: > > ->stolen->start has type u64 aka unsigned long long; relying on the > > difference (effectively cast to int) for sorting is wrong. > > > > It wouldn't be a problem in practice if the values compared are always > > within INT_MAX of each other (so that the difference is actually > > representable in an int), but 440fd5283a87 ("drm/mm: Support 4 GiB and > > larger ranges") strongly suggests that's not the case. > > > > Signed-off-by: Rasmus Villemoes > > Reviewed-by: Jani Nikula drm_mm is the shared gpu memmory manager, but stolen itself can only go to about 1.5G currently. So safe, but I merged your patch anyway with a small note added for 4.4. Thanks, Daniel > > > > --- > > drivers/gpu/drm/i915/i915_debugfs.c | 6 +++++- > > 1 file changed, 5 insertions(+), 1 deletion(-) > > > > diff --git a/drivers/gpu/drm/i915/i915_debugfs.c b/drivers/gpu/drm/i915/i915_debugfs.c > > index e3ec9049081f..5207e681a987 100644 > > --- a/drivers/gpu/drm/i915/i915_debugfs.c > > +++ b/drivers/gpu/drm/i915/i915_debugfs.c > > @@ -258,7 +258,11 @@ static int obj_rank_by_stolen(void *priv, > > struct drm_i915_gem_object *b = > > container_of(B, struct drm_i915_gem_object, obj_exec_link); > > > > - return a->stolen->start - b->stolen->start; > > + if (a->stolen->start < b->stolen->start) > > + return -1; > > + if (a->stolen->start > b->stolen->start) > > + return 1; > > + return 0; > > } > > > > static int i915_gem_stolen_list_info(struct seq_file *m, void *data) > > -- > > 2.1.3 > > > > -- > Jani Nikula, Intel Open Source Technology Center > _______________________________________________ > Intel-gfx mailing list > Intel-gfx@lists.freedesktop.org > http://lists.freedesktop.org/mailman/listinfo/intel-gfx -- Daniel Vetter Software Engineer, Intel Corporation http://blog.ffwll.ch