From mboxrd@z Thu Jan 1 00:00:00 1970 From: Colin Ian King Subject: Re: [PATCH] drm/amd/amdgpu: default to zero number of states if not enabled Date: Thu, 6 Oct 2016 20:05:58 +0100 Message-ID: <57F6A096.9040701@canonical.com> References: <20161006180211.31747-1-colin.king@canonical.com> <57F6A01D.10907@canonical.com> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Return-path: Received: from youngberry.canonical.com (youngberry.canonical.com [91.189.89.112]) by gabe.freedesktop.org (Postfix) with ESMTPS id DB9276E9E3 for ; Thu, 6 Oct 2016 19:06:00 +0000 (UTC) In-Reply-To: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" To: "Deucher, Alexander" , Alex Deucher Cc: "StDenis, Tom" , "Zhou, Jammy" , LKML , Maling list - DRI developers , "Huang, JinHuiEric" , "Zhu, Rex" , "Koenig, Christian" , Dan Carpenter List-Id: dri-devel@lists.freedesktop.org T24gMDYvMTAvMTYgMjA6MDQsIERldWNoZXIsIEFsZXhhbmRlciB3cm90ZToKPj4gLS0tLS1Pcmln aW5hbCBNZXNzYWdlLS0tLS0KPj4gRnJvbTogQ29saW4gSWFuIEtpbmcgW21haWx0bzpjb2xpbi5r aW5nQGNhbm9uaWNhbC5jb21dCj4+IFNlbnQ6IFRodXJzZGF5LCBPY3RvYmVyIDA2LCAyMDE2IDM6 MDQgUE0KPj4gVG86IEFsZXggRGV1Y2hlcgo+PiBDYzogRGV1Y2hlciwgQWxleGFuZGVyOyBLb2Vu aWcsIENocmlzdGlhbjsgRGF2aWQgQWlybGllOyBIdWFuZywgSmluSHVpRXJpYzsKPj4gWmh1LCBS ZXg7IFpob3UsIEphbW15OyBTdERlbmlzLCBUb207IERhbiBDYXJwZW50ZXI7IE1hbGluZyBsaXN0 IC0gRFJJCj4+IGRldmVsb3BlcnM7IExLTUwKPj4gU3ViamVjdDogUmU6IFtQQVRDSF0gZHJtL2Ft ZC9hbWRncHU6IGRlZmF1bHQgdG8gemVybyBudW1iZXIgb2Ygc3RhdGVzIGlmCj4+IG5vdCBlbmFi bGVkCj4+Cj4+IE9uIDA2LzEwLzE2IDE5OjMyLCBBbGV4IERldWNoZXIgd3JvdGU6Cj4+PiBPbiBU aHUsIE9jdCA2LCAyMDE2IGF0IDI6MDIgUE0sIENvbGluIEtpbmcgPGNvbGluLmtpbmdAY2Fub25p Y2FsLmNvbT4KPj4gd3JvdGU6Cj4+Pj4gRnJvbTogQ29saW4gSWFuIEtpbmcgPGNvbGluLmtpbmdA Y2Fub25pY2FsLmNvbT4KPj4+Pgo+Pj4+IEN1cnJlbnRseSwgaWYgYWRldi0+cHBfZW5hYmxlZCBp cyBmYWxzZSB0aGVuIHRoZSBwcF9zdGF0c19pbmZvIGRhdGEKPj4+PiBpcyBub3QgcmVhZCBhbmQg aGVuY2UgYSBnYXJiYWdlIG51bWJlciBvZiBzdGF0ZXMgZnJvbSB0aGUgc3RhY2sKPj4+PiBpcyB1 c2VkIHRvIGR1bXAgb3V0IHRoZSBudW1iZXIgb2Ygc3RhdGVzLiBHaXZlbiBkYXRhLm51bXMgY291 bGQgYmUKPj4+PiBhbnkgcmFuZG9tIHZhbHVlLCB0aGlzIGNvdWxkIGVhc2lseSBsZWFkIHRvIHJl YWQgb3V0c2lkZSB0aGUKPj4+PiBkYXRhLnN0YXRlcyBhcnJheS4gIEZpeCB0aGlzIGJ5IHNldHRp bmcgZGF0YS5udW1zIHRvIHplcm8gaWYKPj4+PiBhZGV2LT5wcF9lbmFibGVkIGlzIGZhbHNlLgo+ Pj4KPj4+IEFyZSB5b3UgYWN0dWFsbHkgc2VlaW5nIGEgcHJvYmxlbT8KPj4KPj4gTm9wZS4KPj4K Pj4+IFRoZSBwcF9udW1fc3RhdGVzIGF0dHJpYnV0ZSBvbmx5Cj4+PiBnZXRzIGFkZGVkIGluIHRo ZSBmaXJzdCBwbGFjZSBpZiBwcF9lbmFibGVkIGlzIHRydWUuCj4+Cj4+IERvZXMgdGhhdCBtZWFu IHRoYXQgdGhlIGNoZWNrIG9uIGFkZXYtPnBwX2VuYWJsZWQgaXMgcmVkdW5kYW50IHRoZW4/Cj4g Cj4gWWVzLCBJIHRoaW5rIHNvLgoKT0ssIGluIHdoaWNoIGNhc2UgaXQncyBwcm9iYWJseSBleHRy YW5lb3VzIGNvZGUgdGhhdCBjb3VsZCBiZSByZW1vdmVkLgo+IAo+IEFsZXgKPiAKPj4KPj4+Cj4+ PiBBbGV4Cj4+Cj4+Pgo+Pj4+Cj4+Pj4gU2lnbmVkLW9mZi1ieTogQ29saW4gSWFuIEtpbmcgPGNv bGluLmtpbmdAY2Fub25pY2FsLmNvbT4KPj4+PiAtLS0KPj4+PiAgZHJpdmVycy9ncHUvZHJtL2Ft ZC9hbWRncHUvYW1kZ3B1X3BtLmMgfCAyICsrCj4+Pj4gIDEgZmlsZSBjaGFuZ2VkLCAyIGluc2Vy dGlvbnMoKykKPj4+Pgo+Pj4+IGRpZmYgLS1naXQgYS9kcml2ZXJzL2dwdS9kcm0vYW1kL2FtZGdw dS9hbWRncHVfcG0uYwo+PiBiL2RyaXZlcnMvZ3B1L2RybS9hbWQvYW1kZ3B1L2FtZGdwdV9wbS5j Cj4+Pj4gaW5kZXggYWNjYzkwOC4uODA4ZDc4OCAxMDA2NDQKPj4+PiAtLS0gYS9kcml2ZXJzL2dw dS9kcm0vYW1kL2FtZGdwdS9hbWRncHVfcG0uYwo+Pj4+ICsrKyBiL2RyaXZlcnMvZ3B1L2RybS9h bWQvYW1kZ3B1L2FtZGdwdV9wbS5jCj4+Pj4gQEAgLTE5NSw2ICsxOTUsOCBAQCBzdGF0aWMgc3Np emVfdCBhbWRncHVfZ2V0X3BwX251bV9zdGF0ZXMoc3RydWN0Cj4+IGRldmljZSAqZGV2LAo+Pj4+ Cj4+Pj4gICAgICAgICBpZiAoYWRldi0+cHBfZW5hYmxlZCkKPj4+PiAgICAgICAgICAgICAgICAg YW1kZ3B1X2RwbV9nZXRfcHBfbnVtX3N0YXRlcyhhZGV2LCAmZGF0YSk7Cj4+Pj4gKyAgICAgICBl bHNlCj4+Pj4gKyAgICAgICAgICAgICAgIGRhdGEubnVtcyA9IDA7Cj4+Pj4KPj4+PiAgICAgICAg IGJ1Zl9sZW4gPSBzbnByaW50ZihidWYsIFBBR0VfU0laRSwgInN0YXRlczogJWRcbiIsIGRhdGEu bnVtcyk7Cj4+Pj4gICAgICAgICBmb3IgKGkgPSAwOyBpIDwgZGF0YS5udW1zOyBpKyspCj4+Pj4g LS0KPj4+PiAyLjkuMwo+Pj4+Cj4+Pj4gX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19f X19fX19fX19fX19fX18KPj4+PiBkcmktZGV2ZWwgbWFpbGluZyBsaXN0Cj4+Pj4gZHJpLWRldmVs QGxpc3RzLmZyZWVkZXNrdG9wLm9yZwo+Pj4+IGh0dHBzOi8vbGlzdHMuZnJlZWRlc2t0b3Aub3Jn L21haWxtYW4vbGlzdGluZm8vZHJpLWRldmVsCj4gCgpfX19fX19fX19fX19fX19fX19fX19fX19f X19fX19fX19fX19fX19fX19fX19fXwpkcmktZGV2ZWwgbWFpbGluZyBsaXN0CmRyaS1kZXZlbEBs aXN0cy5mcmVlZGVza3RvcC5vcmcKaHR0cHM6Ly9saXN0cy5mcmVlZGVza3RvcC5vcmcvbWFpbG1h bi9saXN0aW5mby9kcmktZGV2ZWwK From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934005AbcJFTGD (ORCPT ); Thu, 6 Oct 2016 15:06:03 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:42374 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751225AbcJFTGA (ORCPT ); Thu, 6 Oct 2016 15:06:00 -0400 Subject: Re: [PATCH] drm/amd/amdgpu: default to zero number of states if not enabled To: "Deucher, Alexander" , Alex Deucher References: <20161006180211.31747-1-colin.king@canonical.com> <57F6A01D.10907@canonical.com> Cc: "Koenig, Christian" , David Airlie , "Huang, JinHuiEric" , "Zhu, Rex" , "Zhou, Jammy" , "StDenis, Tom" , Dan Carpenter , Maling list - DRI developers , LKML From: Colin Ian King Message-ID: <57F6A096.9040701@canonical.com> Date: Thu, 6 Oct 2016 20:05:58 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.6.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 06/10/16 20:04, Deucher, Alexander wrote: >> -----Original Message----- >> From: Colin Ian King [mailto:colin.king@canonical.com] >> Sent: Thursday, October 06, 2016 3:04 PM >> To: Alex Deucher >> Cc: Deucher, Alexander; Koenig, Christian; David Airlie; Huang, JinHuiEric; >> Zhu, Rex; Zhou, Jammy; StDenis, Tom; Dan Carpenter; Maling list - DRI >> developers; LKML >> Subject: Re: [PATCH] drm/amd/amdgpu: default to zero number of states if >> not enabled >> >> On 06/10/16 19:32, Alex Deucher wrote: >>> On Thu, Oct 6, 2016 at 2:02 PM, Colin King >> wrote: >>>> From: Colin Ian King >>>> >>>> Currently, if adev->pp_enabled is false then the pp_stats_info data >>>> is not read and hence a garbage number of states from the stack >>>> is used to dump out the number of states. Given data.nums could be >>>> any random value, this could easily lead to read outside the >>>> data.states array. Fix this by setting data.nums to zero if >>>> adev->pp_enabled is false. >>> >>> Are you actually seeing a problem? >> >> Nope. >> >>> The pp_num_states attribute only >>> gets added in the first place if pp_enabled is true. >> >> Does that mean that the check on adev->pp_enabled is redundant then? > > Yes, I think so. OK, in which case it's probably extraneous code that could be removed. > > Alex > >> >>> >>> Alex >> >>> >>>> >>>> Signed-off-by: Colin Ian King >>>> --- >>>> drivers/gpu/drm/amd/amdgpu/amdgpu_pm.c | 2 ++ >>>> 1 file changed, 2 insertions(+) >>>> >>>> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_pm.c >> b/drivers/gpu/drm/amd/amdgpu/amdgpu_pm.c >>>> index accc908..808d788 100644 >>>> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_pm.c >>>> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_pm.c >>>> @@ -195,6 +195,8 @@ static ssize_t amdgpu_get_pp_num_states(struct >> device *dev, >>>> >>>> if (adev->pp_enabled) >>>> amdgpu_dpm_get_pp_num_states(adev, &data); >>>> + else >>>> + data.nums = 0; >>>> >>>> buf_len = snprintf(buf, PAGE_SIZE, "states: %d\n", data.nums); >>>> for (i = 0; i < data.nums; i++) >>>> -- >>>> 2.9.3 >>>> >>>> _______________________________________________ >>>> dri-devel mailing list >>>> dri-devel@lists.freedesktop.org >>>> https://lists.freedesktop.org/mailman/listinfo/dri-devel >