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 20:03:57 +0100 Message-ID: <57F6A01D.10907@canonical.com> References: <20161006180211.31747-1-colin.king@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 507676E71D for ; Thu, 6 Oct 2016 19:04:01 +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: Alex Deucher Cc: Tom St Denis , Jammy Zhou , LKML , Maling list - DRI developers , Eric Huang , Alex Deucher , Rex Zhu , =?UTF-8?Q?Christian_K=c3=b6nig?= , Dan Carpenter List-Id: dri-devel@lists.freedesktop.org T24gMDYvMTAvMTYgMTk6MzIsIEFsZXggRGV1Y2hlciB3cm90ZToKPiBPbiBUaHUsIE9jdCA2LCAy MDE2IGF0IDI6MDIgUE0sIENvbGluIEtpbmcgPGNvbGluLmtpbmdAY2Fub25pY2FsLmNvbT4gd3Jv dGU6Cj4+IEZyb206IENvbGluIElhbiBLaW5nIDxjb2xpbi5raW5nQGNhbm9uaWNhbC5jb20+Cj4+ Cj4+IEN1cnJlbnRseSwgaWYgYWRldi0+cHBfZW5hYmxlZCBpcyBmYWxzZSB0aGVuIHRoZSBwcF9z dGF0c19pbmZvIGRhdGEKPj4gaXMgbm90IHJlYWQgYW5kIGhlbmNlIGEgZ2FyYmFnZSBudW1iZXIg b2Ygc3RhdGVzIGZyb20gdGhlIHN0YWNrCj4+IGlzIHVzZWQgdG8gZHVtcCBvdXQgdGhlIG51bWJl ciBvZiBzdGF0ZXMuIEdpdmVuIGRhdGEubnVtcyBjb3VsZCBiZQo+PiBhbnkgcmFuZG9tIHZhbHVl LCB0aGlzIGNvdWxkIGVhc2lseSBsZWFkIHRvIHJlYWQgb3V0c2lkZSB0aGUKPj4gZGF0YS5zdGF0 ZXMgYXJyYXkuICBGaXggdGhpcyBieSBzZXR0aW5nIGRhdGEubnVtcyB0byB6ZXJvIGlmCj4+IGFk ZXYtPnBwX2VuYWJsZWQgaXMgZmFsc2UuCj4gCj4gQXJlIHlvdSBhY3R1YWxseSBzZWVpbmcgYSBw cm9ibGVtPyAgCgpOb3BlLgoKPiBUaGUgcHBfbnVtX3N0YXRlcyBhdHRyaWJ1dGUgb25seQo+IGdl dHMgYWRkZWQgaW4gdGhlIGZpcnN0IHBsYWNlIGlmIHBwX2VuYWJsZWQgaXMgdHJ1ZS4KCkRvZXMg dGhhdCBtZWFuIHRoYXQgdGhlIGNoZWNrIG9uIGFkZXYtPnBwX2VuYWJsZWQgaXMgcmVkdW5kYW50 IHRoZW4/Cgo+IAo+IEFsZXgKCj4gCj4+Cj4+IFNpZ25lZC1vZmYtYnk6IENvbGluIElhbiBLaW5n IDxjb2xpbi5raW5nQGNhbm9uaWNhbC5jb20+Cj4+IC0tLQo+PiAgZHJpdmVycy9ncHUvZHJtL2Ft ZC9hbWRncHUvYW1kZ3B1X3BtLmMgfCAyICsrCj4+ICAxIGZpbGUgY2hhbmdlZCwgMiBpbnNlcnRp b25zKCspCj4+Cj4+IGRpZmYgLS1naXQgYS9kcml2ZXJzL2dwdS9kcm0vYW1kL2FtZGdwdS9hbWRn cHVfcG0uYyBiL2RyaXZlcnMvZ3B1L2RybS9hbWQvYW1kZ3B1L2FtZGdwdV9wbS5jCj4+IGluZGV4 IGFjY2M5MDguLjgwOGQ3ODggMTAwNjQ0Cj4+IC0tLSBhL2RyaXZlcnMvZ3B1L2RybS9hbWQvYW1k Z3B1L2FtZGdwdV9wbS5jCj4+ICsrKyBiL2RyaXZlcnMvZ3B1L2RybS9hbWQvYW1kZ3B1L2FtZGdw dV9wbS5jCj4+IEBAIC0xOTUsNiArMTk1LDggQEAgc3RhdGljIHNzaXplX3QgYW1kZ3B1X2dldF9w cF9udW1fc3RhdGVzKHN0cnVjdCBkZXZpY2UgKmRldiwKPj4KPj4gICAgICAgICBpZiAoYWRldi0+ cHBfZW5hYmxlZCkKPj4gICAgICAgICAgICAgICAgIGFtZGdwdV9kcG1fZ2V0X3BwX251bV9zdGF0 ZXMoYWRldiwgJmRhdGEpOwo+PiArICAgICAgIGVsc2UKPj4gKyAgICAgICAgICAgICAgIGRhdGEu bnVtcyA9IDA7Cj4+Cj4+ICAgICAgICAgYnVmX2xlbiA9IHNucHJpbnRmKGJ1ZiwgUEFHRV9TSVpF LCAic3RhdGVzOiAlZFxuIiwgZGF0YS5udW1zKTsKPj4gICAgICAgICBmb3IgKGkgPSAwOyBpIDwg ZGF0YS5udW1zOyBpKyspCj4+IC0tCj4+IDIuOS4zCj4+Cj4+IF9fX19fX19fX19fX19fX19fX19f X19fX19fX19fX19fX19fX19fX19fX19fX19fCj4+IGRyaS1kZXZlbCBtYWlsaW5nIGxpc3QKPj4g ZHJpLWRldmVsQGxpc3RzLmZyZWVkZXNrdG9wLm9yZwo+PiBodHRwczovL2xpc3RzLmZyZWVkZXNr dG9wLm9yZy9tYWlsbWFuL2xpc3RpbmZvL2RyaS1kZXZlbAoKX19fX19fX19fX19fX19fX19fX19f X19fX19fX19fX19fX19fX19fX19fX19fX18KZHJpLWRldmVsIG1haWxpbmcgbGlzdApkcmktZGV2 ZWxAbGlzdHMuZnJlZWRlc2t0b3Aub3JnCmh0dHBzOi8vbGlzdHMuZnJlZWRlc2t0b3Aub3JnL21h aWxtYW4vbGlzdGluZm8vZHJpLWRldmVsCg== From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933879AbcJFTEE (ORCPT ); Thu, 6 Oct 2016 15:04:04 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:42359 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933727AbcJFTEB (ORCPT ); Thu, 6 Oct 2016 15:04:01 -0400 Subject: Re: [PATCH] drm/amd/amdgpu: default to zero number of states if not enabled To: Alex Deucher References: <20161006180211.31747-1-colin.king@canonical.com> Cc: Alex Deucher , =?UTF-8?Q?Christian_K=c3=b6nig?= , David Airlie , Eric Huang , Rex Zhu , Jammy Zhou , Tom St Denis , Dan Carpenter , Maling list - DRI developers , LKML From: Colin Ian King Message-ID: <57F6A01D.10907@canonical.com> Date: Thu, 6 Oct 2016 20:03:57 +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 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? > > 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