Received-SPF: pass (google.com: domain of linux-kernel+bounces-127858-linux.lists.archive=gmail.com@vger.kernel.org designates 147.75.199.223 as permitted sender) client-ip=147.75.199.223;
Message-ID: <6a6ebf5a-da64-4c5b-b819-cbcbb097fb55@oracle.com>
Date: Tue, 2 Apr 2024 16:53:53 +0530
User-Agent: Mozilla Thunderbird
Subject: Re: [PATCH] drm/panthor: Fix IS_ERR() vs NULL bug in
 group_process_tiler_oom()
To: Boris Brezillon <boris.brezillon@collabora.com>,
        Steven Price <steven.price@arm.com>, Liviu Dudau <liviu.dudau@arm.com>,
        Maarten Lankhorst <maarten.lankhorst@linux.intel.com>,
        Maxime Ripard <mripard@kernel.org>,
        Thomas Zimmermann <tzimmermann@suse.de>,
        David Airlie <airlied@gmail.com>, Daniel Vetter <daniel@ffwll.ch>,
        Heiko Stuebner <heiko@sntech.de>, dri-devel@lists.freedesktop.org,
        linux-kernel@vger.kernel.org
Cc: dan.carpenter@linaro.org, kernel-janitors@vger.kernel.org,
        error27@gmail.com
References: <20240402111740.1700310-1-harshit.m.mogalapalli@oracle.com>
Content-Language: en-US
From: Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com>
In-Reply-To: <20240402111740.1700310-1-harshit.m.mogalapalli@oracle.com>
Content-Type: text/plain; charset=UTF-8; format=flowed
Content-Transfer-Encoding: 7bit
Precedence: bulk
MIME-Version: 1.0
X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1
X-MS-Exchange-AntiSpam-MessageData-0: 
	=?utf-8?B?Rm51MlNBSHRKSDcyTzlEem9ic0xBcjI0OWFGTERZMGRXeVpnL1ZlVk1EMnR6?=
 =?utf-8?B?VEJtZTRVSUNuTDJDT0RLcEp5TjBKdFZKSFhqNWZGOVNUdXBhc0xlSzhlTmpt?=
 =?utf-8?B?c0F4aFFkWjJGUXhoYUpGNktMZDFOQWREWFROWDl5SXoyYm9OMnI4SDRCMlk1?=
 =?utf-8?B?Si8xdmFPZE1KemhYd2VVOHZIUExSNDBCUHYrTnhZOVI4TGxHaHA2Nm1jd1M5?=
 =?utf-8?B?dnVsbXZqa2ptWkQzMVpXSEU1azVOYks1YzBxUVpDQmVIZU5EMDJKMytCNHps?=
 =?utf-8?B?dGhmejhnSWtSOTJFZzBQNWxZaXlEd2lkMmlnZVBoYlp2UkpsdXpINGJWSWZM?=
 =?utf-8?B?UkN0UGkwUUxwbk1KaXRVTlJqU2RUN2dPZmJ3dDUyVWM3QStPb2lFZURnTGs3?=
 =?utf-8?B?TktQRWJSTGpNejJ2M3lka1RQYVV6YkdkZDdLWmk2UXp3KzFWSXdTZ0JHT29N?=
 =?utf-8?B?dm92Ulg0cmFoNXQzMU5VNlZuTWdPaG9jczZDTFUxaS85dGI5OUh6OGpkLytk?=
 =?utf-8?B?ci9VSEdFZXQxWnVzM0QvTmkwTmx1d2ZhZFN2NCs3WVVFY29yUGF6VDV3bGls?=
 =?utf-8?B?MWJ5YUF2bENsSU11aVFyc2t2S3ljakJqNFFOQW9aMFZkOFV5UmRHZ0tuK1JM?=
 =?utf-8?B?Zll6aDR3b0hhU3p2cFhPUkdnQVBVbEVIdGp6OTRGdXhRdzBCcFpONVZRODB0?=
 =?utf-8?B?TXY5a0tnQzNpbkczbmZiOGRCOGkybnJSVU9VMVlpdkY1R05QWXN5WXRPeHpR?=
 =?utf-8?B?S0pFeXZFQTZhbUVQM2FsVXlyQ3NNbVV3aUwwUFdDMm5oZEtVTHhnd1RhWklC?=
 =?utf-8?B?QWV0WmpMSnBSY3NzWE5HWUxKZXVxU215VVJWbERaclFpZHJEZm5QQW1nU1ly?=
 =?utf-8?B?OHJnWDhNeklWMjAzRllLUWxHV2xnb2Y2RHhLU3FZbnJQQzNUY1o1Zi9sQytP?=
 =?utf-8?B?MnU4cThXYTJFcmM1bllwWXZVcm84WjlOYnJHek1BMXlyM1IycGVFMURyd2g2?=
 =?utf-8?B?NVV5U285bFcrM2lqdzNQN0k5d2ZRZXB5T0xlS2tHVFY3OFBkOEpuS1FXeWs2?=
 =?utf-8?B?bTdvVXBDcEplU1d2UDlqV2ZzWTRxV2JNclVrd3FtbVJEUVh3b3RqNGZrZUI3?=
 =?utf-8?B?NGdMUUh2QXRYSWt4bkthaDhWMTY0OFRubCt2MjZFZ2dUWkdzRS9oMWJnUDRB?=
 =?utf-8?B?QUlMamZKeExmR2pLMUJPVDYrTkV4ZTBhVHJBa1U3djdUcytsd29qRklJN05N?=
 =?utf-8?B?RWZRUGY1NnVyNUZsTnowVHFqR1d2OFNJbFFzbitlc25pRUlnaWtkWlFWUEVk?=
 =?utf-8?B?WGJYeUowem9EQVMvL3NLK3g1em41cmZuRXJCY3dXRUJsQmxpNnNmUHcrb0lm?=
 =?utf-8?B?QldKeSt5R1Nabkx1M0Jna1BJNnNBM2Z1K2kvbCszVVhvWit5VHVnaXNya2Ew?=
 =?utf-8?B?SFd0VDRtZm9wZ2d2d0tERWR4Skw5WHZ1aWdOR1REcVV4Y3U5M0ZoQzdWdnhD?=
 =?utf-8?B?QWNjSE1DeGplRkcvd1BiT3BoTGRXTHJ0dGZCWjVKcUcyeldONEg2aTBkTWR3?=
 =?utf-8?B?WmVKZFVDT0VnVlNXSVdpVmpaRTZsTE5HRE5IcTEwMHg4dzFUK2ZkSTVhT0dt?=
 =?utf-8?B?RnBzZ3F5Z0wzdkE1c0xXOTZub2U1ejlKYVhSRGJwWThIeUdCbzgveHcxWW45?=
 =?utf-8?B?a09FVVFRdDBlNjlTYmUxc1hyVlJZYzYvbUJOVmxwUUJERGVhN0xzWWFGNU95?=
 =?utf-8?B?alhIbi9iYmFBWkd2d2o3TmVxM3phcitJM1orc0lXWFZNcytwQXcvdHhBVE8x?=
 =?utf-8?B?am43Zm1FanRtQXZIMDVaNE8ycjA2aVV0YU9BSXhBOFh4dmN5L0JFbkh0NzRt?=
 =?utf-8?B?U2xna1dvMjlBdjkxK29WTGtINnZRVm4wcGxvZGhnWC9PdHJ4K3d6TlZmaEJo?=
 =?utf-8?B?L2x4QXdqRmpZUXhtN3pXb3pmVHFsVFQvTVByMC9UNS9Ld2RTeGtHUTBGSk1B?=
 =?utf-8?B?aVlJU252cksrSGVvSVBCNExVSWptQzNxbnNZcml2RERCckxZYmN0SjlKaG1E?=
 =?utf-8?B?QmZ6di85ZGxSQjRTMXBnaFpNTVc4UjZsVnhuOUFuN2JpVWFpYmtFemF5Sm1K?=
 =?utf-8?B?K1ZuS2hPcit0M1F0a0FSMnFjR0hpQmJlMHliUkhkZnhVemtVVjNQN054TnVj?=
 =?utf-8?Q?TMkz+2Uv7IdZ0xGX8WtxJmk=3D?=
X-MS-Exchange-AntiSpam-ExternalHop-MessageData-ChunkCount: 1
X-MS-Exchange-AntiSpam-ExternalHop-MessageData-0: 
	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
X-OriginatorOrg: oracle.com
X-MS-Exchange-CrossTenant-Network-Message-Id: ac2358fe-0bc6-40b1-b055-08dc53076613
X-MS-Exchange-CrossTenant-AuthSource: PH8PR10MB6290.namprd10.prod.outlook.com
X-MS-Exchange-CrossTenant-AuthAs: Internal
X-MS-Exchange-CrossTenant-OriginalArrivalTime: 02 Apr 2024 11:24:02.4259
 (UTC)
X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted
X-MS-Exchange-CrossTenant-Id: 4e2c6054-71cb-48f1-bd6c-3a9705aca71b
X-MS-Exchange-CrossTenant-MailboxType: HOSTED
X-MS-Exchange-CrossTenant-UserPrincipalName: 9AkiFPeQ84NzL3OvCoYlj3snUZ64NvPqY1483hcVnefMbRfrkqjJCGU9GaLbvLfU5Z/yDpakNZSQriiZ6Bb7VxUb/CExWazf+cQA6JV9evMVoNtHUsWue+9SjcYwwNvf
X-MS-Exchange-Transport-CrossTenantHeadersStamped: PH7PR10MB6311
X-Proofpoint-Virus-Version: vendor=baseguard
 engine=ICAP:2.0.272,Aquarius:18.0.1011,Hydra:6.0.619,FMLib:17.11.176.26
 definitions=2024-04-02_05,2024-04-01_01,2023-05-22_02
X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 malwarescore=0 suspectscore=0
 phishscore=0 bulkscore=0 spamscore=0 adultscore=0 mlxlogscore=999
 mlxscore=0 classifier=spam adjust=0 reason=mlx scancount=1
 engine=8.12.0-2403210000 definitions=main-2404020083
X-Proofpoint-GUID: 8tj3uaY8VTqC0HVYnzhsaiJQRkLFRmd2
X-Proofpoint-ORIG-GUID: 8tj3uaY8VTqC0HVYnzhsaiJQRkLFRmd2

Hi,

On 02/04/24 16:47, Harshit Mogalapalli wrote:
> panthor_vm_get_heap_pool() returns ERR_PTR on failure, update the check
> accordingly.
> 
> Fixes: de8548813824 ("drm/panthor: Add the scheduler logical block")
> Signed-off-by: Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com>
> ---
> This is based on static analysis with smatch, only compile tested.
> ---
>   drivers/gpu/drm/panthor/panthor_sched.c | 5 ++++-
>   1 file changed, 4 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/panthor/panthor_sched.c b/drivers/gpu/drm/panthor/panthor_sched.c
> index 5f7803b6fc48..d34f213795a3 100644
> --- a/drivers/gpu/drm/panthor/panthor_sched.c
> +++ b/drivers/gpu/drm/panthor/panthor_sched.c
> @@ -1343,7 +1343,10 @@ static int group_process_tiler_oom(struct panthor_group *group, u32 cs_id)
>   	if (unlikely(csg_id < 0))
>   		return 0;
>   
> -	if (!heaps || frag_end > vt_end || vt_end >= vt_start) {
> +	if (IS_ERR(heaps))
> +		return PTR_ERR(heaps);
> +

Please ignore this patch, doesn't look correct on looking at more closely.

I should have just done this:

diff --git a/drivers/gpu/drm/panthor/panthor_sched.c 
b/drivers/gpu/drm/panthor/panthor_sched.c
index 5f7803b6fc48..617df2b980d0 100644
--- a/drivers/gpu/drm/panthor/panthor_sched.c
+++ b/drivers/gpu/drm/panthor/panthor_sched.c
@@ -1343,7 +1343,7 @@ static int group_process_tiler_oom(struct 
panthor_group *group, u32 cs_id)
         if (unlikely(csg_id < 0))
                 return 0;

-       if (!heaps || frag_end > vt_end || vt_end >= vt_start) {
+       if (IS_ERR(heaps) || frag_end > vt_end || vt_end >= vt_start) {
                 ret = -EINVAL;
         } else {
                 /* We do the allocation without holding the scheduler 
lock to avoid


Thanks,
Harshit


> +	if (frag_end > vt_end || vt_end >= vt_start) {
>   		ret = -EINVAL;
>   	} else {
>   		/* We do the allocation without holding the scheduler lock to avoid