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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?I1ksOA23ZlurvrEB94rTCtEXT09y30bvUy+2hQU9C+PPBdjvE56mxSfIDthJ?= =?us-ascii?Q?xNBNFRqDSGYUPB8myKzdJeeaxulcfSHDJq5AmDt7Q4tTxewYvmOEY+Vbvc73?= =?us-ascii?Q?pzcvgrBpbf6DzDdn+HuA7hmFE1s8FGXRSoTzpxFNItuII2rHDri/vN2ZsA6W?= =?us-ascii?Q?sIeBQX7RKENJ2Eae6CIueEExEKId0KZuqidiMO4jTtWCRJWFVo4htuZGrM89?= =?us-ascii?Q?E3WN7/gV3ObfVks9FqUHulyxbIXsvBPJjS699REiW2Lz8me2yKQVdNQ4mo+B?= =?us-ascii?Q?6o04PtoLbG0XgvS5p6C51kCYD9R1+QtmXWF/y/JZcLWl8LARY53wKsSLIGuK?= =?us-ascii?Q?ot0R16eZf3ByDa+gS/G39u8w/cbRxTxnO9so3JYGP3Jr4YtgYbP3ttpWR614?= =?us-ascii?Q?b2GJYBJoRuB0f9Gmj91tQmOi6kqd1QrG7fNAsvzGfSgrz7cHCcTmJ5i9JtlO?= =?us-ascii?Q?0IrQXMTPfOdmSdnJL6IomZRKKUUAGWSWRgU4JWIAYxYpMIpjbj5ccmjNTkb7?= =?us-ascii?Q?45e7HbNTEKFw6LHTnBceh8Iof+DoJ57/nQAHYKNR6GstE53CNgomZrySgP9N?= =?us-ascii?Q?dcl5lrUtmy+uXnWw9stlUptKWG6sACRpw8PO2LtDf/MeIdYkyKWtlOGLTefZ?= =?us-ascii?Q?XRh4mtGfRc827tHSKXmU5/j9jOQ+SpmX1XKE2FPtSFKQrTprNZbcEq6ca5Xy?= =?us-ascii?Q?CT5mx9mqYtZTBWEMc97/ZGSGyaKDLx0cqZgzo3Y/T1SdZnjCN3BqaeyiT6bw?= =?us-ascii?Q?MTWfbgMwBmQpuizJdBFoDDVOJ24Z4hfLtuNl+FySKSGa9DokIzQcAFPKbdwo?= =?us-ascii?Q?iO09rS89rSrqzn/4jEvDPDCud1ndrJvHXzB+xFNh1sthQE7/Z5t+FeYx5kxb?= =?us-ascii?Q?Yv8Cy7tk+vVQhOU4J9fnR4+6VE1hZNRgOlfBPahiyHcnc2NPmOpjcItN2oZw?= =?us-ascii?Q?H3LtxAiAUUsy2y8xKl/ROMJvvDPok9miJZu3FkvOaFZTWIT9/+8MF9zcj8D8?= =?us-ascii?Q?Awv2XnDxySrUEda+gzQqONtJv10cCTAw+NiEEVK2RBINooQH6W1ITuk4zQLE?= =?us-ascii?Q?4yg3KCFWPY2hMG/B9DxQQvrkAuIhoWqaIRqn4rtcYTHi2nrukvG+eNPuKGq1?= =?us-ascii?Q?PRC91BUiXXm1X12c/nx3530FEBmLNMKzr/YCBhfTvExRCx6WAqqes0J7PHKn?= =?us-ascii?Q?/Hvt3Yfwns3pPQXxeSZPNmhD6si7PWjbPF9TXWJDsoYmFBFThL/joQe9F3LS?= =?us-ascii?Q?9zJwTMakY8B4tF9mU47V9glgwpVAzdOWFJeUYfzVGYAKxE63LHoMVSV7buQ6?= =?us-ascii?Q?q32XDoRPbJMAXsBMB0PxFRCJoiMuKlyg56OMSL5L0xKZzmd5QRaoW+uCtE4d?= =?us-ascii?Q?hB0SJi8lhgrr+7IshWwL2aeaAmUAq58AB3ELnBeC3jNQma8MLboh9ceUXXRA?= =?us-ascii?Q?hf+bEljCb3Ylpj4+KrR3emCbX8UbGjKlf35uL95vRY1amm5w3fhywt8ONqsR?= =?us-ascii?Q?sLMVLAOuxZSInU0AxRAlq9drWxUqVzMvrc3LhVITxfGWLMysmXzza7j2AItY?= =?us-ascii?Q?+xaCWsiXyH+wWG6ZBoF5TkCiE3bQzuCpeXd5T9mC?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: d735e322-411d-457d-199b-08dd713b28a1 X-MS-Exchange-CrossTenant-AuthSource: CH3PR12MB8659.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 01 Apr 2025 16:35:05.7871 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 43083d15-7273-40c1-b7db-39efd9ccc17a X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: DvVGs69yEx7wvuHu0oVnkAGMa2RNoxlSMxRUMY/18a0xOIiRQy85nlbk4Pt//jKJ X-MS-Exchange-Transport-CrossTenantHeadersStamped: SJ2PR12MB7867 On Mon, Mar 31, 2025 at 10:04:05PM +0300, Leon Romanovsky wrote: > > > On Mon, Mar 31, 2025, at 20:45, Jason Gunthorpe wrote: > > On Wed, Mar 26, 2025 at 12:58:54PM +0200, Leon Romanovsky wrote: > >> On Wed, Mar 19, 2025 at 02:23:49PM -0300, Jason Gunthorpe wrote: > >> > On Wed, Mar 19, 2025 at 02:42:21PM +0200, Leon Romanovsky wrote: > >> > > From: Shay Drory > >> > > > >> > > syzkaller triggered an oversized kvmalloc() warning. > >> > > Silence it by adding __GFP_NOWARN. > >> > > >> > I don't think GFP_NOWARN is the right thing.. > >> > > >> > We've hit this before and I think we ended up adding a size limit > >> > check prior to the kvmalloc to prevent the overflow triggered warning. > >> > >> The size check was needed before this commit was merged: > >> 0708a0afe291 ("mm: Consider __GFP_NOWARN flag for oversized kvmalloc() calls") > >> > >> From that point, the correct solution is simply provide __GFP_NOWARN flag. > > > > I'm not sure, NOWARN removes all warnings, even normal OOM warnings > > from regually sized allocations which we don't want to remove. > > I disagree, this allocation is called from user space. We can safely > skip OOM messages and error here will be enough. That is not the standard, we OOM splat on all userspace allocations too. GFP_NOWARN is supposed to be used in cases where the OOM has a recovery and nothing will fail. I think the right thing here is to limit the size, though I'm not really sure what the limit should be. Jason