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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?zBSAz/vWCIvmSWwwMk+q3bIQZPUWccBfBe9YmEIndLqrQIXwqqG+ApCyWeJJ?= =?us-ascii?Q?BGVSAs1BN2SaylCsU1Lw3kGyaOqSNfBp1V+kf/7+zq3VFiP82wkM1E8Jp73i?= =?us-ascii?Q?Kr4Djc/ZB+KbQ+dLAockCGUjhy8VbWdYJOqTIZ6pWF60p8xz19ykz2YkCMLE?= =?us-ascii?Q?XfvH8XYh7etfa5o4bU/8GpIGcKYhOXFJgfMTlD5R18KSaOsGcCoSRKQ1ivjJ?= =?us-ascii?Q?+RbZJpNsoW/e3m98Xa+1cKyMHnGm32AOjCDUjEKwskyvyj3dMhg/M7LjFbkY?= =?us-ascii?Q?CFUPuRDf/7WAQTUK7vtP2hCrZdXw7dkp2uiecsMhXqn8N1Kg++AbzIZqCEI3?= =?us-ascii?Q?5qWgOfWfDrT0Itu+YXhd+NOuru2UiXDa1aNlIXI+wjdcS8NyLbyAIUzMvs+G?= =?us-ascii?Q?o2WUR884/eYftVBh/arXoHhsb1KUuuLs1VKHBzMwB4FVne1m61a/jDWLGTja?= =?us-ascii?Q?KhVn6tBMp2CUhg6wQbAWjy3m+5XX1qBk0GchPtxIdi3Fwm8qp8XSOLko5QGz?= =?us-ascii?Q?zZp6BSkmCaPw+RTputqkMC9BVx21J/TIhbavTKnhqbZQCNb9OT/jL41HinJX?= =?us-ascii?Q?aWY9mzokrBjPjyBRKRP4jbBTjYCHPJ8Mq8FiyU5k5GS7qEFu6VO8OtwoDa2j?= =?us-ascii?Q?iPzv8ApA0IzrSENmGSIfAk05zdp+RoSxibC46QZwIVa6zSvUlMhiBkpp+MTN?= =?us-ascii?Q?wgaLd4IWosYkBboBYQMc9FJ41S6sg/xFTcR03MSQwwPI6A089bxoRDbdBGEc?= =?us-ascii?Q?jqmecEiU6U714H9uyoCJWP6pKRhq70pL6WtVtUqUAseRiuQ1RCa4YsujHRTO?= =?us-ascii?Q?f6i2OMpcaF3kcZAXXCmf9hoC/PGpWxcqUEKE56EC6eAze9dRWCUm41i/dGFx?= =?us-ascii?Q?QTeROdAO0Dtix3Krz+LEediN6sYPnwi2C3fWhaHIlsDdw4dpvzjdeF36KGnd?= =?us-ascii?Q?ZgliWWjjQhsKFvT2JhlcELkgumJSkNPz5m++imCuJUUmBzYq/3uwAA68Ixyg?= =?us-ascii?Q?F3GkE0F3jJdr81cwrvmPfyzdA79bHBr55vPR2PfrcL6qu36G6FDkGs63M0pV?= =?us-ascii?Q?R9XQV1sg5FzQkLu7d8lHb7dOAoSf67xB853oWYRKrAx8zY/QbdBwWHVAM9Xg?= =?us-ascii?Q?lTM3fUewPJn8UlsOxSnxoCDwRo0SQ+xZ3jUMpxVgZ659Enoen4IHVUjW4Svk?= =?us-ascii?Q?hyc4l+BumY7ZVyRzjdQQpweTwifqyq9Lc7eEsSvR39InWYHUSP6Ho/RASeHQ?= =?us-ascii?Q?FyM9XAfaU2lrBzw4A4KDtRTuYLuvxCV/7Q0lOVhHqg+BpdoG4gUgw2Q6RXMf?= =?us-ascii?Q?jKqAKQLnJrPuohdncL3y+y/mYXRSjO/1S9ypVl80shdOPn6mDIhOtOtqqPJ3?= =?us-ascii?Q?5H1069pOCHBonPZRgJ62pVLTfj+pa5dU7BMlU/5U16ZChK3HHRZv86E7h4KH?= =?us-ascii?Q?oMwH1i5dl7ABWmMe5EUSRr44lAjFhX1n/2YSleJskMCCeRi8LTdajKO55O8R?= =?us-ascii?Q?JDEM9QUnCPBpWHURnxO/l8F2zZ+9cgT0fTVYvZ7qCdrW+s9jPG6bxPTjnQZR?= =?us-ascii?Q?qFOLunsVKu7gNsUBIjREQsPIet3l9UP73JGtmfkEWla4QOy+5VjBIzj2NqTZ?= =?us-ascii?Q?vg=3D=3D?= X-MS-Exchange-CrossTenant-Network-Message-Id: dd2b4017-83eb-45e6-9d24-08dddc2dd3eb X-MS-Exchange-CrossTenant-AuthSource: DS4PPF0BAC23327.namprd11.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 15 Aug 2025 18:59:14.6633 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 46c98d88-e344-4ed4-8496-4ed7712e255d X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: PJQ/MyaVAwkZWIw6UOavBFpnAtedQV6Ds1royM351//SmSsyv+QQAP245L/NqEeCD72utEtOnNVqRhfxkYHlYm037I+YSm1/CAAaftKgg3w= X-MS-Exchange-Transport-CrossTenantHeadersStamped: DM3PPF195D11F0C X-OriginatorOrg: intel.com On Sun, Aug 10, 2025 at 11:47:42PM +0530, Akhilesh Patil wrote: > Use kvfree() to free memory allocated by kvzalloc() instead of kfree(). > Avoid potential memory management issue by matching alloc/free routines. > > Fixes: 52929c2142041 ("fwctl/mlx5: Support for communicating with mlx5 fw") > Signed-off-by: Akhilesh Patil Hi Akhilesh, How about making the commit message more specific about why this patch is critical even when no immediate symptoms are observed. Based on the current description, a developer might think "this works fine in my testing, so it's not urgent." This type bug is particularly dangerous because it can pass code review and testing, then cause mysterious production failures that are extremely difficult to trace back to the root cause. If this sounds like I'm going overboard on an obvious fix, I am doing so intentionally. I am encouraging you, as a new contributor, to show that you looked into how kvzalloc() works. I believe it can use either kmalloc() or vmalloc(). You don't need to be a memory alloc expert to submit this fix, but demonstrate that you looked beyond a report in a static analysis tool. Also, that's where the interesting learnings appear. Similar to what Markus mentioned, a simple message stating how this was found is useful too. --Alison > --- > drivers/fwctl/mlx5/main.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/fwctl/mlx5/main.c b/drivers/fwctl/mlx5/main.c > index f93aa0cecdb9..4b379f695eb7 100644 > --- a/drivers/fwctl/mlx5/main.c > +++ b/drivers/fwctl/mlx5/main.c > @@ -345,7 +345,7 @@ static void *mlx5ctl_fw_rpc(struct fwctl_uctx *uctx, enum fwctl_rpc_scope scope, > */ > if (ret && ret != -EREMOTEIO) { > if (rpc_out != rpc_in) > - kfree(rpc_out); > + kvfree(rpc_out); > return ERR_PTR(ret); > } > return rpc_out; > -- > 2.34.1 >