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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?dvqyxZqmCuZn8AOrCkt5jtEHwXeARz7lzvLWu+Br5sOnUsyorWemsgE+BQ6Y?= =?us-ascii?Q?xnT0XIaD4DijhyV/hmAaggEurcd8/Kpe1Qz7TcaFujCe9xj5IQhMdIDQouQ4?= =?us-ascii?Q?22auxy3QfvVZ6RZrwHX23NYmz1TRwCq0eS8uzY3CkBnov3esx7E4km0/dDyn?= =?us-ascii?Q?n435pqaYqJjI8pl6QjdnWvAgHLH+QF8euuOOl3HmX/fLP1+LKPia8/VPjmDz?= =?us-ascii?Q?HuhuEQyxJKwuszLmw+KeswGEjwM9syiZrLCa5CCWTJHU/7SQJ8jDHsnRiA4w?= =?us-ascii?Q?c5e2Vz6rU+S9QoKBzAfXKHtKqOjk+Ec0XT7x+nmqvw4tnF0YqSiRbW6xhFq/?= =?us-ascii?Q?ERiK5mnQs9cyWcxPLSkuLYr05vmwHGSeGTJ6CpL5TKTXsGPh5b99v6k33Qp8?= =?us-ascii?Q?eQzXXL1z4eFnVeTglLlEDk9pMoX3IRsQU+NskM7b1ZzzFO7XbKQgjwgo7uwx?= =?us-ascii?Q?lHLa5FfACnSaEzlRlkaR1IWOIMgyAIQHjc6M1sPWdXk8fkXlneGzEph7oJe2?= =?us-ascii?Q?Ug7cVkkONJ/aGKYT49QFYv9Oxsb4SgO6CcmrJ8d1Ng1E92Npvnr/bzbnbmMh?= =?us-ascii?Q?mL2ditXuGfniL2HzaAixbSEDFnAjswadvRBtzHkLoaK3dtoMB3HUC6+G4Wfr?= =?us-ascii?Q?sZ9h1oxISODqFz9GwP4Fjeq/Voci7Vrd0FMYOvgDsifin2+FdultSbx2mZd+?= =?us-ascii?Q?eqQv869643wGKKXrq0g2XUXWFs99645AUaZVsfZYcqOIwNeZxtqR1IzFbVrO?= =?us-ascii?Q?HKV2GM+OXRWu7M7HRtnltElb7nRhyFoRsbuHtNj/2kVWnMOrehvxsUgw0fUM?= =?us-ascii?Q?vQz66J1Spf8YruragLOkXfIe7jnPNsdyYCzK8KDFE7yFpug2l+bfN1EfHret?= =?us-ascii?Q?y3dshskahU6cRqNxrapqQDrxHFpoaMNnngG8kKe1JT6qJMrhwidyVwsxht6F?= =?us-ascii?Q?/3/GtV9N2aRa13dHsV3/Iw0AoG58KQu6Z2HI8s4ojeAld0tTlcnqNO5OoK3a?= =?us-ascii?Q?CmjTKV8OR0scxXAmkOHrQZ0WtaEn7oBrWasa1RqbL0rtfZAM6BS8kS9SzG+b?= =?us-ascii?Q?aCwaSEQwstzbqCLgMzQwFmI0/oKTUj0pkz/fESPOTHepEalbC/4FoYGgeqJS?= =?us-ascii?Q?ThVHXyfGAGKPUdNSMUreFsr07Hm9SR14KsU3soPnmpHjFyl0ui/4Is/LbIkl?= =?us-ascii?Q?EsmGSozN2gfeEdSDNQzd4Ui4NJ3MiHqGMlODMNzZM5EcPbg0FnAjlvYfdaFa?= =?us-ascii?Q?B/hkIm7+ea9RnRCw06dFLvcQ1uWrDGKlD4Mi5BC7atCLDEP54QkGAeMeS749?= =?us-ascii?Q?EJy5COZuN+6HSaH2rr9DbWdfouro3hufCFNJhOen9z4GYhJ2D7TFONv1Zwti?= =?us-ascii?Q?FXQai5gRwD6T8JQaMxSrH3UWTZ6pZVOmBPrSLyvxAC0ROyg99S/MYNGmh/i1?= =?us-ascii?Q?HVWuU+MtLcN0xKYH5/ZXtyobpwqPs/u/Dm3W8uDEbXVoUYtODnrtiHbyDTg1?= =?us-ascii?Q?vYQ99TDIheJodj1NSUz+P+ezSeeB7iXblWYbLFrC+tHAQ3qXts3OGpdRFPjd?= =?us-ascii?Q?jjJwzyy4r+srm5ecvJ4mx4NnyQt8J8jzyIweCoc5?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 150508e1-da3b-4337-5f22-08dd5b223c57 X-MS-Exchange-CrossTenant-AuthSource: CH3PR12MB8659.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 04 Mar 2025 13:41:15.7851 (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: kHzKiBV1k9wvQW6pL0pRp8fDmJoHpQJ881zmEG9jYaCwLhw9Sn04SzSApRWTd39c X-MS-Exchange-Transport-CrossTenantHeadersStamped: SN7PR12MB7203 On Thu, Feb 27, 2025 at 12:07:29PM -0800, Nicolin Chen wrote: > Reported by smatch: > drivers/iommu/iommufd/device.c:1392 iommufd_access_rw() error: uninitialized symbol 'rc'. > > Fixes: 8d40205f6093 ("iommufd: Add kAPI toward external drivers for kernel access") > Cc: stable@vger.kernel.org > Reported-by: kernel test robot > Reported-by: Dan Carpenter > Closes: https://lore.kernel.org/r/202502271339.a2nWr9UA-lkp@intel.com/ > [nicolinc: can't find an original report but only in "old smatch warnings"] > Signed-off-by: Nicolin Chen > --- > drivers/iommu/iommufd/device.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/iommu/iommufd/device.c b/drivers/iommu/iommufd/device.c > index 6dccbf7217f5..b812ae40f382 100644 > --- a/drivers/iommu/iommufd/device.c > +++ b/drivers/iommu/iommufd/device.c > @@ -1348,7 +1348,7 @@ int iommufd_access_rw(struct iommufd_access *access, unsigned long iova, > struct io_pagetable *iopt; > struct iopt_area *area; > unsigned long last_iova; > - int rc; > + int rc = 0; This is a smatch error but it can't actually happen because: if (!length) return -EINVAL; And: if (!iopt_area_contig_done(&iter)) rc = -ENOENT; Prevents an empty loop for iopt_for_each_contig_area() And each loop does: rc = iopt_pages_rw_access( Which will zero rc. If for some reason rc was used uninitialized then it would be an error so it should be rc = -EINVAL. I fixed it up. Jason