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Content-Type: text/plain; charset="us-ascii" Content-ID: Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 X-MS-Exchange-Transport-CrossTenantHeadersStamped: AS8PR08MB5991 Original-Authentication-Results: dkim=none (message not signed) header.d=none;dmarc=none action=none header.from=arm.com; X-EOPAttributedMessage: 0 X-MS-Exchange-Transport-CrossTenantHeadersStripped: VE1EUR03FT045.eop-EUR03.prod.protection.outlook.com X-MS-PublicTrafficType: Email X-MS-Office365-Filtering-Correlation-Id-Prvs: f4075bdc-4e45-486e-62b1-08d9bbe411a9 X-Microsoft-Antispam: BCL:0; X-Microsoft-Antispam-Message-Info: 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 X-Forefront-Antispam-Report: CIP:63.35.35.123;CTRY:IE;LANG:en;SCL:1;SRV:;IPV:CAL;SFV:NSPM;H:64aa7808-outbound-1.mta.getcheckrecipient.com;PTR:ec2-63-35-35-123.eu-west-1.compute.amazonaws.com;CAT:NONE;SFS:(4636009)(46966006)(36840700001)(40470700001)(356005)(186003)(83380400001)(6506007)(47076005)(36756003)(316002)(4326008)(81166007)(336012)(6862004)(33656002)(107886003)(54906003)(2906002)(26005)(82310400004)(40460700001)(36860700001)(53546011)(6486002)(70206006)(6512007)(86362001)(2616005)(5660300002)(8936002)(70586007)(508600001)(8676002);DIR:OUT;SFP:1101; X-OriginatorOrg: arm.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 10 Dec 2021 13:51:02.2177 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: cab0d82a-3d8d-482c-af19-08d9bbe41a9d X-MS-Exchange-CrossTenant-Id: f34e5979-57d9-4aaa-ad4d-b122a662184d X-MS-Exchange-CrossTenant-OriginalAttributedTenantConnectingIp: TenantId=f34e5979-57d9-4aaa-ad4d-b122a662184d;Ip=[63.35.35.123];Helo=[64aa7808-outbound-1.mta.getcheckrecipient.com] X-MS-Exchange-CrossTenant-AuthSource: VE1EUR03FT045.eop-EUR03.prod.protection.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: VI1PR08MB4285 Hi Jan > On 10 Dec 2021, at 13:11, Jan Beulich wrote: >=20 > do_memory_op() supplies return value and has "errno" set the usual way. > Don't overwrite "errno" with 1 (aka EPERM on at least Linux). There's > also no reason to overwrite "err". >=20 > Signed-off-by: Jan Beulich Reviewed-by: Bertrand Marquis But if err can really only be 0 or -1, I do wonder if the else forcing err = to 0 could be removed but I must say I have no idea if do_memory_op could return a val= ue >0. Anyway not related to the patch itself. Cheers Bertrand > --- > While the hypervisor side of the hypercall gives the impression of being > able to return positive values as of 637a283f17eb ("PoD: Allow > pod_set_cache_target hypercall to be preempted"), due to the use of > "rc >=3D 0" there, afaict that's not actually the case. IOW "err" can > really only be 0 or -1 here, and hence its setting to zero may also be > worthwhile to drop. > --- > v2: Don't save/restore errno, as DPRINTF() already does so. >=20 > --- a/tools/libs/ctrl/xc_domain.c > +++ b/tools/libs/ctrl/xc_domain.c > @@ -1230,13 +1230,9 @@ static int xc_domain_pod_target(xc_inter > err =3D do_memory_op(xch, op, &pod_target, sizeof(pod_target)); >=20 > if ( err < 0 ) > - { > DPRINTF("Failed %s_pod_target dom %d\n", > (op=3D=3DXENMEM_set_pod_target)?"set":"get", > domid); > - errno =3D -err; > - err =3D -1; > - } > else > err =3D 0; >=20 >=20 >=20