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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?utf-8?B?dEVuZ2NDWmtROFZ3Q3hiSVhtbHVtY0x4ZEVsd294d1Rld2dNMC9Tem1TNGo2?= =?utf-8?B?SjNmL1F2QWVRVVVvK1czOEFMem9CRTc2ZUZ5R3ZDdU5CLzhJRkpzYVpIdjNH?= =?utf-8?B?L2RWZ2tXcmRiUG5IZ0doTnZtVjNMSEVyTGlwZXRyZDBYREN5Q2tuNW05SjdL?= =?utf-8?B?R0N0anFyQklick5MQ0NrRVh4dWJ3SWR2RkM2aWsxaGlPUlpkYUFPaGhqSlVP?= =?utf-8?B?WVUyY21mVlF0NzNCSGxjamVnd0dyZFk4dm41Rzl0Tk9HYW9nUUNFWHdLT2VD?= =?utf-8?B?bkxTMUJpeEJ3MkZXL09nbzBxcyt2Ti9BaHpWSkMrc3l6YlFYalA4Z2cxcE1W?= =?utf-8?B?OHMxSk5UY0J2VmRCaEIvNnpFZHlXODF3YVlucDZpVWpLSmxpSUpaNG1EaHNw?= =?utf-8?B?anRJUGlHcCtVa2UrVUprQ1NuUVJhaFNkV0FEbmw5WkthRUdYRmZXMzNDZld3?= =?utf-8?B?S2lqaVVjQ0cyTjJxUGVMYkFZc1laNFo5QmthbFJFeDhrc0NwOGVwRHNNRmI4?= =?utf-8?B?RElyZDVMa1JhSlltQlB2T05JV0ttSmRjOUcyQkZUL01YU0kyaWdtQkNKOHc3?= =?utf-8?B?bUtpeFZZaDVIenZEblAxRDhJQlptd1V0YU9LTkg1dE9QTHZQSUJ1MVgrb2x3?= =?utf-8?B?NU5aV0pBM0FHdlF6TStpaHBEWExVV1hXa0VDdGkxRnFCZ0FLb0Z3ejZOLytq?= =?utf-8?B?ZjdWZTFiYzhxY0dRVGo1VUVuR2xOQjJsbW9zbDEyUUNSZ29LT2FZL1FBTzlE?= =?utf-8?B?dzVkTy96K1diMmZFRVhieDVzaDhqTTBZZWxoSW9SMDhnVnY1UkkreGN1cHRq?= =?utf-8?B?T3NUYUpMcmZpb0tSZDFKd0h3UlRoSlo1eGdYd0FVaUpIOUMySDBYRm9UTVZB?= =?utf-8?B?WTFDRllPV2Z0NW1HVHZBNXlRUjhXUUJ3MmV3U3Avb3QwcmVNVWlmMmhrSTQz?= =?utf-8?B?YTZ5cnkvZW83Z2lNMmNKVXRzb0w5U0pFZnQxbnZqd1A1bjE0eGlhdUZ3VTRU?= =?utf-8?B?U2xUTGpIYjVvcGxnd2JYOHp3Z3VHYUVHV3h6bVRZY2l1K0czNW0vZUw2a0xY?= =?utf-8?B?Ukx5WmowbGZjeXFiNktwMU5La1hmeWZXb0tMMFpORU5JRkVKRkt2SWlaVUxJ?= =?utf-8?B?UVhEYVJLTlkyVWY4SlhsSzNCSFMrL3drNHlCb3dCZmx2RUpuWWJYMVBVY0Er?= =?utf-8?B?aXVBOHNSU0w1VWF2alZrRDlmRlV1Q0pGQnZ0bFZUbjQxOXlyNXFSdVRVRDFx?= =?utf-8?B?K3JsREoxTkRhZjBtMEpRYlhpZk1MaXN3Wmdsb1pSMFZMOHZHeTBma1pieTBz?= =?utf-8?B?WHcyWlBHR2FmSXhTR0xSMDQyckpha2YvanRMSHU4djU2N09qR0tVZnNmMjBG?= =?utf-8?B?bVczQmdacGFzcVh5RE9sNHZEMHBDNjZUQnhVNjYwR0R5VlZtMi9mOGFsTHJ0?= =?utf-8?B?ajVsVW1jYkI0czFTNWszckpvUDYzcC9WK1hRdE0zMTNUT1R1UXJOZC9lYkFE?= =?utf-8?B?UWJWbFl0MEsrM3dpMWtiaXB5b3dadTR0Z1Bna01tdGFNUGlLc3Y1ZG1jVHZV?= =?utf-8?B?R0gwS01SNk5JaHFKTlFCeFlNajN5QVp2Y05oWEpxVzJoU0tGNHRXbnU1aGNF?= =?utf-8?B?YjJBVDZoZVVXUi9ycHBEeVk5ZEVWYWxFN2hNM01ZVlE3WE1WS05IaEtJMU02?= =?utf-8?B?dUJNQ3lOalVtRzhDcEJlcWtHY1hCdVp3STVqOUIyZ05xY1BmR1ZLWllkOC8x?= =?utf-8?Q?0yITrBQ26sHhqyH/k00XOHsOm9BNWvrF9N4pfbV?= X-OriginatorOrg: suse.com X-MS-Exchange-CrossTenant-Network-Message-Id: 3efd04ac-4729-4db5-35ab-08d93d6c1df4 X-MS-Exchange-CrossTenant-AuthSource: VI1PR04MB5600.eurprd04.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 02 Jul 2021 15:14:41.8591 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: f7a17af6-1c5c-4a36-aa8b-f5be247aa4ba X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: F0W+yx/I2k52wG8mkb1oTpD3crdx+gNkEC4aD3HsvXmVAIHIykMK+YS9FSpTalg2anvuXf39Amv4cwnDkFuKpQ== X-MS-Exchange-Transport-CrossTenantHeadersStamped: VI1PR04MB7040 On 02.07.2021 17:12, Jan Beulich wrote: > On 02.07.2021 16:46, Anthony PERARD wrote: >> On Fri, Jul 02, 2021 at 02:29:31PM +0200, Jan Beulich wrote: >>> On 01.07.2021 11:36, Anthony PERARD wrote: >>>> On Mon, Jun 28, 2021 at 01:47:03PM +0200, Jan Beulich wrote: >>>>> --- a/tools/libs/light/libxl_x86.c >>>>> +++ b/tools/libs/light/libxl_x86.c >>>>> @@ -531,8 +531,18 @@ int libxl__arch_domain_create(libxl__gc >>>>> if (d_config->b_info.type != LIBXL_DOMAIN_TYPE_PV) { >>>>> unsigned long shadow = DIV_ROUNDUP(d_config->b_info.shadow_memkb, >>>>> 1024); >>>>> - xc_shadow_control(ctx->xch, domid, XEN_DOMCTL_SHADOW_OP_SET_ALLOCATION, >>>>> - NULL, 0, &shadow, 0, NULL); >>>>> + int rc = xc_shadow_control(ctx->xch, domid, >>>> >>>> Could you use 'r' instead of 'rc' ? The later is reserved for libxl >>>> error codes while the former is for system and libxc calls. >>> >>> Of course I can, but I did look at the rest of the function and >>> found that it uses "ret" for the purpose of what you now say >>> "rc" ought to be used for. Seeing "ret", I decided to avoid it >>> (knowing you use different names for different kinds of return >>> values). While I've switched to "r" for now, I'd be rather >>> inclined to re-use "ret" instead. (Or actually, as per the >>> remark further down, I can get away without any local variable >>> then.) >> >> I know there's quite a few (many?) coding style issue in libxl. I'm >> trying to prevent new issue without asking to fix the existing one. >> The use of "ret" is an already existing issue, so I'm fine with it been >> use in this patch for libxl error code in the function. >> >> BTW, you still need to store the return value of xc_shadow_control() >> into a "r" variable before checking it for error. > > Are you saying that > > if (xc_shadow_control(ctx->xch, domid, > XEN_DOMCTL_SHADOW_OP_SET_ALLOCATION, > NULL, 0, &shadow_mb, 0, NULL)) { > > is not acceptable, style-wise? Oh, there is indeed such a rule under "ERROR HANDLING". Which means ... > If indeed you are, please disambiguate > your statement above regarding the use of "ret": May I or may I not > use it? IOW do I need to introduce "r", or can I get away with the > existing local variables. ... I need this to be clarified. Jan