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X-MS-Exchange-AntiSpam-MessageData: =?utf-8?B?YU9kVWJLdDJiYkFjMEVBWEJROWZFdk91YU5lajYxL0VrdFVxcjZYSzZzQ1k2?= =?utf-8?B?NGNSYTE0bHNwemhZVUpTaTYwVFlXRWdHWmhuRnBnSE1PMHdUMGVnY3ZjUzIy?= =?utf-8?B?OUhLWjN3VkJlMG8zU3JGYmg0TTR2TXByN25oVnlZSkk1dE0yREVRS0FwbFU3?= =?utf-8?B?bHBFMThCQkw0WktEQ3c3TXBuN1BFSHdDOGhzQ2tEVDBKWjEzNWV5bTM0bDY5?= =?utf-8?B?YmI4VHE2YzRhcTFNS00zdDRybVlQUHI5UktJQ3Ztc0xXRTlIYk9vTkdmdkQ1?= =?utf-8?B?cnIwbmI1cnZlcEJlMTdpTzJZemd1SjkwaWJNZjEvOEI5N2FGOGNtNVJJVVcx?= =?utf-8?B?dmxYM1UraWdBVGhLVU9IY1JjU21LaVRxRVA0b1R6blFpS2lUWktkTkpOUDVh?= =?utf-8?B?ZWoydWFEeExOS0gxdFhrZXdjdnZLRktZRllJYlJYa2hpVzJzZHBnS2RId0NV?= =?utf-8?B?MFVDWnY1ZjJKcTk5QXhzVVdkYlppMS94K3NzeGpZZmZGc3JNVTZOVUpZRTRF?= =?utf-8?B?ZXRacjZxNjJHZHQzOVpCbmRhMENFOWRqT2Rna1F4VmxycmVlNjhmK3gvWW1J?= =?utf-8?B?Z1pPYUdwekdHNDVMZkxkWHVFK01hOFVMSzZSWnB0N0srTFB4bWpUaTJ3bitU?= =?utf-8?B?cnU5ZVVnR1VqLytFL2hSV08vcEp1Y1RiSGNkOURPQkk0NUJkWHpCalc3Wml2?= =?utf-8?B?dVFvcGQ3aGQ5enQ5V1VPM1NBN0pwaHd4ZUtWbU13a1pNc1U5QmQzMWxZMTFo?= =?utf-8?B?OGRKYTUxY1dTdVRXRTdRWStxZnBLK1JkWGlJTDNpV3hqTFlEZXhNOGQ3RXdt?= =?utf-8?B?N2s5Z09FdGgyRzlpNjRncVdzVDNDaGY0ZmNVV2JzTWFIUmxTeHVKZGQyR3dW?= =?utf-8?B?VWJqVmhVOU42WUd1RlVFZWxhandJQTI3dm1YQlNLcE1zbDJDMUw4WjFGWWxj?= =?utf-8?B?aWNNWUs0OWhFa1F4NlRpT3dZQ3RqdzhCTjdyNlZZa3pHVHBPUVljUVhzWVZO?= =?utf-8?B?K2lwbEVMeEpTZ2RLUFBkSFBoYWNkK2MwaUw1R3FFOU1hTjd4QlVZZDMwZE8v?= =?utf-8?B?eUxsQXdPWkkrWlNza294b1lSYmlQTklZVXE4OGxUZ1I1bWNMMUd3UWpnSlhG?= =?utf-8?B?VndTU29OWFFKNW5EN3daZGU0OUQrUGFqaG9zL3FxTXdKV3dzVTBUL1JZMWRN?= =?utf-8?B?TWtWOFZBZnc4R1lqb29DbW41VXFRSGtFeitzK2hndUlpUlladm03aDZEa0hp?= =?utf-8?B?RzQ3Nys5NityT29qVTFsQVNxcUg2SFZuYVZxRzJDNm5SN3Zoa1liME1LWVB3?= =?utf-8?B?ZndBN0tTR3JjUENqd0ZwRE5sQUVkMjhFcWNzT29QU2NxSTNnY1I2bG5vUDZr?= =?utf-8?B?QmpjbkJkelRwNFF1R3VqcndyVWV2Tjhhd2RtUWtCWlZSbytMZ0NiU2VTTkxq?= =?utf-8?B?alhDNW95eTBuQVIwTzdRODdtWnR1RC8xTldzU2lNc1Y2TzZHbC94ZG9qdmY2?= =?utf-8?B?YndqbDFZRjY5eUlrL0cyTkpaMWNjK2dnTVV1Ym5oN0pucTFCQk8yMytKclZ3?= =?utf-8?B?ampwblk0dDRNRVdnQlA5OW83SzNkL1pDSlhwTlNUcXI5aWFUUlB1R3l6WS8v?= =?utf-8?B?Y2xxS1ZyZkh2ZDExM09iMmVxS0U4bUh0UjlSSkgzTlFKa05EUm9IUUxJSk01?= =?utf-8?B?d0h5K1FHdmhsMnpUNjNGVEY2cm5sbTc0RElKUTJWQS9JR3djVW5IMkdnVSth?= =?utf-8?B?MlNQZzFKYTJEaGZlSitFQVl4d21SQVVudU03aDVJL2lFd3hTaEZTeG8wRDNU?= =?utf-8?B?YzFUMU1KQWUwRmQxUlR3Zz09?= X-MS-Exchange-CrossTenant-Network-Message-Id: d0a8680f-1ca2-44d2-1a8d-08d8f4f39f91 X-MS-Exchange-CrossTenant-AuthSource: DS7PR03MB5608.namprd03.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 01 Apr 2021 09:50:46.6353 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 335836de-42ef-43a2-b145-348c2ee9ca5b X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: rsAQ0voMslsi3NFsfoHXdcxsmhGxhVDiEknUbp7ZQb18ljDovJjeA/gO0K3MN0a2XIBhRJIILGZKFD2UenlL0w== X-MS-Exchange-Transport-CrossTenantHeadersStamped: DM6PR03MB4059 X-OriginatorOrg: citrix.com On Thu, Apr 01, 2021 at 11:26:03AM +0200, Jan Beulich wrote: > On 01.04.2021 11:00, Roger Pau Monné wrote: > > On Wed, Mar 31, 2021 at 04:52:47PM +0200, Jan Beulich wrote: > >> Unfortunately aa50f45332f1 ("xen: fix for_each_cpu when NR_CPUS=1") has > >> caused quite a bit of fallout with gcc10, e.g. (there are at least two > >> more similar ones, and I didn't bother trying to find them all): > >> > >> In file included from .../xen/include/xen/config.h:13, > >> from : > >> core_parking.c: In function ‘core_parking_power’: > >> .../xen/include/asm/percpu.h:12:51: error: array subscript 1 is above array bounds of ‘long unsigned int[1]’ [-Werror=array-bounds] > >> 12 | (*RELOC_HIDE(&per_cpu__##var, __per_cpu_offset[cpu])) > >> .../xen/include/xen/compiler.h:141:29: note: in definition of macro ‘RELOC_HIDE’ > >> 141 | (typeof(ptr)) (__ptr + (off)); }) > >> | ^~~ > >> core_parking.c:133:39: note: in expansion of macro ‘per_cpu’ > >> 133 | core_tmp = cpumask_weight(per_cpu(cpu_core_mask, cpu)); > >> | ^~~~~~~ > >> In file included from .../xen/include/xen/percpu.h:4, > >> from .../xen/include/asm/msr.h:7, > >> from .../xen/include/asm/time.h:5, > >> from .../xen/include/xen/time.h:76, > >> from .../xen/include/xen/spinlock.h:4, > >> from .../xen/include/xen/cpu.h:5, > >> from core_parking.c:19: > >> .../xen/include/asm/percpu.h:6:22: note: while referencing ‘__per_cpu_offset’ > >> 6 | extern unsigned long __per_cpu_offset[NR_CPUS]; > >> | ^~~~~~~~~~~~~~~~ > > > > At this point, should be consider reverting the original fix from the > > 4.15 branch, so that we don't release something that's build broken > > with gcc 10? > > Well, I didn't propose reverting (or taking this fix) because I think > build breakage is better than runtime breakage. But in the end, Ian, > it's up to you. Oh, right, sorry. The build issue only happens with NR_CPUS=1, in which case I agree, there's no need to do anything in 4.15 IMO. Sorry for bothering. Roger.