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X-MS-Exchange-AntiSpam-MessageData: =?utf-8?B?dFdQcXlkd2dIbllzNllGM2FHWnV4cVpUUDdmQlI5ZUJ0b1prSGhGdEN2enlG?= =?utf-8?B?bWZyaUc4ejVHTnFTL0ZiU1p4NFk3Qm42b1BVdTVyenN1MFVtYXN4cjBNbWhs?= =?utf-8?B?K2ZsUnBsVHk3NCttNUM5dzljMGkrTGJyODJTbzcxUTlxWURqaXNKUkUrQWEv?= =?utf-8?B?b3RkanAzS3dWM0NhSzdzbUdHQmZkdG1FT3cwRVZ5MHdib2lFRUtFelNjRUFo?= =?utf-8?B?VkhaeUZsUzFhRU03WFdzUnpLb2Y5Mk5oWXpnd3djY3ZSSlZqUmFlNCtIdDhI?= =?utf-8?B?WGlWZ2c3L0FDMU9RRVF5WFdiQ3M2dm1BSXhiNjQ5cWRadjMyOFV3YUx6UUd4?= =?utf-8?B?SThxTGdQS2VtRzZWeFNtQm5jRmRUd2pUNkxVYy9CcHUvczRhSTF5MnBUSENP?= =?utf-8?B?RXpZd3Y3MnpuemE1UGNQWE9ZVllyS1c3MGpaK1prYjZiVU1OWlRzUk5zY3ps?= =?utf-8?B?ZHhIQ2lUUFgyYlhNRW5pSTlZNHBJakExVDA5eFNOYms1R0pVY3BLVVFDMDhx?= =?utf-8?B?SStMWHpzNkc3V1U2bHpLZmp0WUhyK0dzNXJta05aM0FLUTJlbDJQWlpvdFdJ?= =?utf-8?B?dWR2VitUbG1iNGJPTUZ1Rmo4RDlXZDRjTlE3UnUySlAwR3U2RVBKV1JidElB?= =?utf-8?B?cG91YStmM3lEb0tSS0NiMVZQMG1IUXEzWTJLdkxndW45S0ZZb2wzL0NaeEVL?= =?utf-8?B?QUZhM0hUM1d6UzVYdFpaSFJlcnl0M3JiMlVwb1lWYVJlWnlPaEF2a0o4UVFO?= =?utf-8?B?YVNlOVFvSGhkV244Vy9WMDU2UzhCZGt0eHhCcEpuZHVGYVBQMW9SYnZlSmRN?= =?utf-8?B?cWdwUGphU3R3cnJPTklUc1N5SkpDUE95eUdzQXlkcEgrdGY4WC9Ud1lUUlhu?= =?utf-8?B?d2JHUlFnVytkSVVRcVYzeWQvVThDL0J2SmhCRDZ2bHhIaHpleDRoQS9TT29E?= =?utf-8?B?aXFVQnp4bUZxUmd2bmZ0U1hUbzJzYXBTNWkxRDA0SHhtNUF3Qm5LTHI3UFl3?= =?utf-8?B?cCsyK0NlYTdNTk1ESktFMnVQMXl1ckM3VytjVXVSR1NuaWtQZzhRNU0vek9l?= =?utf-8?B?R3poVTFqMkNpZjAvbnFydW53a3BYYjN4U0lrRXNXWjMzdjB2NWdCdjYzUXJu?= =?utf-8?B?YXdqbmhOMUl3VDRGN2hFbnZya2pDWjhEd1I0YmYyV1IyUXN4emJUMVdLMVFV?= =?utf-8?B?Y0pmc0g5SzFyQ1JmangrbFVrUDIxRDZRRnpLd0MrejJLakVrejFJNFRpZzJx?= =?utf-8?B?eXAwN0RzYkVuTXh1bGViZ21wN0c4Mm43YmprOUgrZnR6TW1Kci9Sd1h0NTFj?= =?utf-8?B?M3MvZFVFVHgwazREdHR5eWRoRWI4ZXhjZzNEc2p6UnhQUnZPU1FlNEM4US9P?= =?utf-8?B?Q2dzS1RWQWVUTDgrbXBZakwyZk1XNWJYUEJQaHpvbEJ5RmlmQjliV2N0eFhk?= =?utf-8?B?WjV3ai9WS3BUbnJPRVJuNitSYnhKdGJWWWs4aitWYVNPdzVMTjVCVUJxRDl6?= =?utf-8?B?NzNmU3FEakNJRjY1VkEyRW9DZkYwWjN2a3VISmpMeFc0andORFpnVnVFdEY4?= =?utf-8?B?NU02WGlPM1QzSXVzcUk1VkxFOEQ3RTAvMFlNZnY3Z1c5aXVFOUxleWp0b09v?= =?utf-8?B?YjRYVDZvSUZKVlBCM2JJeEQ2UDI0Y3JtNEpNM0duR1BqOGFlTmJQQjJud2Y3?= =?utf-8?B?NkZhUTVPTzNvUG5sZkVYd0x6YVloNUgvaEpENDJMNXYyeTZZeWgwTm1McDl2?= =?utf-8?Q?aSVStxudhnr874GLXAvGK3gJePR7z8/G1XQqnop?= X-MS-Exchange-CrossTenant-Network-Message-Id: fe4f34da-d758-4e8f-9fe1-08d8fb56941f X-MS-Exchange-CrossTenant-AuthSource: BN7PR03MB3618.namprd03.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 09 Apr 2021 12:54:14.5463 (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: kCMbGnSUUbm2WUvUF9NtAEQdBdKRyB67Pe6ud7nYuefwNRoQ4Fy0xcM8xC0dpYl6Jkx9dpzeGsqQTPbqR5YG4UTTHI9v0rNmSdWvHxF/+uQ= X-MS-Exchange-Transport-CrossTenantHeadersStamped: BN8PR03MB4946 X-OriginatorOrg: citrix.com On 08/04/2021 13:21, Jan Beulich wrote: > There is a difference in generated code: xzalloc_bytes() forces > SMP_CACHE_BYTES alignment. I think we not only don't need this here, but > actually don't want it. > > Signed-off-by: Jan Beulich This honestly looks like a backwards step.=C2=A0 In particular, ... > > --- a/xen/common/kexec.c > +++ b/xen/common/kexec.c > @@ -463,7 +463,10 @@ static void * alloc_from_crash_heap(cons > /* Allocate a crash note buffer for a newly onlined cpu. */ > static int kexec_init_cpu_notes(const unsigned long cpu) > { > - Elf_Note * note =3D NULL; > + struct elf_notes { > + Elf_Note first; > + unsigned char more[]; > + } *notes =3D NULL; > int ret =3D 0; > int nr_bytes =3D 0; > =20 > @@ -477,7 +480,8 @@ static int kexec_init_cpu_notes(const un > =20 > /* If we dont care about the position of allocation, malloc. */ > if ( low_crashinfo_mode =3D=3D LOW_CRASHINFO_NONE ) > - note =3D xzalloc_bytes(nr_bytes); > + notes =3D xzalloc_flex_struct(struct elf_notes, more, > + nr_bytes - sizeof(notes->first)); ... this is far more error prone than the code you replaced, seeing as there is now a chance that it can underflow. ~Andrew