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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?1NHbQB/1DYwWG/YyhLgjHH0saqnRk3zkL63PxoZ31GKuDFYtqtFPv6mzLzEz?= =?us-ascii?Q?x5N+lq1nWE8bACy8DlzvXHFwk+LDwnO9IKQFerBVpyElxqO9rMe0NaYah/jW?= =?us-ascii?Q?k5YAL6ihjtpn09W/dl6qFKUIjHxJf86m9nlwcB+11W5fRUGvaCLmIj5ZdqKQ?= =?us-ascii?Q?b6Gvan9z+BopDQUdMRs27L+ovywAZEmnGPTeSk+m37hDhsTnjuvSnv7+dJ6Q?= =?us-ascii?Q?J/D9xkUgq4GLAf1TA2cv7AAqUGvvoCtLf/gI2RLMuPbx5E7H7gjSpPFsgXY0?= =?us-ascii?Q?qywQY2sAgRyLzzAD8wgciiEDBg6xsY9WKhDYDZCkrOlNuOaJtBdHMlxNuTi0?= =?us-ascii?Q?yjgMsnDn7ukd8DYSLAHH8onYXIy1W3f0UJuwG1KSoVdfF3QC0dX0k9yy62SO?= =?us-ascii?Q?LUiDTto/zzJdtzuTE0r1m3tZ6OfPN8FDzEkRb85tluWmsBJcHJAmn/VEXVM0?= =?us-ascii?Q?TVFU9e2W6pwJo/I4eMfGn5wmmvhcGPBfkG7YfInMXZbXJYl9a8nGePBQjTfv?= =?us-ascii?Q?s2z51dcs4rzgd4I3dneiR1a+p22jrLNaAxrJVAWQeJD+E6dfveirIgvzK9mM?= =?us-ascii?Q?j6V0PBSd70vtODX66/JTQxKHMgKsUpFtK1MvXrLpJVsstM1zpSlYpqDFYFRp?= =?us-ascii?Q?6QqypRKy/zg22Qa4oKdXOFlm2xIuJ/rk5LD4E5zR1+PjXHZ12hutdUGn3pPv?= =?us-ascii?Q?6kHp/p7lOEBfkEZ4bX/YzwRh6FBZD8zi9ydkV4Sn3qghyyzwSaZ6VFif2dW4?= =?us-ascii?Q?O22+96e6mKs8BzVCS58Xoob9KrLszHdS/DIN9Uv0C4kfRiv3o13OwnxMIhVY?= =?us-ascii?Q?Jt0Ul0hKi3HChg2DrEGrdfR3St+suGZ1nSFxrk70z8GcCq/t6yLHrOzJVbJv?= =?us-ascii?Q?Lu5I9rz49V7hiWPJMWZy+EwBAbO/nPRPZ6pXn7OJenoT1gi1ckpMpJEkvw1Y?= =?us-ascii?Q?Yznum5t08gUY8SYINA+NZyzS0fdbUkb5p207MuW6ri5g51Wk4U9wf0DR8Qt9?= =?us-ascii?Q?UFMAkL18X6KKKChtPo/dbd3p8k/11svfoLZDCPJecXkFqvUr10EvZrYjedN9?= =?us-ascii?Q?v1qj6ScRSGqyqcsUFJ/DRiN8h60r0BMA5Yev9m0zBDsdfqSnpLhVRdVERDul?= =?us-ascii?Q?mqNmYPA2bkYBImhbXmLEUh+F4+/hROrAVTFmpoCCYxFI1eswe5G3YjOk4uo6?= =?us-ascii?Q?zcAGwVUWmsijpWdHj+ztFuQiYHgcnISuKLztaj302e8RamERrc65MTQKxH33?= =?us-ascii?Q?aqPBWgrEEHuX83OxigQCBarwTSsSjFKgBp4CNudlDG1506CwQGc7B1c28Ywv?= =?us-ascii?Q?BFy6RV4PmODnRIpmoY7LcGpjViGWrR3mtimeqyibhWwzrp3vD4XGyvKJmpPg?= =?us-ascii?Q?V0hXFG3aj2WhHl/ZsYC2oWniVPSc9kgotxzc4yEuhexdyBwqsv8EQ+d1zKwF?= =?us-ascii?Q?Jt91HRIaDCNHGfvPsgide6QsrmfN6jcWRD/nD0QEBivIph0DsMbroKYcyDY7?= =?us-ascii?Q?10W3asldHSmRZzz13Y224VQzBrznufYx4x/UwTyUVi2XIaWpfvr+9MUSyErj?= =?us-ascii?Q?6uCKirBf31TLDPgy6CTbTMhk8KunK/W+Wfj8I4VOE95borvcvOexVUVR7frf?= =?us-ascii?Q?FfOZEueiLbyvxKbm8dJWspoTIeC+R4lnGY6N8ykqH0iEQAwGt41t5cx25D9p?= =?us-ascii?Q?jUf06kxhyO+qQnGCm7pxfrinmrwRvagYpGjVuHUUfMxwJQS2tH2j2siNdEJV?= =?us-ascii?Q?r1+IO164Mg=3D=3D?= X-OriginatorOrg: suse.com X-MS-Exchange-CrossTenant-Network-Message-Id: 2e4c1152-6cf5-4c75-4d36-08da3815d0cc X-MS-Exchange-CrossTenant-AuthSource: VE1PR04MB6560.eurprd04.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 17 May 2022 14:59:17.6271 (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: bpf9GdyMePhiX7wa2ZFoyLDtjY+UKcH4RjRII2eSTDaSjozne6HhgklMFo5FGMiZnO4sbTW0XiW+qvCvOb7ocw== X-MS-Exchange-Transport-CrossTenantHeadersStamped: DB9PR04MB9628 On 11.05.2022 16:21, Bertrand Marquis wrote: >> On 11 May 2022, at 13:11, George Dunlap wrote= : >>> On May 11, 2022, at 9:34 AM, Julien Grall wrote: >>> On 11/05/2022 07:30, Lin Liu =EF=BC=88=E5=88=98=E6=9E=97=EF=BC=89 wrote= : >>>> On 10/05/2022 11:15, Lin Liu wrote: >>>>> static inline void put_unaligned_be16(uint16_t val, void *p) >>>>> { >>>>> - *(__force __be16*)p =3D cpu_to_be16(val); >>>>> + *(__be16 *)p =3D cpu_to_be16(val); >>>>>> Why did you drop the __force? >>>> Google told me __force is used in linux kernel to suppress warning in = sparse, >>>> https://stackoverflow.com/questions/53120610/what-does-the-attribute-f= orce-do >>>> Is sparse also used in xen? >>> >>> I am not aware of any use of Sparse in Xen, but it would technically be= possible. >>> >>> However, my point here is more that this change seems to be unrelated t= o what the patch is meant to do (i.e. switching to byteswap). So if it is u= nnecessary, then it should be dropped from this patch. >> >> I think making people pull little changes like this out into separate pa= tches is asking too much. It=E2=80=99s a lot of extra effort on the part of= the submitter for basically no value. We commonly do little clean-ups like= this in patches, and just require a comment at the bottom, like this: >> >> 8<=E2=80=94 >> >> While here: >> - Drop =E2=80=98_force=E2=80=99 keyword, which is only needed when runni= ng the Sparse analysis tool >> >> =E2=80=94>8 >> >> I do agree that minor changes like this need to be described, so that pe= ople 5 years from now have some hope of figuring out what=E2=80=99s going o= n. >=20 > I fully agree here. The effort involved by splitting a patch in several o= nes (both for the > contributor and the maintainers) means it should be prevented unless the = original patch > could not be reviewed as is (patch to long or to complex to test for exam= ple but there > might be other valid cases). This is fine for uncontroversial changes, but not in cases like this one. Like Julien, I think we should rather strive towards completing the Linux-inherited annotations like __force. Even without the actual use of sparse they serve a documentation purpose. Jan