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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?OgWVAygHtp34lDt13BxzOcg2ZDaUVckvOYjux5w2FYo9p9e5GeWQDqYWzrAc?= =?us-ascii?Q?5Hc6UQAmUb3dZhAlBRxZnPsd6+ZQHVOlCgsmTfUrv4QrpVFVwaLoYNo39Sxx?= =?us-ascii?Q?g8a6XOz/3MSBmt2JkxJBmx6jzMKfaTHKhsjEr33G0w325UKLoV5O52QSmr6E?= =?us-ascii?Q?xwzqrSzrwabe6HSlUXMHSSkjYouYccBlHtFg/ElrVtD1smxsUjtYBjpOYCba?= =?us-ascii?Q?tqDYRmgv62rXR6SWlmzk4Sz+nLQkWWnKf2ndoBtdrvRrN2LYBROonktR3dSe?= =?us-ascii?Q?k8gZe5/5MkTnMfXJfYFT6NNVb8K1jwfkxO7NPS4c7v0HiZdLulR5MDMBKUdz?= =?us-ascii?Q?XmArLHFEPEtD2yZDmE56e98HeF0Sch0othRMSyr/Ru6DqHB+aBjuj9lRjN6x?= =?us-ascii?Q?gwcUIhzu8C0PEMzXa6wGRXepCdE4DfoC1PtXV9+PI3207Jb4stc5U1TWWEC4?= =?us-ascii?Q?MJQ5ZIxp9xBbUYC9hhbwzkgTCXnRILIqYyRwvwYFf9nC1LwXzCSrG/Sky4B3?= =?us-ascii?Q?QxqrKqGFxAETQryKUgZCVy6qwCtMUh7LSxcnC0KgQNt4agPvNZHacmB2AtDz?= =?us-ascii?Q?W3IMUPgQjHYb1GFr4EVbJCEztZgjHusHuzBOARR6cmqVD7s5q0qIeaTJiQ9o?= =?us-ascii?Q?KH3pp/r7n3thm15IjT7+A39Wq6TzoD4zEYlpmU0TBskrgadGgAFohDFQyJWp?= =?us-ascii?Q?cU59kwbFAAjVfn/7VC8Z7rvAJnYqdje5RUfhIWE2cR5HiyU782M02Oy0qKEg?= =?us-ascii?Q?CH7T+ZjHRqOZFDoAAGt/fE2lBmQKfBUJVD2RNrPlZxHM0QKUm47X5T1cCV/l?= =?us-ascii?Q?c9JSD9JDZq24YSt5cpjwz+uJbupS2ld3m5//DkSXvvQUoxzHu1VRdHP1SNEB?= =?us-ascii?Q?1sWnCt4jUFCiUa9/0rhhWbuLvBK3fA6VwmmBIz5aGFlxvXfK4o0oQnq4RNMn?= =?us-ascii?Q?CYU0k0iHIipNraIX1AlwyhE96RzqOC5RTMMYmTJn/9+FpbYsEYTTQzK46Bjt?= =?us-ascii?Q?7RjyI1uhZn0SOjn51EAYP9UYtQCs8JqRy9RdGCqZfe2rUivyRUcjwuMl3dmx?= =?us-ascii?Q?gKfs/awcMBS4pPzZEEKP/clqLfMtxgegPb9GtRmj4MPvJo1M8jihmNZArE/3?= =?us-ascii?Q?zvKcHsPeQIAdDaI8csVv67Zv5lqj8YU4u/+ZaW0DOaTadsVPK5dpFq6+HOHD?= =?us-ascii?Q?KFJqd3ZqeFq180n+PHTxZUQ0Q19E2/elFeHabb7VXoCcYvmighUXdnAx1slW?= =?us-ascii?Q?r9A9dgC0sXEC2bfGaioRBw9odOqpJcAZIJ4+UtucI9sOAzxifqQ9VVGohx32?= =?us-ascii?Q?aSdMwE6y6rWhQfxT2QJgQqOW8ZUrEHTMEtJP3/EjXU7sEnowLchFj36LOHnS?= =?us-ascii?Q?aUmHQuDOtf3NeuT05JTxYRhmMnjPtzQznLKBs32HoOmsDX52V+pZlwcK0ms2?= =?us-ascii?Q?71p0AZ+Kq1D7ij4RfrKc/dp4kWX/dgbjBEN8MNa81dA4Sx3ad+upvSWkfy2u?= =?us-ascii?Q?yQN29mJeAkPAV5XpoPLParh7XKCJiOmlilaFgQi8mOSuJusN33a2IJsNj/l+?= =?us-ascii?Q?5cPwHB+egeZ9ob8oIOMc20a65/wCesGPMT1qEVKFk7ja8DiXhniUjEnj1O9G?= =?us-ascii?Q?e3mldA0CjFvg6+k0TezPnGu067Ytghdwm301jNuEwApA5v51cRiACI+NuMim?= =?us-ascii?Q?qL3A8qoC7Xn52wvgqhXdc4GaW4Gv1JTPUVkE4PBbEliYqATe?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: aff9faae-399e-49cb-5c20-08de90cd74b0 X-MS-Exchange-CrossTenant-AuthSource: LV8PR12MB9620.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 02 Apr 2026 15:35:23.5716 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 43083d15-7273-40c1-b7db-39efd9ccc17a X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: ZuIhqrO8HeNZJlrcMQ8ugtAUTVxtvIJc/rOPmJ7jpcEqR9whJ4lENHwKQ6wqPIdm X-MS-Exchange-Transport-CrossTenantHeadersStamped: IA4PR12MB9811 On Thu, Apr 02, 2026 at 04:39:08PM +0800, Baolu Lu wrote: > On 4/2/26 14:57, Lu Baolu wrote: > > From: Jason Gunthorpe > > > > This is doing far too much math for the simple task of finding a power > > of 2 that fully spans the given range. Use fls directly on the xor > > which computes the common binary prefix. > > > > Signed-off-by: Jason Gunthorpe > > Link:https://lore.kernel.org/r/4-v1-f175e27af136+11647- > > iommupt_inv_vtd_jgg@nvidia.com > > Signed-off-by: Lu Baolu > > --- > > drivers/iommu/intel/cache.c | 49 ++++++++++++------------------------- > > 1 file changed, 16 insertions(+), 33 deletions(-) > > Hi Joerg, > > Can you please remove this last patch from the pull request? The AI > reviewer reported an issue in this patch. > > https://sashiko.dev/#/patchset/20260402065734.1687476-1-baolu.lu%40linux.intel.com Yeah, that's an interesting remark. I think this is enough to deal with all of its items: - if (unlikely(sz_lg2 >= MAX_AGAW_PFN_WIDTH)) { + if (unlikely(sz_lg2 >= BITS_PER_LONG)) { + /* + * MAX_AGAW_PFN_WIDTH triggers full invalidation in all + * downstream users. + */ *size_order = MAX_AGAW_PFN_WIDTH; return 0; } 1) Yes AGAW_PFN_WIDTH is in "PFN" not byte notation, so it is off by 12 bits and we would errantly move to full invalidation too soon 2) Yes, if sz_lg2 is BITS_PER_LONG the GENMASK explodes, in this case it should trigger full invalidation even if ulong is 32 bits 3) Yes, we sould retain the 0/ULONG_MASK means full invalidation, but this happens properly now because of the above BITS_PER_LONG check so no need to bring back the other check. I'll post an updated patch Jason