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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?IOUHlnXG0Om4Ac1Er3Suqlvpud0m2e6nFbpu1I131/D8iyl5gPGIW/q3Vfil?= =?us-ascii?Q?MJPX9OlswjHHIO4LEp/ImH03YxhOm3HbPXPRR+L9m9Pf7Hz5f0+QNhFNvm0o?= =?us-ascii?Q?SZ1ZiFj9xnCOVrM/A+p8qvRyTJicnxoPtjpW/qGsYuCMLwC5eERfDlt3D3OJ?= =?us-ascii?Q?oe1oLQWpOTemEcNdKl2QbmXZywRf84dp+nj96GOD3rSNF5Nt6vnEPfKjB0Ts?= =?us-ascii?Q?xbMaxyUtfZYu2QHQ1Ke8NrB5x/QjLCAUonYYVyRtGYQ52cTNZizFmp6M67qO?= =?us-ascii?Q?FEXfa93coMr00nNFNL0Xkyu50uKV/dlyk6jS9yIP+8FeMvzKLbVNYTGdHDfv?= =?us-ascii?Q?BbglbWmcm5W0JY5naaZ+OM59M4XDI7N2Rtivr75cbaxTPcrFP7e+Zy+dooJd?= =?us-ascii?Q?V3xDCx16N3lJu1Vh+p9E1Dwv8Ovg14DOSyRjHX4JlRkKeb3sKcGOF9YARWAr?= =?us-ascii?Q?o+7WM6xHDM45DqJkdIzgZ5RB5zufMPIC46moiM2Jv/xo9AbJ4zb8aJikp7px?= =?us-ascii?Q?Z1xq7STtGpGvLF96uvNchD6v0HU3TkR1QFt9dZaL7iDGT25/bvTP3Zg2i5mE?= =?us-ascii?Q?vlG5rRfZDJZ9ebVloZtYGlADOWSM6ATZekIaP8NcdLbIkORzeI/5j2C/MMWR?= =?us-ascii?Q?OHtLBB/B0WBoDJcSO73RQVtFaD5kTz7r8hRmRuhRjokffJYB0WqaNVPt8OTa?= =?us-ascii?Q?mdesSbB7NPuUeFvwsQnL42qC5QjhP6GI2RsMy7uLh9dSs1tiRrYue4X5DbKG?= =?us-ascii?Q?5hDr6TdDBfpeuGt/z0914duY2w6u1cJytyLnQcEnSW1A66CZBgrS43NH/6mb?= =?us-ascii?Q?WGJOqh6uRyTbaOhlbBnyyOifWvP71Zav89j+YuDI2PZ2l6yuDHyAoisqbc1N?= =?us-ascii?Q?YgjA17d3ewejkUoAa2fozzlT4ASlYEA0/vb6Ty/bo0OGXPVQMzqp82GQQ2MR?= =?us-ascii?Q?/z6yg1OVgYutTTX1C+JMskrqxBLyJRLnqKe4/blqmSUhgJ+Ojj+8YFYxC/Fz?= =?us-ascii?Q?p0sMwNgfWXTtsv3ONHU37rbdOw/o9Fjp/00R33TF9BW64Np5PM+jcKaOcC0a?= =?us-ascii?Q?gNaZOkGT0NF02kIbzF4jrRrux6JIQOAqkh3FnDSE9ZWBlk7llYD3DLkJ8Vlj?= =?us-ascii?Q?rydbI7CfMEo0J5RRuKlVE8c0PxdcPLbrctzbYNtT+msLo4tbZiNo/JF728bg?= =?us-ascii?Q?VH7C5EgIvCfloyHB1+GFqTUWD9Bd/FxuxrEy8TJ1uo0vFfCvgKocf2bFvMCG?= =?us-ascii?Q?Sf6T0Wf3/RV9E9sWKzt3WPF3EJddisttsrgBAdqv187j1/3ygyPCstJoRY6i?= =?us-ascii?Q?bItPvgXNGm/A+2dKtt5YxEEPn+pLISrVH/8ytD/2LfqsGvMmmoE4w7+KejxS?= =?us-ascii?Q?MeafwcN6mzuYKNcZXFs0MuGLCl/9DwOKMiI0LgKxbuhJ1/LU1RH5GCGZTCAb?= =?us-ascii?Q?VpZH4rCTQWKGeuLuswyEXTUME1tOUbhlnetEqMjlXDOK08dA2DjEnlLHiMtj?= =?us-ascii?Q?zkC+7qNnRUVeXrPPeKmsvV5V29Xy6+VfExkMJOBYR1Cy4cVykADFrXYS7x4f?= =?us-ascii?Q?4ZH3HbT/8l9d+PY1SUWt6qjr+yDS0Xq/zIG3YNtUB9Xxiv72XP/meh7lZYfC?= =?us-ascii?Q?ckAO+c6fFPyvJqVe2fK5D9n4W9/EN/nyxDl2ijgvHmK2Ca/3IfJKZwiMDVZf?= =?us-ascii?Q?Wp3UFkgiVWDgMYb1gwU0JEDWcEOvgBIL4Tdtl/H2aIMXCJMAc45eUI6PghYF?= =?us-ascii?Q?7a4bwkKGqQ=3D=3D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: bb0fd749-ad78-40d2-3b93-08de57b9f613 X-MS-Exchange-CrossTenant-AuthSource: LV8PR12MB9620.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 20 Jan 2026 00:22:14.3908 (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: pWfYpx2Td18qAN8xqnEf4Mo37MIQu8YlQ39lsKQXtW+Sx3F4Vi/f0jeim73po6MF X-MS-Exchange-Transport-CrossTenantHeadersStamped: DM6PR12MB4315 On Wed, Jan 14, 2026 at 05:12:43PM -0800, Nicolin Chen wrote: > A vSTE may have three configuration types: Abort, Bypass, and Translate. > > An Abort vSTE wouldn't enable ATS, but the other two might. > > It makes sense for a Transalte vSTE to rely on the guest vSTE.EATS field. > > For a Bypass vSTE, it would end up with an S2-only physical STE, similar > to an attachment to a regular S2 domain. However, the nested case always > disables ATS following the Bypass vSTE, while the regular S2 case always > enables ATS so long as arm_smmu_ats_supported(master) == true. > > Note that ATS is needed for certain VM centric workloads and historically > non-vSMMU cases have relied on this automatic enablement. So, having the > nested case behave differently causes problems. > > To fix that, add a condition to disable_ats, so that it might enable ATS > for a Bypass vSTE, aligning with the regular S2 case. > > Fixes: f27298a82ba0 ("iommu/arm-smmu-v3: Allow ATS for IOMMU_DOMAIN_NESTED") > Cc: stable@vger.kernel.org > Suggested-by: Jason Gunthorpe > Signed-off-by: Nicolin Chen > --- > drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-iommufd.c | 4 +++- > 1 file changed, 3 insertions(+), 1 deletion(-) Reviewed-by: Jason Gunthorpe Jason