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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?QdwrJXSLawVGBG/bXHd2PMA0H9sT7cpKEtuFO80pVp18adxCN+fxbsMQbttG?= =?us-ascii?Q?WAk891VJ2fiqUusdDo+wmJsURZrvlYUN9WKAGkPA2s4LFyxGNI0dNxG9xjpv?= =?us-ascii?Q?Wv0Pt/HUaDqkHGzhHlKZffU0WMRpKl1lMz9nRLEK9coJ5Evh31Kmz+3xPpdN?= =?us-ascii?Q?gX2Sw2v4a1q3XhBRS1EzAMKtGo15nMRj5/mXL6HKrVMXEIrwguKSi8vtOK68?= =?us-ascii?Q?N8G2XmD7cBEoxrUVDpJy0KFJOsMfCgYYboO/Oq8QMm8NXu6FQyym+/Mu53yQ?= =?us-ascii?Q?aSHkfIFaQq8XjRz1Gvl0uUCIRCB7SGflcwMFHX1ZlQ0AsNCSj3odjcL+GY3k?= =?us-ascii?Q?HN27klYD06AXDaKxZHT83PrtiYdsZkWKvAX1e30FBoFALjo56X9jnu9I1IRR?= =?us-ascii?Q?kDfo0nQxOGhwWBMWsm0V8pKJKkHL3HsBEOY0VRXa5lYIUPU6GSxAR6uqmRLD?= =?us-ascii?Q?rjLoSmemnohU9myFnhG+OJiPleENT/S/PkMqvXiV0rPPLhm/GXX50mD7DRU7?= =?us-ascii?Q?SJfz1ZXo/Hk7sflloo53nAdvtG+RdGoZ3UMkZDd8XNCU5wlwfTbAvaAamiB9?= =?us-ascii?Q?XC2CZMvQHC4l5xygOjMY7jy6eVaW04rzqT04b4Vu/svu39Awvc/2AQnw/8fX?= =?us-ascii?Q?T4i6plgFO39vlQi0ClTbOfkwsD1qW2FN8AYbYDOdWiqyIsg0QbmVYfhEtnWO?= =?us-ascii?Q?7UFgr6rVu5epUghVu+bhg+8R/fBM32WOp9TDmmjQxzBzZKE1TfPPyXrr51lw?= =?us-ascii?Q?vBeEtYipmcKzcPzhVbkgac4JS1VNdHfK/8K3WOh7aON77sxahO8VPHxKplaG?= =?us-ascii?Q?czZC7SzelSixscd3mxZNjn0W3rml/QBMfRTkY8W4QFzbhgdw/BWFEVE+9QFr?= =?us-ascii?Q?ujpmBa5TBLA8lG4Cs594UNUZDBP8jOkixovFCFm/0vBEFT65Wir4iQ3XmHkD?= =?us-ascii?Q?hdyiwYpGc5lZyHw93KeF6yz2NFiV9vHdQvObhrW8k5MtQCN0k8an34pZ4Nsu?= =?us-ascii?Q?oDlS0qseDe/xFYs/vNGrtHK7oU69P5G1G28Vei/P4aRFfs3zTOVzNJZfjkXM?= =?us-ascii?Q?GLxzNqVLYUxeneT0Wix3k330oFmj9FSeJa3J5/3YuIYjKaOqasxWxAUJRxff?= =?us-ascii?Q?Ff1l+C7kD8Jhe51xmqzS6CPgPgeFKsyItes49bNoPpprWMrxc30mdjLg0VmW?= =?us-ascii?Q?c3GjRox2SMyEVEj/XjaDPGvbuWlyyQgXVxUmOydtxYqT1Crz1832R/tFEkGz?= =?us-ascii?Q?FjF4BSwRMUHjbClkMNrZ7zStsOLC0S6F1cu5xvKb+2vOTJoUY+QRAPJ1LPxG?= =?us-ascii?Q?I7dglfDqN2ZxkVFb+mT/lFq1dZQ9sa3zw3FF8EhBGkcWV/Mn1tcXS1r0ul1n?= =?us-ascii?Q?xM/lfFsNh10pYz/kTGDA/0EoRHEAoCQifFGBWsE2zzggzncIZnvHF5/I+RXP?= =?us-ascii?Q?6uwu/WysXPYNBBxver1ujxxEnc4fiPWq+hRVJM0iI+MX5YZsmO8R2U4AGK7m?= =?us-ascii?Q?Itbj0Jo26gAfNCnzocOSD/AGko00u3oR1l2JXd8Bi5tKDWbWPwdBRBue6phR?= =?us-ascii?Q?UZUwcWtLkLZf/FgBFS32pPC9r88HSsOaGfihwnGOXdZOnrfTnAQCqE7kFvkB?= =?us-ascii?Q?GwHi4GUBey89bOnojATiaYghUMCFDR9LuK6JKyvqaSuwzJbPbEj9GF3justY?= =?us-ascii?Q?+3gMk8fmXW5+X5VNWR/wYHQfa/pbmvDHpP2MbepVF79OXuMAIa5O+GdoS5Ya?= =?us-ascii?Q?ohfoIyf5cg=3D=3D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: df672854-cb1b-442e-dec4-08debba59373 X-MS-Exchange-CrossTenant-AuthSource: BL0PR12MB2370.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 27 May 2026 04:08:15.7591 (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: qjKyh+VuNfcW87oSbg2ahnT2fWCpN+oh9b7HjN00B4rCvssgsMi58WfhsQTHbm2sjNGtsjAqYx1vPw3uq/a3ig== X-MS-Exchange-Transport-CrossTenantHeadersStamped: SJ1PR12MB6218 On Tue, May 26, 2026 at 04:21:30PM +0800, Alison Schofield wrote: > On Fri, May 22, 2026 at 01:44:57PM +0800, Richard Cheng wrote: > > cxl_test allocates synthetic CFMWS HPA windows from a gen_pool with > > SZ_256M alignment. On arm64 with CONFIG_ARM64_64K_PAGES=y and > > CONFIG_PGTABLE_LEVELS=3, PMD_SIZE is 512M, so every CXL region carved > > from a volatile window inherits a non-PMD-aligned start, and > > cxl_dax_region_probe() -> alloc_dax_region() fails: > > > > """ > > cxl_dax_region dax_region1: probe with driver cxl_dax_region failed > > with error -12 > > """ > > > > Enforce that every volatile mock CFMWS is PMD-aligned in both start and > > size > > > > Reviewed-by: Dave Jiang > > Acked-by: Kai-Heng Feng > > Signed-off-by: Richard Cheng > > --- > > Changelog: > > > > v2->v3: > > - Correct hunk headers > > - Add base commit SHA > > > > v1->v2: > > - Reframe from "fix start alignment" to "enforce PMD invariant for > > volatile CFMWS" > > - Bump cfmws5.window_size to max(SZ_256M, PMD_SIZE) > > - Gate populate_cedt() alignment on > > ACPI_CEDT_CFMWS_RESTRICT_VOLATILE so PMEM windows stay at SZ_256M > > - Add BUILD_BUG_ON for MOCK_AUTO_REGION_SIZE_DEFAULT v.s. PMD_SIZE > > in cxl_test_init() > > > > Best regards, > > Richard Cheng. > > --- > > tools/testing/cxl/test/cxl.c | 9 +++++++-- > > 1 file changed, 7 insertions(+), 2 deletions(-) > > > > diff --git a/tools/testing/cxl/test/cxl.c b/tools/testing/cxl/test/cxl.c > > index 418669927fb0..7a1105f9a0bb 100644 > > --- a/tools/testing/cxl/test/cxl.c > > +++ b/tools/testing/cxl/test/cxl.c > > @@ -318,7 +318,7 @@ static struct { > > .restrictions = ACPI_CEDT_CFMWS_RESTRICT_HOSTONLYMEM | > > ACPI_CEDT_CFMWS_RESTRICT_VOLATILE, > > .qtg_id = FAKE_QTG_ID, > > - .window_size = SZ_256M, > > + .window_size = SZ_256M > PMD_SIZE ? SZ_256M : PMD_SIZE, > > Why not this: max_t(resource_size_t, SZ_256M, PMD_SIZE) > Hi Alison, Thanks for the feedback, but I doubt this will work. "max_t()" expands to a statement expression, which isn't a constant expression so it can't be used in this file-scope static initializer. I did the change and compile, the error is """ include/linux/minmax.h:86:9: error: braced-group within expression allowed only inside a function 86 | ({ type ux = (x); type uy = (y); __cmp(op, ux, uy); }) | ^ test/cxl.c:295:40: note: in expansion of macro 'max_t' 295 | .window_size = max_t(resource_size_t, SZ_256M, PMD_SIZE), """ So I don't think this approach works, I would like to stick to ternary form if that's ok for you. > > > }, > > .target = { 3 }, > > }, > > @@ -495,9 +495,12 @@ static int populate_cedt(void) > > > > for (i = cfmws_start; i <= cfmws_end; i++) { > > struct acpi_cedt_cfmws *window = mock_cfmws[i]; > > + int align = SZ_256M; > > > > cfmws_elc_update(window, i); > > - res = alloc_mock_res(window->window_size, SZ_256M); > > + if (window->restrictions & ACPI_CEDT_CFMWS_RESTRICT_VOLATILE) > > + align = max_t(int, SZ_256M, PMD_SIZE); > > + res = alloc_mock_res(window->window_size, align); > > if (!res) > > return -ENOMEM; > > window->base_hpa = res->range.start; > > @@ -1826,6 +1829,8 @@ static __init int cxl_test_init(void) > > int rc, i; > > struct range mappable; > > > > + BUILD_BUG_ON(!IS_ALIGNED(MOCK_AUTO_REGION_SIZE_DEFAULT, PMD_SIZE)); > > The rule we need to enforce is tha the actual auto region size is > PMD aligned, not the default definition. So I think this needs to > be a runtime check of IS_ALIGNED(mock_auto_region_size, PMD_SIZE). > > -- Alison > Thanks for the catch, I'll fix this and send a v4 to make it runtime check. Do you prefer WARN_ON_ONCE() to be ammend or no? I mean """ if (!IS_ALIGNED(mock_auto_region_size, PMD_SIZE)) return -EINVAL; """ or """ if (WARN_ON_ONCE(!IS_ALIGNED(mock_auto_region_size, PMD_SIZE))) return -EINVAL; """ Which one do you prefer ? or any other idea ? please let me know and I'll make the change. Best regards, Richard Cheng. > > + > > cxl_acpi_test(); > > cxl_core_test(); > > cxl_mem_test(); > > > > base-commit: 6779b50faa562e6cca1aa6a4649a4d764c6c7e28 > > -- > > 2.43.0 > >