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X-OriginatorOrg: amd.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 22 Jan 2026 17:03:51.7012 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: cb57eabf-221a-40ca-f1c1-08de59d837da X-MS-Exchange-CrossTenant-Id: 3dd8961f-e488-4e60-8e11-a82d994e183d X-MS-Exchange-CrossTenant-OriginalAttributedTenantConnectingIp: TenantId=3dd8961f-e488-4e60-8e11-a82d994e183d;Ip=[165.204.84.17];Helo=[satlexmb07.amd.com] X-MS-Exchange-CrossTenant-AuthSource: BY1PEPF0001AE17.namprd04.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: CY5PR12MB6598 On 2026-01-22 11:57, Roger Pau Monné wrote: > On Thu, Jan 22, 2026 at 09:40:01AM -0500, Jason Andryuk wrote: >> On 2026-01-21 12:49, Roger Pau Monné wrote: >>> I haven't tested it yet to see whether that's OK to do on PV, I would >>> think PV and PVH would be the same here, since the setting of the >>> xenstore target value is based in the return of >>> XENMEM_current_reservation for both. >> >> On a system with 32GB and dom0=pvh dom0_mem=7G: >> >> [ 0.295201] xen:balloon: current_pages: 1835007 get_num_physpages 8220126 >> xen_released_pages 6385120 >> [ 0.295201] ------------[ cut here ]------------ >> [ 0.295201] Released pages underflow current target >> >> 8220126 - 6385120 = 1835006 >> >> And also for PV: >> >> [ 1.406923] xen:balloon: current_pages: 1835008 get_num_physpages 8220127 >> xen_released_pages 6385120 >> [ 1.406928] ------------[ cut here ]------------ >> [ 1.406931] Released pages underflow current target >> >> >> So we don't want to subtract xen_released_pages for dom0. Is >> xen_released_pages expected to be non-zero for a domU? > > Oh, yes. In fact I think the patch here is wrong for PV dom0, as it > shouldn't subtract xen_released_pages from xen_start_info->nr_pages. > I will need to send v2. To be clear, the numbers and warning are from the follow on current_reservation patch. Regards, Jason