On 08.07.2024 11:08, Roger Pau Monné wrote: > On Mon, Jul 08, 2024 at 10:37:22AM +0200, Jan Beulich wrote: >> On 08.07.2024 10:15, Jürgen Groß wrote: >>> I've got an internal report about failures in dom0 when booting with >>> Xen on a Thinkpad P14s Gen 3 AMD (kernel 6.9). >>> >>> With some debugging I've found that the UCSI driver seems to fail to >>> map MFN feec2 as iomem, as the hypervisor is denying this mapping due >>> to being part of the MSI space. The mapping attempt seems to be the >>> result of an ACPI call of the UCSI driver: >>> >>> [ 44.575345] RIP: e030:xen_mc_flush+0x1e8/0x2b0 >>> [ 44.575418] xen_leave_lazy_mmu+0x15/0x60 >>> [ 44.575425] vmap_range_noflush+0x408/0x6f0 >>> [ 44.575438] __ioremap_caller+0x20d/0x350 >>> [ 44.575450] acpi_os_map_iomem+0x1a3/0x1c0 >>> [ 44.575454] acpi_ex_system_memory_space_handler+0x229/0x3f0 >>> [ 44.575464] acpi_ev_address_space_dispatch+0x17e/0x4c0 >>> [ 44.575474] acpi_ex_access_region+0x28a/0x510 >>> [ 44.575479] acpi_ex_field_datum_io+0x95/0x5c0 >>> [ 44.575482] acpi_ex_extract_from_field+0x36b/0x4e0 >>> [ 44.575490] acpi_ex_read_data_from_field+0xcb/0x430 >>> [ 44.575493] acpi_ex_resolve_node_to_value+0x2e0/0x530 >>> [ 44.575496] acpi_ex_resolve_to_value+0x1e7/0x550 >>> [ 44.575499] acpi_ds_evaluate_name_path+0x107/0x170 >>> [ 44.575505] acpi_ds_exec_end_op+0x392/0x860 >>> [ 44.575508] acpi_ps_parse_loop+0x268/0xa30 >>> [ 44.575515] acpi_ps_parse_aml+0x221/0x5e0 >>> [ 44.575518] acpi_ps_execute_method+0x171/0x3e0 >>> [ 44.575522] acpi_ns_evaluate+0x174/0x5d0 >>> [ 44.575525] acpi_evaluate_object+0x167/0x440 >>> [ 44.575529] acpi_evaluate_dsm+0xb6/0x130 >>> [ 44.575541] ucsi_acpi_dsm+0x53/0x80 >>> [ 44.575546] ucsi_acpi_read+0x2e/0x60 >>> [ 44.575550] ucsi_register+0x24/0xa0 >>> [ 44.575555] ucsi_acpi_probe+0x162/0x1e3 >>> [ 44.575559] platform_probe+0x48/0x90 >>> [ 44.575567] really_probe+0xde/0x340 >>> [ 44.575579] __driver_probe_device+0x78/0x110 >>> [ 44.575581] driver_probe_device+0x1f/0x90 >>> [ 44.575584] __driver_attach+0xd2/0x1c0 >>> [ 44.575587] bus_for_each_dev+0x77/0xc0 >>> [ 44.575590] bus_add_driver+0x112/0x1f0 >>> [ 44.575593] driver_register+0x72/0xd0 >>> [ 44.575600] do_one_initcall+0x48/0x300 >>> [ 44.575607] do_init_module+0x60/0x220 >>> [ 44.575615] __do_sys_init_module+0x17f/0x1b0 >>> [ 44.575623] do_syscall_64+0x82/0x170 >>> [ 44.575685] 1 of 1 multicall(s) failed: cpu 4 >>> [ 44.575695] call 1: op=1 result=-1 >>> caller=xen_extend_mmu_update+0x4e/0xd0 >>> pars=ffff888267e25ad0 1 0 7ff0 args=9ba37a678 80000000feec2073 >>> >>> The pte value of the mmu_update call is 80000000feec2073, which is rejected >>> by >>> the hypervisor with -EPERM. >>> >>> Before diving deep into the UCSI internals, is it possible that the >>> hypervisor >>> needs some update (IOW: could it be the mapping attempt should rather be >>> honored, as there might be an I/O resources at this position which dom0 >>> needs >>> to access for using the related hardware?) >> >> Adding to Andrew's reply: Is there any BAR in the system covering that >> address? >> Or is it rather ACPI "making up" that address (which would remind me of >> IO-APIC >> space being accessed by certain incarnations of ACPI, resulting in similar >> issues)? > > So you think ACPI is using some kind of backdoor to access the local > APIC registers?
No, I'm wondering if they're trying to access *something*. As it stands we don't even know what kind of access is intended; all we know is that they're trying to map that page (and maybe adjacent ones). > It's my understanding the local APIC registers are all located in the > first page of the range (0xfee00). It would also be weird because > ACPI doesn't know whether the APIC is in x2APIC mode. Indeed. Jan
