From 2bc6b218717b9d08f466f88209251d54bc09b207 Mon Sep 17 00:00:00 2001 From: Fuad Tabba Date: Tue, 22 Sep 2026 19:14:30 +0100 Subject: arm64/boot: Disable trapping of PMZR_EL0 writes to EL2 __init_el2_fgt2() writes one mask to both HDFGRTR2_EL2 and HDFGWTR2_EL2. PMZR_EL0 is write-only, so its trap bit, nPMZR_EL0, exists only in HDFGWTR2_EL2 and is therefore never set: a PMZR_EL0 write from the host traps to EL2, where the nVHE hypervisor has no handler and BUG()s. The kernel never writes PMZR_EL0, but kernel.perf_user_access=1 has the PMU driver set PMUSERENR_EL0.UEN for a task with a user-read event, so a write from EL0 reaches the trap and takes the host down without a panic message. Accumulate the HDFGWTR2_EL2 bits separately, as __init_el2_fgt() already does for HDFGWTR_EL2, and set nPMZR_EL0 with the other FEAT_PMUv3p9 bits. Fixes: 858c7bfcb35e1 ("arm64/boot: Enable EL2 requirements for FEAT_PMUv3p9") Cc: stable@vger.kernel.org Signed-off-by: Fuad Tabba Reviewed-by: Anshuman Khandual Reviewed-by: Oliver Upton Signed-off-by: Will Deacon --- include/xen/interface/callback.h | 85 ++++++++++++++++++++++++++++++++++++++++ 1 file changed, 85 insertions(+) create mode 100644 include/xen/interface/callback.h (limited to 'include/xen/interface/callback.h') diff --git a/include/xen/interface/callback.h b/include/xen/interface/callback.h new file mode 100644 index 000000000..c67822a25 --- /dev/null +++ b/include/xen/interface/callback.h @@ -0,0 +1,85 @@ +/* SPDX-License-Identifier: MIT */ +/****************************************************************************** + * callback.h + * + * Register guest OS callbacks with Xen. + * + * Copyright (c) 2006, Ian Campbell + */ + +#ifndef __XEN_PUBLIC_CALLBACK_H__ +#define __XEN_PUBLIC_CALLBACK_H__ + +#include + +/* + * Prototype for this hypercall is: + * long callback_op(int cmd, void *extra_args) + * @cmd == CALLBACKOP_??? (callback operation). + * @extra_args == Operation-specific extra arguments (NULL if none). + */ + +/* x86: Callback for event delivery. */ +#define CALLBACKTYPE_event 0 + +/* x86: Failsafe callback when guest state cannot be restored by Xen. */ +#define CALLBACKTYPE_failsafe 1 + +/* x86/64 hypervisor: Syscall by 64-bit guest app ('64-on-64-on-64'). */ +#define CALLBACKTYPE_syscall 2 + +/* + * x86/32 hypervisor: Only available on x86/32 when supervisor_mode_kernel + * feature is enabled. Do not use this callback type in new code. + */ +#define CALLBACKTYPE_sysenter_deprecated 3 + +/* x86: Callback for NMI delivery. */ +#define CALLBACKTYPE_nmi 4 + +/* + * x86: sysenter is only available as follows: + * - 32-bit hypervisor: with the supervisor_mode_kernel feature enabled + * - 64-bit hypervisor: 32-bit guest applications on Intel CPUs + * ('32-on-32-on-64', '32-on-64-on-64') + * [nb. also 64-bit guest applications on Intel CPUs + * ('64-on-64-on-64'), but syscall is preferred] + */ +#define CALLBACKTYPE_sysenter 5 + +/* + * x86/64 hypervisor: Syscall by 32-bit guest app on AMD CPUs + * ('32-on-32-on-64', '32-on-64-on-64') + */ +#define CALLBACKTYPE_syscall32 7 + +/* + * Disable event deliver during callback? This flag is ignored for event and + * NMI callbacks: event delivery is unconditionally disabled. + */ +#define _CALLBACKF_mask_events 0 +#define CALLBACKF_mask_events (1U << _CALLBACKF_mask_events) + +/* + * Register a callback. + */ +#define CALLBACKOP_register 0 +struct callback_register { + uint16_t type; + uint16_t flags; + xen_callback_t address; +}; + +/* + * Unregister a callback. + * + * Not all callbacks can be unregistered. -EINVAL will be returned if + * you attempt to unregister such a callback. + */ +#define CALLBACKOP_unregister 1 +struct callback_unregister { + uint16_t type; + uint16_t _unused; +}; + +#endif /* __XEN_PUBLIC_CALLBACK_H__ */ -- cgit v1.3.1