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 --- drivers/misc/pvpanic/Kconfig | 27 +++++++++++++++++++++++++++ 1 file changed, 27 insertions(+) create mode 100644 drivers/misc/pvpanic/Kconfig (limited to 'drivers/misc/pvpanic/Kconfig') diff --git a/drivers/misc/pvpanic/Kconfig b/drivers/misc/pvpanic/Kconfig new file mode 100644 index 000000000..12d40a21f --- /dev/null +++ b/drivers/misc/pvpanic/Kconfig @@ -0,0 +1,27 @@ +# SPDX-License-Identifier: GPL-2.0+ +# +# Pvpanic Kconfig +# +# Copyright (C) 2021 Oracle. +# + +config PVPANIC + bool "pvpanic device support" + help + This option allows to select a specific pvpanic device driver. + pvpanic is a paravirtualized device provided by QEMU; it lets + a virtual machine (guest) communicate panic events to the host. + +config PVPANIC_MMIO + tristate "pvpanic MMIO device support" + depends on HAS_IOMEM && (ACPI || OF) && PVPANIC + help + This driver provides support for the MMIO pvpanic device. + +config PVPANIC_PCI + tristate "pvpanic PCI device support" + depends on PCI && PVPANIC + help + This driver provides support for the PCI pvpanic device. + pvpanic is a paravirtualized device provided by QEMU which + forwards the panic events from the guest to the host. -- cgit v1.3.1