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 --- lib/kunit/debugfs.h | 30 ++++++++++++++++++++++++++++++ 1 file changed, 30 insertions(+) create mode 100644 lib/kunit/debugfs.h (limited to 'lib/kunit/debugfs.h') diff --git a/lib/kunit/debugfs.h b/lib/kunit/debugfs.h new file mode 100644 index 000000000..dcc7d7556 --- /dev/null +++ b/lib/kunit/debugfs.h @@ -0,0 +1,30 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright (C) 2020, Oracle and/or its affiliates. + */ + +#ifndef _KUNIT_DEBUGFS_H +#define _KUNIT_DEBUGFS_H + +#include + +#ifdef CONFIG_KUNIT_DEBUGFS + +void kunit_debugfs_create_suite(struct kunit_suite *suite); +void kunit_debugfs_destroy_suite(struct kunit_suite *suite); +void kunit_debugfs_init(void); +void kunit_debugfs_cleanup(void); + +#else + +static inline void kunit_debugfs_create_suite(struct kunit_suite *suite) { } + +static inline void kunit_debugfs_destroy_suite(struct kunit_suite *suite) { } + +static inline void kunit_debugfs_init(void) { } + +static inline void kunit_debugfs_cleanup(void) { } + +#endif /* CONFIG_KUNIT_DEBUGFS */ + +#endif /* _KUNIT_DEBUGFS_H */ -- cgit v1.3.1