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/firmware/google/memconsole.h | 36 ++++++++++++++++++++++++++++++++++++ 1 file changed, 36 insertions(+) create mode 100644 drivers/firmware/google/memconsole.h (limited to 'drivers/firmware/google/memconsole.h') diff --git a/drivers/firmware/google/memconsole.h b/drivers/firmware/google/memconsole.h new file mode 100644 index 000000000..aaff2b72b --- /dev/null +++ b/drivers/firmware/google/memconsole.h @@ -0,0 +1,36 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * memconsole.h + * + * Internal headers of the memory based BIOS console. + * + * Copyright 2017 Google Inc. + */ + +#ifndef __FIRMWARE_GOOGLE_MEMCONSOLE_H +#define __FIRMWARE_GOOGLE_MEMCONSOLE_H + +#include + +/* + * memconsole_setup + * + * Initialize the memory console, passing the function to handle read accesses. + */ +void memconsole_setup(ssize_t (*read_func)(char *, loff_t, size_t)); + +/* + * memconsole_sysfs_init + * + * Update memory console length and create binary file + * for firmware object. + */ +int memconsole_sysfs_init(void); + +/* memconsole_exit + * + * Unmap the console buffer. + */ +void memconsole_exit(void); + +#endif /* __FIRMWARE_GOOGLE_MEMCONSOLE_H */ -- cgit v1.3.1