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/base/regmap/regmap-slimbus.c | 70 ++++++++++++++++++++++++++++++++++++ 1 file changed, 70 insertions(+) create mode 100644 drivers/base/regmap/regmap-slimbus.c (limited to 'drivers/base/regmap/regmap-slimbus.c') diff --git a/drivers/base/regmap/regmap-slimbus.c b/drivers/base/regmap/regmap-slimbus.c new file mode 100644 index 000000000..e523fae73 --- /dev/null +++ b/drivers/base/regmap/regmap-slimbus.c @@ -0,0 +1,70 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright (c) 2017, Linaro Ltd. + +#include +#include +#include + +#include "internal.h" + +static int regmap_slimbus_write(void *context, const void *data, size_t count) +{ + struct slim_device *sdev = context; + + return slim_write(sdev, *(u16 *)data, count - 2, (u8 *)data + 2); +} + +static int regmap_slimbus_read(void *context, const void *reg, size_t reg_size, + void *val, size_t val_size) +{ + struct slim_device *sdev = context; + + return slim_read(sdev, *(u16 *)reg, val_size, val); +} + +static const struct regmap_bus regmap_slimbus_bus = { + .write = regmap_slimbus_write, + .read = regmap_slimbus_read, + .reg_format_endian_default = REGMAP_ENDIAN_LITTLE, + .val_format_endian_default = REGMAP_ENDIAN_LITTLE, +}; + +static const struct regmap_bus *regmap_get_slimbus(struct slim_device *slim, + const struct regmap_config *config) +{ + if (config->val_bits == 8 && config->reg_bits == 16) + return ®map_slimbus_bus; + + return ERR_PTR(-ENOTSUPP); +} + +struct regmap *__regmap_init_slimbus(struct slim_device *slimbus, + const struct regmap_config *config, + struct lock_class_key *lock_key, + const char *lock_name) +{ + const struct regmap_bus *bus = regmap_get_slimbus(slimbus, config); + + if (IS_ERR(bus)) + return ERR_CAST(bus); + + return __regmap_init(&slimbus->dev, bus, slimbus, config, lock_key, lock_name); +} +EXPORT_SYMBOL_GPL(__regmap_init_slimbus); + +struct regmap *__devm_regmap_init_slimbus(struct slim_device *slimbus, + const struct regmap_config *config, + struct lock_class_key *lock_key, + const char *lock_name) +{ + const struct regmap_bus *bus = regmap_get_slimbus(slimbus, config); + + if (IS_ERR(bus)) + return ERR_CAST(bus); + + return __devm_regmap_init(&slimbus->dev, bus, slimbus, config, lock_key, lock_name); +} +EXPORT_SYMBOL_GPL(__devm_regmap_init_slimbus); + +MODULE_DESCRIPTION("Register map access API - SLIMbus support"); +MODULE_LICENSE("GPL v2"); -- cgit v1.3.1