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/regulator/event.c | 91 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 91 insertions(+) create mode 100644 drivers/regulator/event.c (limited to 'drivers/regulator/event.c') diff --git a/drivers/regulator/event.c b/drivers/regulator/event.c new file mode 100644 index 000000000..ea3bd4954 --- /dev/null +++ b/drivers/regulator/event.c @@ -0,0 +1,91 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Regulator event over netlink + * + * Author: Naresh Solanki + */ + +#include +#include +#include +#include + +#include "regnl.h" + +static atomic_t reg_event_seqnum = ATOMIC_INIT(0); + +static const struct genl_multicast_group reg_event_mcgrps[] = { + { .name = REG_GENL_MCAST_GROUP_NAME, }, +}; + +static struct genl_family reg_event_genl_family __ro_after_init = { + .module = THIS_MODULE, + .name = REG_GENL_FAMILY_NAME, + .version = REG_GENL_VERSION, + .maxattr = REG_GENL_ATTR_MAX, + .mcgrps = reg_event_mcgrps, + .n_mcgrps = ARRAY_SIZE(reg_event_mcgrps), +}; + +int reg_generate_netlink_event(const char *reg_name, u64 event) +{ + struct sk_buff *skb; + struct nlattr *attr; + struct reg_genl_event *edata; + void *msg_header; + int size; + + /* allocate memory */ + size = nla_total_size(sizeof(struct reg_genl_event)) + + nla_total_size(0); + + skb = genlmsg_new(size, GFP_ATOMIC); + if (!skb) + return -ENOMEM; + + /* add the genetlink message header */ + msg_header = genlmsg_put(skb, 0, atomic_inc_return(®_event_seqnum), + ®_event_genl_family, 0, REG_GENL_CMD_EVENT); + if (!msg_header) { + nlmsg_free(skb); + return -ENOMEM; + } + + /* fill the data */ + attr = nla_reserve(skb, REG_GENL_ATTR_EVENT, sizeof(struct reg_genl_event)); + if (!attr) { + nlmsg_free(skb); + return -EINVAL; + } + + edata = nla_data(attr); + memset(edata, 0, sizeof(struct reg_genl_event)); + + strscpy(edata->reg_name, reg_name, sizeof(edata->reg_name)); + edata->event = event; + + /* send multicast genetlink message */ + genlmsg_end(skb, msg_header); + size = genlmsg_multicast(®_event_genl_family, skb, 0, 0, GFP_ATOMIC); + + return size; +} + +static int __init reg_event_genetlink_init(void) +{ + return genl_register_family(®_event_genl_family); +} + +static int __init reg_event_init(void) +{ + int error; + + /* create genetlink for acpi event */ + error = reg_event_genetlink_init(); + if (error) + pr_warn("Failed to create genetlink family for reg event\n"); + + return 0; +} + +fs_initcall(reg_event_init); -- cgit v1.3.1