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/rtc/proc.c | 92 ++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 92 insertions(+) create mode 100644 drivers/rtc/proc.c (limited to 'drivers/rtc/proc.c') diff --git a/drivers/rtc/proc.c b/drivers/rtc/proc.c new file mode 100644 index 000000000..cbcdbb19d --- /dev/null +++ b/drivers/rtc/proc.c @@ -0,0 +1,92 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * RTC subsystem, proc interface + * + * Copyright (C) 2005-06 Tower Technologies + * Author: Alessandro Zummo + * + * based on arch/arm/common/rtctime.c + */ + +#include +#include +#include +#include + +#include "rtc-core.h" + +#define NAME_SIZE 10 + +#if defined(CONFIG_RTC_HCTOSYS_DEVICE) +static bool is_rtc_hctosys(struct rtc_device *rtc) +{ + int size; + char name[NAME_SIZE]; + + size = snprintf(name, NAME_SIZE, "rtc%d", rtc->id); + if (size >= NAME_SIZE) + return false; + + return !strncmp(name, CONFIG_RTC_HCTOSYS_DEVICE, NAME_SIZE); +} +#else +static bool is_rtc_hctosys(struct rtc_device *rtc) +{ + return (rtc->id == 0); +} +#endif + +static int rtc_proc_show(struct seq_file *seq, void *offset) +{ + int err; + struct rtc_device *rtc = seq->private; + const struct rtc_class_ops *ops = rtc->ops; + struct rtc_wkalrm alrm; + struct rtc_time tm; + + err = rtc_read_time(rtc, &tm); + if (err == 0) { + seq_printf(seq, + "rtc_time\t: %ptRt\n" + "rtc_date\t: %ptRd\n", + &tm, &tm); + } + + err = rtc_read_alarm(rtc, &alrm); + if (err == 0) { + seq_printf(seq, "alrm_time\t: %ptRt\n", &alrm.time); + seq_printf(seq, "alrm_date\t: %ptRd\n", &alrm.time); + seq_printf(seq, "alarm_IRQ\t: %s\n", + alrm.enabled ? "yes" : "no"); + seq_printf(seq, "alrm_pending\t: %s\n", + alrm.pending ? "yes" : "no"); + seq_printf(seq, "update IRQ enabled\t: %s\n", + (rtc->uie_rtctimer.enabled) ? "yes" : "no"); + seq_printf(seq, "periodic IRQ enabled\t: %s\n", + (rtc->pie_enabled) ? "yes" : "no"); + seq_printf(seq, "periodic IRQ frequency\t: %d\n", + rtc->irq_freq); + seq_printf(seq, "max user IRQ frequency\t: %d\n", + rtc->max_user_freq); + } + + seq_printf(seq, "24hr\t\t: yes\n"); + + if (ops->proc) + ops->proc(rtc->dev.parent, seq); + + return 0; +} + +void rtc_proc_add_device(struct rtc_device *rtc) +{ + if (is_rtc_hctosys(rtc)) + proc_create_single_data("driver/rtc", 0, NULL, rtc_proc_show, + rtc); +} + +void rtc_proc_del_device(struct rtc_device *rtc) +{ + if (is_rtc_hctosys(rtc)) + remove_proc_entry("driver/rtc", NULL); +} -- cgit v1.3.1