arm64/boot: Disable trapping of PMZR_EL0 writes to EL2grafted

__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 <fuad.tabba@linux.dev>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Reviewed-by: Oliver Upton <oupton@kernel.org>
Signed-off-by: Will Deacon <will@kernel.org>

1 files changed, 57 insertions, 0 deletions

diff --git a/include/acpi/apei.h b/include/acpi/apei.h
new file mode 100644
index 000000000..dc60f7db5
--- /dev/null
+++ b/include/acpi/apei.h
@@ -0,0 +1,57 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * apei.h - ACPI Platform Error Interface
+ */
+
+#ifndef ACPI_APEI_H
+#define ACPI_APEI_H
+
+#include <linux/acpi.h>
+#include <linux/cper.h>
+#include <asm/ioctls.h>
+
+#define APEI_ERST_INVALID_RECORD_ID	0xffffffffffffffffULL
+
+#define APEI_ERST_CLEAR_RECORD		_IOW('E', 1, u64)
+#define APEI_ERST_GET_RECORD_COUNT	_IOR('E', 2, u32)
+
+#ifdef __KERNEL__
+
+enum hest_status {
+	HEST_ENABLED,
+	HEST_DISABLED,
+	HEST_NOT_FOUND,
+};
+
+extern int hest_disable;
+extern int erst_disable;
+#ifdef CONFIG_ACPI_APEI_GHES
+extern bool ghes_disable;
+void __init acpi_ghes_init(void);
+#else
+#define ghes_disable 1
+static inline void acpi_ghes_init(void) { }
+#endif
+
+#ifdef CONFIG_ACPI_APEI
+void __init acpi_hest_init(void);
+#else
+static inline void acpi_hest_init(void) { }
+#endif
+
+int erst_write(const struct cper_record_header *record);
+ssize_t erst_get_record_count(void);
+int erst_get_record_id_begin(int *pos);
+int erst_get_record_id_next(int *pos, u64 *record_id);
+void erst_get_record_id_end(void);
+ssize_t erst_read(u64 record_id, struct cper_record_header *record,
+		  size_t buflen);
+ssize_t erst_read_record(u64 record_id, struct cper_record_header *record,
+		size_t buflen, size_t recordlen, const guid_t *creatorid);
+int erst_clear(u64 record_id);
+
+int arch_apei_enable_cmcff(struct acpi_hest_header *hest_hdr, void *data);
+void arch_apei_report_mem_error(int sev, struct cper_sec_mem_err *mem_err);
+
+#endif
+#endif