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, 67 insertions, 0 deletions

diff --git a/include/trace/events/icmp.h b/include/trace/events/icmp.h
new file mode 100644
index 000000000..09ae11509
--- /dev/null
+++ b/include/trace/events/icmp.h
@@ -0,0 +1,67 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM icmp
+
+#if !defined(_TRACE_ICMP_H) || defined(TRACE_HEADER_MULTI_READ)
+#define _TRACE_ICMP_H
+
+#include <linux/icmp.h>
+#include <linux/tracepoint.h>
+
+TRACE_EVENT(icmp_send,
+
+		TP_PROTO(const struct sk_buff *skb, int type, int code),
+
+		TP_ARGS(skb, type, code),
+
+		TP_STRUCT__entry(
+			__field(const void *, skbaddr)
+			__field(int, type)
+			__field(int, code)
+			__array(__u8, saddr, 4)
+			__array(__u8, daddr, 4)
+			__field(__u16, sport)
+			__field(__u16, dport)
+			__field(unsigned short, ulen)
+		),
+
+		TP_fast_assign(
+			struct iphdr *iph = ip_hdr(skb);
+			struct udphdr *uh = udp_hdr(skb);
+			int proto_4 = iph->protocol;
+			__be32 *p32;
+
+			__entry->skbaddr = skb;
+			__entry->type = type;
+			__entry->code = code;
+
+			if (proto_4 != IPPROTO_UDP || (u8 *)uh < skb->head ||
+				(u8 *)uh + sizeof(struct udphdr)
+				> skb_tail_pointer(skb)) {
+				__entry->sport = 0;
+				__entry->dport = 0;
+				__entry->ulen = 0;
+			} else {
+				__entry->sport = ntohs(uh->source);
+				__entry->dport = ntohs(uh->dest);
+				__entry->ulen = udp_get_len_short(uh);
+			}
+
+			p32 = (__be32 *) __entry->saddr;
+			*p32 = iph->saddr;
+
+			p32 = (__be32 *) __entry->daddr;
+			*p32 = iph->daddr;
+		),
+
+		TP_printk("icmp_send: type=%d, code=%d. From %pI4:%u to %pI4:%u ulen=%d skbaddr=%p",
+			__entry->type, __entry->code,
+			__entry->saddr, __entry->sport, __entry->daddr,
+			__entry->dport, __entry->ulen, __entry->skbaddr)
+);
+
+#endif /* _TRACE_ICMP_H */
+
+/* This part must be outside protection */
+#include <trace/define_trace.h>
+