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, 19 insertions, 0 deletions

diff --git a/include/net/xdp_priv.h b/include/net/xdp_priv.h
new file mode 100644
index 000000000..c9df68d5f
--- /dev/null
+++ b/include/net/xdp_priv.h
@@ -0,0 +1,19 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __LINUX_NET_XDP_PRIV_H__
+#define __LINUX_NET_XDP_PRIV_H__
+
+#include <linux/rhashtable.h>
+#include <net/xdp.h>
+
+/* Private to net/core/xdp.c, but used by trace/events/xdp.h */
+struct xdp_mem_allocator {
+	struct xdp_mem_info mem;
+	union {
+		void *allocator;
+		struct page_pool *page_pool;
+	};
+	struct rhash_head node;
+	struct rcu_head rcu;
+};
+
+#endif /* __LINUX_NET_XDP_PRIV_H__ */