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, 49 insertions, 0 deletions

diff --git a/include/crypto/aes-ecb.h b/include/crypto/aes-ecb.h
new file mode 100644
index 000000000..8cac1f879
--- /dev/null
+++ b/include/crypto/aes-ecb.h
@@ -0,0 +1,49 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * AES-ECB unauthenticated encryption and decryption
+ *
+ * Copyright 2026 Google LLC
+ */
+#ifndef _CRYPTO_AES_ECB_H
+#define _CRYPTO_AES_ECB_H
+
+#include <crypto/aes.h>
+
+/**
+ * aes_ecb_encrypt() - Encrypt data using AES-ECB
+ * @dst: The destination buffer.  Can be in-place or out-of-place.  For other
+ *	 overlaps the behavior is unspecified.
+ * @src: The source data
+ * @len: Number of bytes to encrypt.  Must be a multiple of AES_BLOCK_SIZE.
+ * @key: The key, already prepared using aes_preparekey() or aes_prepareenckey()
+ *
+ * ECB mode is insecure by itself.  This function exists only for compatibility
+ * with legacy protocols and for internal use by other modes.
+ *
+ * This supports incremental encryption, but the length of each chunk must be a
+ * multiple of AES_BLOCK_SIZE.
+ *
+ * Context: Any context.
+ */
+void aes_ecb_encrypt(u8 *dst, const u8 *src, size_t len, aes_encrypt_arg key);
+
+/**
+ * aes_ecb_decrypt() - Decrypt data using AES-ECB
+ * @dst: The destination buffer.  Can be in-place or out-of-place.  For other
+ *	 overlaps the behavior is unspecified.
+ * @src: The source data
+ * @len: Number of bytes to decrypt.  Must be a multiple of AES_BLOCK_SIZE.
+ * @key: The key, already prepared using aes_preparekey()
+ *
+ * ECB mode is insecure by itself.  This function exists only for compatibility
+ * with legacy protocols and for internal use by other modes.
+ *
+ * This supports incremental decryption, but the length of each chunk must be a
+ * multiple of AES_BLOCK_SIZE.
+ *
+ * Context: Any context.
+ */
+void aes_ecb_decrypt(u8 *dst, const u8 *src, size_t len,
+		     const struct aes_key *key);
+
+#endif /* _CRYPTO_AES_ECB_H */