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, 77 insertions, 0 deletions

diff --git a/include/crypto/aes-cbc.h b/include/crypto/aes-cbc.h
new file mode 100644
index 000000000..7bae34093
--- /dev/null
+++ b/include/crypto/aes-cbc.h
@@ -0,0 +1,77 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * AES-CBC and AES-CBC-CTS unauthenticated encryption and decryption
+ *
+ * Copyright 2026 Google LLC
+ */
+#ifndef _CRYPTO_AES_CBC_H
+#define _CRYPTO_AES_CBC_H
+
+#include <crypto/aes.h>
+
+/**
+ * aes_cbc_encrypt() - Encrypt data using AES-CBC
+ * @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.
+ * @iv: The initialization vector.  It is updated with the next value, i.e. the
+ *	last ciphertext block (or left unchanged if @len == 0).
+ * @key: The key, already prepared using aes_preparekey() or aes_prepareenckey()
+ *
+ * This supports incremental encryption.  The length of each chunk must be a
+ * multiple of AES_BLOCK_SIZE, and the updated @iv must be passed in each time.
+ *
+ * Context: Any context.
+ */
+void aes_cbc_encrypt(u8 *dst, const u8 *src, size_t len,
+		     u8 iv[at_least AES_BLOCK_SIZE], aes_encrypt_arg key);
+
+/**
+ * aes_cbc_decrypt() - Decrypt data using AES-CBC
+ * @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.
+ * @iv: The initialization vector.  It is updated with the next value, i.e. the
+ *	last ciphertext block (or left unchanged if @len == 0).
+ * @key: The key, already prepared using aes_preparekey()
+ *
+ * This supports incremental decryption.  The length of each chunk must be a
+ * multiple of AES_BLOCK_SIZE, and the updated @iv must be passed in each time.
+ *
+ * Context: Any context.
+ */
+void aes_cbc_decrypt(u8 *dst, const u8 *src, size_t len,
+		     u8 iv[at_least AES_BLOCK_SIZE], const struct aes_key *key);
+
+/**
+ * aes_cbc_cts_encrypt() - Encrypt data using AES-CBC-CTS (CS3 variant)
+ * @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, at least AES_BLOCK_SIZE
+ * @iv: The initialization vector, clobbered by this function
+ * @key: The key, already prepared using aes_preparekey() or aes_prepareenckey()
+ *
+ * Context: Any context.
+ */
+void aes_cbc_cts_encrypt(u8 *dst, const u8 *src, size_t len,
+			 u8 iv[at_least AES_BLOCK_SIZE], aes_encrypt_arg key);
+
+/**
+ * aes_cbc_cts_decrypt() - Decrypt data using AES-CBC-CTS (CS3 variant)
+ * @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, at least AES_BLOCK_SIZE
+ * @iv: The initialization vector, clobbered by this function
+ * @key: The key, already prepared using aes_preparekey()
+ *
+ * Context: Any context.
+ */
+void aes_cbc_cts_decrypt(u8 *dst, const u8 *src, size_t len,
+			 u8 iv[at_least AES_BLOCK_SIZE],
+			 const struct aes_key *key);
+
+#endif /* _CRYPTO_AES_CBC_H */