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, 51 insertions, 0 deletions

diff --git a/include/sound/util_mem.h b/include/sound/util_mem.h
new file mode 100644
index 000000000..01310e089
--- /dev/null
+++ b/include/sound/util_mem.h
@@ -0,0 +1,51 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+#ifndef __SOUND_UTIL_MEM_H
+#define __SOUND_UTIL_MEM_H
+
+#include <linux/mutex.h>
+/*
+ *  Copyright (C) 2000 Takashi Iwai <tiwai@suse.de>
+ *
+ *  Generic memory management routines for soundcard memory allocation
+ */
+
+/*
+ * memory block
+ */
+struct snd_util_memblk {
+	unsigned int size;		/* size of this block */
+	unsigned int offset;		/* zero-offset of this block */
+	struct list_head list;		/* link */
+};
+
+#define snd_util_memblk_argptr(blk)	(void*)((char*)(blk) + sizeof(struct snd_util_memblk))
+
+/*
+ * memory management information
+ */
+struct snd_util_memhdr {
+	unsigned int size;		/* size of whole data */
+	struct list_head block;		/* block linked-list header */
+	int nblocks;			/* # of allocated blocks */
+	unsigned int used;		/* used memory size */
+	int block_extra_size;		/* extra data size of chunk */
+	struct mutex block_mutex;	/* lock */
+};
+
+/*
+ * prototypes
+ */
+struct snd_util_memhdr *snd_util_memhdr_new(int memsize);
+void snd_util_memhdr_free(struct snd_util_memhdr *hdr);
+struct snd_util_memblk *snd_util_mem_alloc(struct snd_util_memhdr *hdr, int size);
+int snd_util_mem_free(struct snd_util_memhdr *hdr, struct snd_util_memblk *blk);
+int snd_util_mem_avail(struct snd_util_memhdr *hdr);
+
+/* functions without mutex */
+struct snd_util_memblk *__snd_util_mem_alloc(struct snd_util_memhdr *hdr, int size);
+void __snd_util_mem_free(struct snd_util_memhdr *hdr, struct snd_util_memblk *blk);
+struct snd_util_memblk *__snd_util_memblk_new(struct snd_util_memhdr *hdr,
+					      unsigned int units,
+					      struct list_head *prev);
+
+#endif /* __SOUND_UTIL_MEM_H */