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, 12 insertions, 0 deletions

diff --git a/lib/math/Makefile b/lib/math/Makefile
new file mode 100644
index 000000000..9a3850d55
--- /dev/null
+++ b/lib/math/Makefile
@@ -0,0 +1,12 @@
+# SPDX-License-Identifier: GPL-2.0-only
+obj-y += div64.o gcd.o lcm.o int_log.o int_pow.o int_sqrt.o reciprocal_div.o
+
+obj-$(CONFIG_CORDIC)		+= cordic.o
+obj-$(CONFIG_POLYNOMIAL)	+= polynomial.o
+obj-$(CONFIG_PRIME_NUMBERS)	+= prime_numbers.o
+obj-$(CONFIG_RATIONAL)		+= rational.o
+
+obj-$(CONFIG_TEST_DIV64)	+= test_div64.o
+obj-$(CONFIG_TEST_MULDIV64)	+= test_mul_u64_u64_div_u64.o
+
+obj-y += tests/