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, 53 insertions, 0 deletions

diff --git a/scripts/checkdeclares.pl b/scripts/checkdeclares.pl
new file mode 100755
index 000000000..f6d551c84
--- /dev/null
+++ b/scripts/checkdeclares.pl
@@ -0,0 +1,53 @@
+#!/usr/bin/env perl
+# SPDX-License-Identifier: GPL-2.0
+#
+# checkdeclares: find struct declared more than once
+#
+# Copyright 2021 Wan Jiabing<wanjiabing@vivo.com>
+# Inspired by checkincludes.pl
+#
+# This script checks for duplicate struct declares.
+# Note that this will not take into consideration macros so
+# you should run this only if you know you do have real dups
+# and do not have them under #ifdef's.
+# You could also just review the results.
+
+use strict;
+
+sub usage {
+	print "Usage: checkdeclares.pl file1.h ...\n";
+	print "Warns of struct declaration duplicates\n";
+	exit 1;
+}
+
+if ($#ARGV < 0) {
+	usage();
+}
+
+my $dup_counter = 0;
+
+foreach my $file (@ARGV) {
+	open(my $f, '<', $file)
+	    or die "Cannot open $file: $!.\n";
+
+	my %declaredstructs = ();
+
+	while (<$f>) {
+		if (m/^\s*struct\s*(\w*);$/o) {
+			++$declaredstructs{$1};
+		}
+	}
+
+	close($f);
+
+	foreach my $structname (keys %declaredstructs) {
+		if ($declaredstructs{$structname} > 1) {
+			print "$file: struct $structname is declared more than once.\n";
+			++$dup_counter;
+		}
+	}
+}
+
+if ($dup_counter == 0) {
+	print "No duplicate struct declares found.\n";
+}