linux-kernel - [PATCH] PMCR_EL0.N is RAZ/WI. At least a build failes in Ubuntu 22.04 LTS. Remove the set function.

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-Id: <20250912-selftest-fix3-v1-1-256710a5ae5b@linux.dev>
Date: Fri, 12 Sep 2025 17:27:40 +0900
From: Itaru Kitayama <itaru.kitayama@...ux.dev>
To: Marc Zyngier <maz@...nel.org>, Oliver Upton <oliver.upton@...ux.dev>, 
 Joey Gouly <joey.gouly@....com>, Suzuki K Poulose <suzuki.poulose@....com>, 
 Zenghui Yu <yuzenghui@...wei.com>, Paolo Bonzini <pbonzini@...hat.com>, 
 Shuah Khan <shuah@...nel.org>
Cc: linux-arm-kernel@...ts.infradead.org, kvmarm@...ts.linux.dev, 
 kvm@...r.kernel.org, linux-kselftest@...r.kernel.org, 
 linux-kernel@...r.kernel.org, Itaru Kitayama <itaru.kitayama@...itsu.com>
Subject: [PATCH] PMCR_EL0.N is RAZ/WI. At least a build failes in Ubuntu
 22.04 LTS. Remove the set function.

Signed-off-by: Itaru Kitayama <itaru.kitayama@...itsu.com>
---
Seen a build failure with old Ubuntu 22.04 LTS, while the latest release
has no build issue, a write to the bit fields is RAZ/WI, remove the
function.
---
 tools/testing/selftests/kvm/arm64/vpmu_counter_access.c | 6 ------
 1 file changed, 6 deletions(-)

diff --git a/tools/testing/selftests/kvm/arm64/vpmu_counter_access.c b/tools/testing/selftests/kvm/arm64/vpmu_counter_access.c
index f16b3b27e32ed7ca57481f27d689d47783aa0345..56214a4430be90b3e1d840f2719b22dd44f0b49b 100644
--- a/tools/testing/selftests/kvm/arm64/vpmu_counter_access.c
+++ b/tools/testing/selftests/kvm/arm64/vpmu_counter_access.c
@@ -45,11 +45,6 @@ static uint64_t get_pmcr_n(uint64_t pmcr)
 	return FIELD_GET(ARMV8_PMU_PMCR_N, pmcr);
 }

-static void set_pmcr_n(uint64_t *pmcr, uint64_t pmcr_n)
-{
-	u64p_replace_bits((__u64 *) pmcr, pmcr_n, ARMV8_PMU_PMCR_N);
-}
-
 static uint64_t get_counters_mask(uint64_t n)
 {
 	uint64_t mask = BIT(ARMV8_PMU_CYCLE_IDX);
@@ -490,7 +485,6 @@ static void test_create_vpmu_vm_with_pmcr_n(uint64_t pmcr_n, bool expect_fail)
 	 * Setting a larger value of PMCR.N should not modify the field, and
 	 * return a success.
 	 */
-	set_pmcr_n(&pmcr, pmcr_n);
 	vcpu_set_reg(vcpu, KVM_ARM64_SYS_REG(SYS_PMCR_EL0), pmcr);
 	pmcr = vcpu_get_reg(vcpu, KVM_ARM64_SYS_REG(SYS_PMCR_EL0));

---
base-commit: aae5a9834b388860844b294c70c8770dd26e528c
change-id: 20250912-selftest-fix3-27f285e79d82

Best regards,
-- 
Itaru Kitayama <itaru.kitayama@...ux.dev>