Re: [PATCH v6 07/11] KVM: arm64: PMU: Allow userspace to limit PMCR_EL0.N for the guest
From: kernel test robot
Date: Thu Sep 28 2023 - 19:09:18 EST
Hi Raghavendra,
kernel test robot noticed the following build errors:
[auto build test ERROR on 6465e260f48790807eef06b583b38ca9789b6072]
url: https://github.com/intel-lab-lkp/linux/commits/Raghavendra-Rao-Ananta/KVM-arm64-PMU-Introduce-helpers-to-set-the-guest-s-PMU/20230927-095821
base: 6465e260f48790807eef06b583b38ca9789b6072
patch link: https://lore.kernel.org/r/20230926234008.2348607-8-rananta%40google.com
patch subject: [PATCH v6 07/11] KVM: arm64: PMU: Allow userspace to limit PMCR_EL0.N for the guest
config: arm64-randconfig-003-20230928 (https://download.01.org/0day-ci/archive/20230929/202309290607.Qgg05wKw-lkp@xxxxxxxxx/config)
compiler: aarch64-linux-gcc (GCC) 13.2.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20230929/202309290607.Qgg05wKw-lkp@xxxxxxxxx/reproduce)
If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@xxxxxxxxx>
| Closes: https://lore.kernel.org/oe-kbuild-all/202309290607.Qgg05wKw-lkp@xxxxxxxxx/
All errors (new ones prefixed by >>):
arch/arm64/kvm/sys_regs.c: In function 'set_pmcr':
>> arch/arm64/kvm/sys_regs.c:1110:52: error: invalid use of undefined type 'struct arm_pmu'
1110 | u8 pmcr_n_limit = kvm->arch.arm_pmu->num_events - 1;
| ^~
arch/arm64/kvm/sys_regs.c: At top level:
arch/arm64/kvm/sys_regs.c:2207:66: warning: initialized field overwritten [-Woverride-init]
2207 | { PMU_SYS_REG(PMCR_EL0), .access = access_pmcr, .reset = reset_pmcr,
| ^~~~~~~~~~
arch/arm64/kvm/sys_regs.c:2207:66: note: (near initialization for 'sys_reg_descs[233].reset')
In file included from include/uapi/linux/posix_types.h:5,
from include/uapi/linux/types.h:14,
from include/linux/types.h:6,
from include/linux/kasan-checks.h:5,
from include/asm-generic/rwonce.h:26,
from arch/arm64/include/asm/rwonce.h:71,
from include/linux/compiler.h:246,
from include/linux/build_bug.h:5,
from include/linux/bitfield.h:10,
from arch/arm64/kvm/sys_regs.c:12:
include/linux/stddef.h:8:14: warning: initialized field overwritten [-Woverride-init]
8 | #define NULL ((void *)0)
| ^
arch/arm64/kvm/sys_regs.c:2221:46: note: in expansion of macro 'NULL'
2221 | .access = access_pmswinc, .reset = NULL },
| ^~~~
include/linux/stddef.h:8:14: note: (near initialization for 'sys_reg_descs[237].reset')
8 | #define NULL ((void *)0)
| ^
arch/arm64/kvm/sys_regs.c:2221:46: note: in expansion of macro 'NULL'
2221 | .access = access_pmswinc, .reset = NULL },
| ^~~~
arch/arm64/kvm/sys_regs.c:2223:45: warning: initialized field overwritten [-Woverride-init]
2223 | .access = access_pmselr, .reset = reset_pmselr, .reg = PMSELR_EL0 },
| ^~~~~~~~~~~~
arch/arm64/kvm/sys_regs.c:2223:45: note: (near initialization for 'sys_reg_descs[238].reset')
include/linux/stddef.h:8:14: warning: initialized field overwritten [-Woverride-init]
8 | #define NULL ((void *)0)
| ^
arch/arm64/kvm/sys_regs.c:2225:45: note: in expansion of macro 'NULL'
2225 | .access = access_pmceid, .reset = NULL },
| ^~~~
include/linux/stddef.h:8:14: note: (near initialization for 'sys_reg_descs[239].reset')
8 | #define NULL ((void *)0)
| ^
arch/arm64/kvm/sys_regs.c:2225:45: note: in expansion of macro 'NULL'
2225 | .access = access_pmceid, .reset = NULL },
| ^~~~
include/linux/stddef.h:8:14: warning: initialized field overwritten [-Woverride-init]
8 | #define NULL ((void *)0)
| ^
arch/arm64/kvm/sys_regs.c:2227:45: note: in expansion of macro 'NULL'
2227 | .access = access_pmceid, .reset = NULL },
| ^~~~
include/linux/stddef.h:8:14: note: (near initialization for 'sys_reg_descs[240].reset')
8 | #define NULL ((void *)0)
| ^
arch/arm64/kvm/sys_regs.c:2227:45: note: in expansion of macro 'NULL'
2227 | .access = access_pmceid, .reset = NULL },
| ^~~~
arch/arm64/kvm/sys_regs.c:2229:49: warning: initialized field overwritten [-Woverride-init]
2229 | .access = access_pmu_evcntr, .reset = reset_unknown,
| ^~~~~~~~~~~~~
arch/arm64/kvm/sys_regs.c:2229:49: note: (near initialization for 'sys_reg_descs[241].reset')
include/linux/stddef.h:8:14: warning: initialized field overwritten [-Woverride-init]
8 | #define NULL ((void *)0)
| ^
arch/arm64/kvm/sys_regs.c:2232:50: note: in expansion of macro 'NULL'
2232 | .access = access_pmu_evtyper, .reset = NULL },
| ^~~~
include/linux/stddef.h:8:14: note: (near initialization for 'sys_reg_descs[242].reset')
8 | #define NULL ((void *)0)
| ^
arch/arm64/kvm/sys_regs.c:2232:50: note: in expansion of macro 'NULL'
2232 | .access = access_pmu_evtyper, .reset = NULL },
| ^~~~
include/linux/stddef.h:8:14: warning: initialized field overwritten [-Woverride-init]
8 | #define NULL ((void *)0)
| ^
arch/arm64/kvm/sys_regs.c:2234:49: note: in expansion of macro 'NULL'
2234 | .access = access_pmu_evcntr, .reset = NULL },
| ^~~~
include/linux/stddef.h:8:14: note: (near initialization for 'sys_reg_descs[243].reset')
8 | #define NULL ((void *)0)
| ^
arch/arm64/kvm/sys_regs.c:2234:49: note: in expansion of macro 'NULL'
2234 | .access = access_pmu_evcntr, .reset = NULL },
| ^~~~
arch/arm64/kvm/sys_regs.c:1162:20: warning: initialized field overwritten [-Woverride-init]
1162 | .reset = reset_pmevcntr, .get_user = get_pmu_evcntr, \
| ^~~~~~~~~~~~~~
arch/arm64/kvm/sys_regs.c:2330:9: note: in expansion of macro 'PMU_PMEVCNTR_EL0'
2330 | PMU_PMEVCNTR_EL0(0),
| ^~~~~~~~~~~~~~~~
arch/arm64/kvm/sys_regs.c:1162:20: note: (near initialization for 'sys_reg_descs[327].reset')
1162 | .reset = reset_pmevcntr, .get_user = get_pmu_evcntr, \
| ^~~~~~~~~~~~~~
arch/arm64/kvm/sys_regs.c:2330:9: note: in expansion of macro 'PMU_PMEVCNTR_EL0'
2330 | PMU_PMEVCNTR_EL0(0),
| ^~~~~~~~~~~~~~~~
arch/arm64/kvm/sys_regs.c:1162:20: warning: initialized field overwritten [-Woverride-init]
1162 | .reset = reset_pmevcntr, .get_user = get_pmu_evcntr, \
| ^~~~~~~~~~~~~~
vim +1110 arch/arm64/kvm/sys_regs.c
1090
1091 static int set_pmcr(struct kvm_vcpu *vcpu, const struct sys_reg_desc *r,
1092 u64 val)
1093 {
1094 struct kvm *kvm = vcpu->kvm;
1095 u64 new_n, mutable_mask;
1096
1097 mutex_lock(&kvm->arch.config_lock);
1098
1099 /*
1100 * Make PMCR immutable once the VM has started running, but do
1101 * not return an error (-EBUSY) to meet the existing expectations.
1102 */
1103 if (kvm_vm_has_ran_once(vcpu->kvm)) {
1104 mutex_unlock(&kvm->arch.config_lock);
1105 return 0;
1106 }
1107
1108 new_n = (val >> ARMV8_PMU_PMCR_N_SHIFT) & ARMV8_PMU_PMCR_N_MASK;
1109 if (new_n != kvm->arch.pmcr_n) {
> 1110 u8 pmcr_n_limit = kvm->arch.arm_pmu->num_events - 1;
1111
1112 /*
1113 * The vCPU can't have more counters than the PMU hardware
1114 * implements. Ignore this error to maintain compatibility
1115 * with the existing KVM behavior.
1116 */
1117 if (new_n <= pmcr_n_limit)
1118 kvm->arch.pmcr_n = new_n;
1119 }
1120 mutex_unlock(&kvm->arch.config_lock);
1121
1122 /*
1123 * Ignore writes to RES0 bits, read only bits that are cleared on
1124 * vCPU reset, and writable bits that KVM doesn't support yet.
1125 * (i.e. only PMCR.N and bits [7:0] are mutable from userspace)
1126 * The LP bit is RES0 when FEAT_PMUv3p5 is not supported on the vCPU.
1127 * But, we leave the bit as it is here, as the vCPU's PMUver might
1128 * be changed later (NOTE: the bit will be cleared on first vCPU run
1129 * if necessary).
1130 */
1131 mutable_mask = (ARMV8_PMU_PMCR_MASK |
1132 (ARMV8_PMU_PMCR_N_MASK << ARMV8_PMU_PMCR_N_SHIFT));
1133 val &= mutable_mask;
1134 val |= (__vcpu_sys_reg(vcpu, r->reg) & ~mutable_mask);
1135
1136 /* The LC bit is RES1 when AArch32 is not supported */
1137 if (!kvm_supports_32bit_el0())
1138 val |= ARMV8_PMU_PMCR_LC;
1139
1140 __vcpu_sys_reg(vcpu, r->reg) = val;
1141 return 0;
1142 }
1143
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki