From 450a563924ae9437758bd468c5b7cee9468ce749 Mon Sep 17 00:00:00 2001 From: Oliver Upton Date: Tue, 19 Jul 2022 12:52:29 +0000 Subject: [PATCH 1/4] KVM: stats: Fix value for KVM_STATS_UNIT_MAX for boolean stats commit 1b870fa5573e ("kvm: stats: tell userspace which values are boolean") added a new stat unit (boolean) but failed to raise KVM_STATS_UNIT_MAX. Fix by pointing UNIT_MAX at the new max value of UNIT_BOOLEAN. Fixes: 1b870fa5573e ("kvm: stats: tell userspace which values are boolean") Reported-by: Janis Schoetterl-Glausch Signed-off-by: Oliver Upton Message-Id: <20220719125229.2934273-1-oupton@google.com> Signed-off-by: Paolo Bonzini --- Documentation/virt/kvm/api.rst | 2 +- include/uapi/linux/kvm.h | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) diff --git a/Documentation/virt/kvm/api.rst b/Documentation/virt/kvm/api.rst index 6e090fb96a0e..98a283930307 100644 --- a/Documentation/virt/kvm/api.rst +++ b/Documentation/virt/kvm/api.rst @@ -5658,7 +5658,7 @@ by a string of size ``name_size``. #define KVM_STATS_UNIT_SECONDS (0x2 << KVM_STATS_UNIT_SHIFT) #define KVM_STATS_UNIT_CYCLES (0x3 << KVM_STATS_UNIT_SHIFT) #define KVM_STATS_UNIT_BOOLEAN (0x4 << KVM_STATS_UNIT_SHIFT) - #define KVM_STATS_UNIT_MAX KVM_STATS_UNIT_CYCLES + #define KVM_STATS_UNIT_MAX KVM_STATS_UNIT_BOOLEAN #define KVM_STATS_BASE_SHIFT 8 #define KVM_STATS_BASE_MASK (0xF << KVM_STATS_BASE_SHIFT) diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h index 811897dadcae..860f867c50c0 100644 --- a/include/uapi/linux/kvm.h +++ b/include/uapi/linux/kvm.h @@ -2084,7 +2084,7 @@ struct kvm_stats_header { #define KVM_STATS_UNIT_SECONDS (0x2 << KVM_STATS_UNIT_SHIFT) #define KVM_STATS_UNIT_CYCLES (0x3 << KVM_STATS_UNIT_SHIFT) #define KVM_STATS_UNIT_BOOLEAN (0x4 << KVM_STATS_UNIT_SHIFT) -#define KVM_STATS_UNIT_MAX KVM_STATS_UNIT_CYCLES +#define KVM_STATS_UNIT_MAX KVM_STATS_UNIT_BOOLEAN #define KVM_STATS_BASE_SHIFT 8 #define KVM_STATS_BASE_MASK (0xF << KVM_STATS_BASE_SHIFT) From e923b0537d28e15c9d31ce8b38f810b325816903 Mon Sep 17 00:00:00 2001 From: Gavin Shan Date: Tue, 19 Jul 2022 10:08:30 +0800 Subject: [PATCH 2/4] KVM: selftests: Fix target thread to be migrated in rseq_test In rseq_test, there are two threads, which are vCPU thread and migration worker separately. Unfortunately, the test has the wrong PID passed to sched_setaffinity() in the migration worker. It forces migration on the migration worker because zeroed PID represents the calling thread, which is the migration worker itself. It means the vCPU thread is never enforced to migration and it can migrate at any time, which eventually leads to failure as the following logs show. host# uname -r 5.19.0-rc6-gavin+ host# # cat /proc/cpuinfo | grep processor | tail -n 1 processor : 223 host# pwd /home/gavin/sandbox/linux.main/tools/testing/selftests/kvm host# for i in `seq 1 100`; do \ echo "--------> $i"; ./rseq_test; done --------> 1 --------> 2 --------> 3 --------> 4 --------> 5 --------> 6 ==== Test Assertion Failure ==== rseq_test.c:265: rseq_cpu == cpu pid=3925 tid=3925 errno=4 - Interrupted system call 1 0x0000000000401963: main at rseq_test.c:265 (discriminator 2) 2 0x0000ffffb044affb: ?? ??:0 3 0x0000ffffb044b0c7: ?? ??:0 4 0x0000000000401a6f: _start at ??:? rseq CPU = 4, sched CPU = 27 Fix the issue by passing correct parameter, TID of the vCPU thread, to sched_setaffinity() in the migration worker. Fixes: 61e52f1630f5 ("KVM: selftests: Add a test for KVM_RUN+rseq to detect task migration bugs") Suggested-by: Sean Christopherson Signed-off-by: Gavin Shan Reviewed-by: Oliver Upton Message-Id: <20220719020830.3479482-1-gshan@redhat.com> Reviewed-by: Andrew Jones Signed-off-by: Paolo Bonzini --- tools/testing/selftests/kvm/rseq_test.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) diff --git a/tools/testing/selftests/kvm/rseq_test.c b/tools/testing/selftests/kvm/rseq_test.c index 4158da0da2bb..2237d1aac801 100644 --- a/tools/testing/selftests/kvm/rseq_test.c +++ b/tools/testing/selftests/kvm/rseq_test.c @@ -82,8 +82,9 @@ static int next_cpu(int cpu) return cpu; } -static void *migration_worker(void *ign) +static void *migration_worker(void *__rseq_tid) { + pid_t rseq_tid = (pid_t)(unsigned long)__rseq_tid; cpu_set_t allowed_mask; int r, i, cpu; @@ -106,7 +107,7 @@ static void *migration_worker(void *ign) * stable, i.e. while changing affinity is in-progress. */ smp_wmb(); - r = sched_setaffinity(0, sizeof(allowed_mask), &allowed_mask); + r = sched_setaffinity(rseq_tid, sizeof(allowed_mask), &allowed_mask); TEST_ASSERT(!r, "sched_setaffinity failed, errno = %d (%s)", errno, strerror(errno)); smp_wmb(); @@ -231,7 +232,8 @@ int main(int argc, char *argv[]) vm = vm_create_default(VCPU_ID, 0, guest_code); ucall_init(vm, NULL); - pthread_create(&migration_thread, NULL, migration_worker, 0); + pthread_create(&migration_thread, NULL, migration_worker, + (void *)(unsigned long)gettid()); for (i = 0; !done; i++) { vcpu_run(vm, VCPU_ID); From dc951e22a1a2a6a11b29648c3c8b191bc8f3e5df Mon Sep 17 00:00:00 2001 From: Paolo Bonzini Date: Tue, 19 Jul 2022 09:16:53 -0400 Subject: [PATCH 3/4] tools headers UAPI: Sync linux/kvm.h with the kernel sources Silence this perf build warning: Warning: Kernel ABI header at 'tools/include/uapi/linux/kvm.h' differs from latest version at 'include/uapi/linux/kvm.h' diff -u tools/include/uapi/linux/kvm.h include/uapi/linux/kvm.h Reported-by: Arnaldo Carvalho de Melo Cc: Adrian Hunter Cc: Ian Rogers Cc: Jiri Olsa Cc: Namhyung Kim Signed-off-by: Paolo Bonzini --- tools/include/uapi/linux/kvm.h | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/tools/include/uapi/linux/kvm.h b/tools/include/uapi/linux/kvm.h index 5088bd9f1922..860f867c50c0 100644 --- a/tools/include/uapi/linux/kvm.h +++ b/tools/include/uapi/linux/kvm.h @@ -2083,7 +2083,8 @@ struct kvm_stats_header { #define KVM_STATS_UNIT_BYTES (0x1 << KVM_STATS_UNIT_SHIFT) #define KVM_STATS_UNIT_SECONDS (0x2 << KVM_STATS_UNIT_SHIFT) #define KVM_STATS_UNIT_CYCLES (0x3 << KVM_STATS_UNIT_SHIFT) -#define KVM_STATS_UNIT_MAX KVM_STATS_UNIT_CYCLES +#define KVM_STATS_UNIT_BOOLEAN (0x4 << KVM_STATS_UNIT_SHIFT) +#define KVM_STATS_UNIT_MAX KVM_STATS_UNIT_BOOLEAN #define KVM_STATS_BASE_SHIFT 8 #define KVM_STATS_BASE_MASK (0xF << KVM_STATS_BASE_SHIFT) From cf5029d5dd7cb0aaa53250fa9e389abd231606b3 Mon Sep 17 00:00:00 2001 From: Aaron Lewis Date: Thu, 14 Jul 2022 16:13:15 +0000 Subject: [PATCH 4/4] KVM: x86: Protect the unused bits in MSR exiting flags The flags for KVM_CAP_X86_USER_SPACE_MSR and KVM_X86_SET_MSR_FILTER have no protection for their unused bits. Without protection, future development for these features will be difficult. Add the protection needed to make it possible to extend these features in the future. Signed-off-by: Aaron Lewis Message-Id: <20220714161314.1715227-1-aaronlewis@google.com> Signed-off-by: Paolo Bonzini --- arch/x86/kvm/x86.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 143e37298d8a..e5fa335a4ea7 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -6029,6 +6029,11 @@ split_irqchip_unlock: r = 0; break; case KVM_CAP_X86_USER_SPACE_MSR: + r = -EINVAL; + if (cap->args[0] & ~(KVM_MSR_EXIT_REASON_INVAL | + KVM_MSR_EXIT_REASON_UNKNOWN | + KVM_MSR_EXIT_REASON_FILTER)) + break; kvm->arch.user_space_msr_mask = cap->args[0]; r = 0; break; @@ -6183,6 +6188,9 @@ static int kvm_vm_ioctl_set_msr_filter(struct kvm *kvm, void __user *argp) if (copy_from_user(&filter, user_msr_filter, sizeof(filter))) return -EFAULT; + if (filter.flags & ~KVM_MSR_FILTER_DEFAULT_DENY) + return -EINVAL; + for (i = 0; i < ARRAY_SIZE(filter.ranges); i++) empty &= !filter.ranges[i].nmsrs;