diff options
| author | thomas knych <thomaswk@google.com> | 2014-01-09 13:14:23 -0800 |
|---|---|---|
| committer | Paolo Bonzini <pbonzini@redhat.com> | 2014-01-15 12:58:41 +0100 |
| commit | 94ccff133820552a859c0fb95e33a539e0b90a75 (patch) | |
| tree | 0fbf9538748867da53e5b72e6235f94784c51c0c | |
| parent | 2ba82852894c762299b7d05e9a2be184116b80f0 (diff) | |
KVM: Retry KVM_CREATE_VM on EINTR
Upstreaming this change from Android (https://android-review.googlesource.com/54211).
On heavily loaded machines with many VM instances we see KVM_CREATE_VM
failing with EINTR on this path:
kvm_dev_ioctl_create_vm -> kvm_create_vm -> kvm_init_mmu_notifier -> mmu_notifier_register -> do_mmu_notifier_register -> mm_take_all_locks
which checks if any signals have been raised while it was attaining locks
and returns EINTR. Retrying the system call greatly improves reliability.
Cc: qemu-stable@nongnu.org
Signed-off-by: thomas knych <thomaswk@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
| -rw-r--r-- | kvm-all.c | 12 |
1 files changed, 9 insertions, 3 deletions
@@ -1442,16 +1442,22 @@ int kvm_init(void) nc++; } - s->vmfd = kvm_ioctl(s, KVM_CREATE_VM, 0); - if (s->vmfd < 0) { + do { + ret = kvm_ioctl(s, KVM_CREATE_VM, 0); + } while (ret == -EINTR); + + if (ret < 0) { + fprintf(stderr, "ioctl(KVM_CREATE_VM) failed: %d %s\n", -s->vmfd, + strerror(-ret)); + #ifdef TARGET_S390X fprintf(stderr, "Please add the 'switch_amode' kernel parameter to " "your host kernel command line\n"); #endif - ret = s->vmfd; goto err; } + s->vmfd = ret; missing_cap = kvm_check_extension_list(s, kvm_required_capabilites); if (!missing_cap) { missing_cap = |