From c2b823970192882fe033d0d9f919003747d3e26f Mon Sep 17 00:00:00 2001 From: Sean Christopherson Date: Tue, 16 Aug 2022 05:39:37 +0000 Subject: KVM: Move coalesced MMIO initialization (back) into kvm_create_vm() Invoke kvm_coalesced_mmio_init() from kvm_create_vm() now that allocating and initializing coalesced MMIO objects is separate from registering any associated devices. Moving coalesced MMIO cleans up the last oddity where KVM does VM creation/initialization after kvm_create_vm(), and more importantly after kvm_arch_post_init_vm() is called and the VM is added to the global vm_list, i.e. after the VM is fully created as far as KVM is concerned. Originally, kvm_coalesced_mmio_init() was called by kvm_create_vm(), but the original implementation was completely devoid of error handling. Commit 6ce5a090a9a0 ("KVM: coalesced_mmio: fix kvm_coalesced_mmio_init()'s error handling" fixed the various bugs, and in doing so rightly moved the call to after kvm_create_vm() because kvm_coalesced_mmio_init() also registered the coalesced MMIO device. Commit 2b3c246a682c ("KVM: Make coalesced mmio use a device per zone") cleaned up that mess by having each zone register a separate device, i.e. moved device registration to its logical home in kvm_vm_ioctl_register_coalesced_mmio(). As a result, kvm_coalesced_mmio_init() is now a "pure" initialization helper and can be safely called from kvm_create_vm(). Opportunstically drop the #ifdef, KVM provides stubs for kvm_coalesced_mmio_{init,free}() when CONFIG_KVM_MMIO=n (s390). Signed-off-by: Sean Christopherson Message-Id: <20220816053937.2477106-4-seanjc@google.com> Signed-off-by: Paolo Bonzini --- virt/kvm/kvm_main.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) (limited to 'virt/kvm') diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 15e304e059d4..44b92d773156 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -1214,6 +1214,10 @@ static struct kvm *kvm_create_vm(unsigned long type, const char *fdname) if (r) goto out_err_no_mmu_notifier; + r = kvm_coalesced_mmio_init(kvm); + if (r < 0) + goto out_no_coalesced_mmio; + r = kvm_create_vm_debugfs(kvm, fdname); if (r) goto out_err_no_debugfs; @@ -1234,6 +1238,8 @@ static struct kvm *kvm_create_vm(unsigned long type, const char *fdname) out_err: kvm_destroy_vm_debugfs(kvm); out_err_no_debugfs: + kvm_coalesced_mmio_free(kvm); +out_no_coalesced_mmio: #if defined(CONFIG_MMU_NOTIFIER) && defined(KVM_ARCH_WANT_MMU_NOTIFIER) if (kvm->mmu_notifier.ops) mmu_notifier_unregister(&kvm->mmu_notifier, current->mm); @@ -4907,11 +4913,6 @@ static int kvm_dev_ioctl_create_vm(unsigned long type) goto put_fd; } -#ifdef CONFIG_KVM_MMIO - r = kvm_coalesced_mmio_init(kvm); - if (r < 0) - goto put_kvm; -#endif file = anon_inode_getfile("kvm-vm", &kvm_vm_fops, kvm, O_RDWR); if (IS_ERR(file)) { r = PTR_ERR(file); -- cgit v1.2.3-59-g8ed1b