diff options
| author | Ingo Molnar <mingo@elte.hu> | 2006-12-29 16:50:01 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@woody.osdl.org> | 2006-12-30 10:56:44 -0800 |
| commit | 8018c27b26af56af18eb8b2dc600eba825792d8f (patch) | |
| tree | 1125fea536282ff9605f101728a880157796692e | |
| parent | 55a54f79e091d52c3c2835985c347ea4d2e1c21f (diff) | |
| download | lwn-8018c27b26af56af18eb8b2dc600eba825792d8f.tar.gz lwn-8018c27b26af56af18eb8b2dc600eba825792d8f.zip | |
[PATCH] kvm: fix GFP_KERNEL allocation in atomic section in kvm_dev_ioctl_create_vcpu()
fix an GFP_KERNEL allocation in atomic section: kvm_dev_ioctl_create_vcpu()
called kvm_mmu_init(), which calls alloc_pages(), while holding the vcpu.
The fix is to set up the MMU state in two phases: kvm_mmu_create() and
kvm_mmu_setup().
(NOTE: free_vcpus does an kvm_mmu_destroy() call so there's no need for any
extra teardown branch on allocation/init failure here.)
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: Avi Kivity <avi@qumranet.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
| -rw-r--r-- | drivers/kvm/kvm.h | 3 | ||||
| -rw-r--r-- | drivers/kvm/kvm_main.c | 10 | ||||
| -rw-r--r-- | drivers/kvm/mmu.c | 24 |
3 files changed, 17 insertions, 20 deletions
diff --git a/drivers/kvm/kvm.h b/drivers/kvm/kvm.h index 2670219a9264..100df6f38d92 100644 --- a/drivers/kvm/kvm.h +++ b/drivers/kvm/kvm.h @@ -319,7 +319,8 @@ int kvm_init_arch(struct kvm_arch_ops *ops, struct module *module); void kvm_exit_arch(void); void kvm_mmu_destroy(struct kvm_vcpu *vcpu); -int kvm_mmu_init(struct kvm_vcpu *vcpu); +int kvm_mmu_create(struct kvm_vcpu *vcpu); +int kvm_mmu_setup(struct kvm_vcpu *vcpu); int kvm_mmu_reset_context(struct kvm_vcpu *vcpu); void kvm_mmu_slot_remove_write_access(struct kvm *kvm, int slot); diff --git a/drivers/kvm/kvm_main.c b/drivers/kvm/kvm_main.c index 973544553cba..ce7fe640f18d 100644 --- a/drivers/kvm/kvm_main.c +++ b/drivers/kvm/kvm_main.c @@ -522,12 +522,14 @@ static int kvm_dev_ioctl_create_vcpu(struct kvm *kvm, int n) if (r < 0) goto out_free_vcpus; - kvm_arch_ops->vcpu_load(vcpu); + r = kvm_mmu_create(vcpu); + if (r < 0) + goto out_free_vcpus; - r = kvm_arch_ops->vcpu_setup(vcpu); + kvm_arch_ops->vcpu_load(vcpu); + r = kvm_mmu_setup(vcpu); if (r >= 0) - r = kvm_mmu_init(vcpu); - + r = kvm_arch_ops->vcpu_setup(vcpu); vcpu_put(vcpu); if (r < 0) diff --git a/drivers/kvm/mmu.c b/drivers/kvm/mmu.c index 85887fcd584f..790423c5f23d 100644 --- a/drivers/kvm/mmu.c +++ b/drivers/kvm/mmu.c @@ -639,28 +639,22 @@ error_1: return -ENOMEM; } -int kvm_mmu_init(struct kvm_vcpu *vcpu) +int kvm_mmu_create(struct kvm_vcpu *vcpu) { - int r; - ASSERT(vcpu); ASSERT(!VALID_PAGE(vcpu->mmu.root_hpa)); ASSERT(list_empty(&vcpu->free_pages)); - r = alloc_mmu_pages(vcpu); - if (r) - goto out; - - r = init_kvm_mmu(vcpu); - if (r) - goto out_free_pages; + return alloc_mmu_pages(vcpu); +} - return 0; +int kvm_mmu_setup(struct kvm_vcpu *vcpu) +{ + ASSERT(vcpu); + ASSERT(!VALID_PAGE(vcpu->mmu.root_hpa)); + ASSERT(!list_empty(&vcpu->free_pages)); -out_free_pages: - free_mmu_pages(vcpu); -out: - return r; + return init_kvm_mmu(vcpu); } void kvm_mmu_destroy(struct kvm_vcpu *vcpu) |