From 3da0dd433dc399a8c0124d0614d82a09b6a49bce Mon Sep 17 00:00:00 2001 From: Izik Eidus Date: Wed, 23 Sep 2009 21:47:18 +0300 Subject: KVM: add support for change_pte mmu notifiers this is needed for kvm if it want ksm to directly map pages into its shadow page tables. [marcelo: cast pfn assignment to u64] Signed-off-by: Izik Eidus Signed-off-by: Marcelo Tosatti --- virt/kvm/kvm_main.c | 14 ++++++++++++++ 1 file changed, 14 insertions(+) (limited to 'virt/kvm') diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index e79c54034bcd..b7c78a403dc2 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -850,6 +850,19 @@ static void kvm_mmu_notifier_invalidate_page(struct mmu_notifier *mn, } +static void kvm_mmu_notifier_change_pte(struct mmu_notifier *mn, + struct mm_struct *mm, + unsigned long address, + pte_t pte) +{ + struct kvm *kvm = mmu_notifier_to_kvm(mn); + + spin_lock(&kvm->mmu_lock); + kvm->mmu_notifier_seq++; + kvm_set_spte_hva(kvm, address, pte); + spin_unlock(&kvm->mmu_lock); +} + static void kvm_mmu_notifier_invalidate_range_start(struct mmu_notifier *mn, struct mm_struct *mm, unsigned long start, @@ -929,6 +942,7 @@ static const struct mmu_notifier_ops kvm_mmu_notifier_ops = { .invalidate_range_start = kvm_mmu_notifier_invalidate_range_start, .invalidate_range_end = kvm_mmu_notifier_invalidate_range_end, .clear_flush_young = kvm_mmu_notifier_clear_flush_young, + .change_pte = kvm_mmu_notifier_change_pte, .release = kvm_mmu_notifier_release, }; #endif /* CONFIG_MMU_NOTIFIER && KVM_ARCH_WANT_MMU_NOTIFIER */ -- cgit v1.2.3-70-g09d2 From 0ea4ed8e948c30f88c824c973ee4b9529015fe65 Mon Sep 17 00:00:00 2001 From: "Darrick J. Wong" Date: Wed, 14 Oct 2009 16:21:00 -0700 Subject: KVM: Prevent kvm_init from corrupting debugfs structures I'm seeing an oops condition when kvm-intel and kvm-amd are modprobe'd during boot (say on an Intel system) and then rmmod'd: # modprobe kvm-intel kvm_init() kvm_init_debug() kvm_arch_init() <-- stores debugfs dentries internally (success, etc) # modprobe kvm-amd kvm_init() kvm_init_debug() <-- second initialization clobbers kvm's internal pointers to dentries kvm_arch_init() kvm_exit_debug() <-- and frees them # rmmod kvm-intel kvm_exit() kvm_exit_debug() <-- double free of debugfs files! *BOOM* If execution gets to the end of kvm_init(), then the calling module has been established as the kvm provider. Move the debugfs initialization to the end of the function, and remove the now-unnecessary call to kvm_exit_debug() from the error path. That way we avoid trampling on the debugfs entries and freeing them twice. Cc: stable@kernel.org Signed-off-by: Darrick J. Wong Signed-off-by: Marcelo Tosatti --- virt/kvm/kvm_main.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) (limited to 'virt/kvm') diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index b7c78a403dc2..7495ce347344 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -2717,8 +2717,6 @@ int kvm_init(void *opaque, unsigned int vcpu_size, int r; int cpu; - kvm_init_debug(); - r = kvm_arch_init(opaque); if (r) goto out_fail; @@ -2785,6 +2783,8 @@ int kvm_init(void *opaque, unsigned int vcpu_size, kvm_preempt_ops.sched_in = kvm_sched_in; kvm_preempt_ops.sched_out = kvm_sched_out; + kvm_init_debug(); + return 0; out_free: @@ -2807,7 +2807,6 @@ out_free_0: out: kvm_arch_exit(); out_fail: - kvm_exit_debug(); return r; } EXPORT_SYMBOL_GPL(kvm_init); @@ -2815,6 +2814,7 @@ EXPORT_SYMBOL_GPL(kvm_init); void kvm_exit(void) { tracepoint_synchronize_unregister(); + kvm_exit_debug(); misc_deregister(&kvm_dev); kmem_cache_destroy(kvm_vcpu_cache); sysdev_unregister(&kvm_sysdev); @@ -2824,7 +2824,6 @@ void kvm_exit(void) on_each_cpu(hardware_disable, NULL, 1); kvm_arch_hardware_unsetup(); kvm_arch_exit(); - kvm_exit_debug(); free_cpumask_var(cpus_hardware_enabled); __free_page(bad_page); } -- cgit v1.2.3-70-g09d2