From 0ee8dcb87e403397e575674d0e79272b06dea12e Mon Sep 17 00:00:00 2001 From: Xiao Guangrong Date: Wed, 9 Mar 2011 15:41:59 +0800 Subject: KVM: cleanup memslot_id function We can get memslot id from memslot->id directly Signed-off-by: Xiao Guangrong Signed-off-by: Avi Kivity --- virt/kvm/kvm_main.c | 17 ----------------- 1 file changed, 17 deletions(-) (limited to 'virt/kvm/kvm_main.c') diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 6330653480e4..58146457bf97 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -996,23 +996,6 @@ out: return size; } -int memslot_id(struct kvm *kvm, gfn_t gfn) -{ - int i; - struct kvm_memslots *slots = kvm_memslots(kvm); - struct kvm_memory_slot *memslot = NULL; - - for (i = 0; i < slots->nmemslots; ++i) { - memslot = &slots->memslots[i]; - - if (gfn >= memslot->base_gfn - && gfn < memslot->base_gfn + memslot->npages) - break; - } - - return memslot - slots->memslots; -} - static unsigned long gfn_to_hva_many(struct kvm_memory_slot *slot, gfn_t gfn, gfn_t *nr_pages) { -- cgit v1.2.3 From fa3d315a4ce2c0891cdde262562e710d95fba19e Mon Sep 17 00:00:00 2001 From: Takuya Yoshikawa Date: Sat, 7 May 2011 16:35:38 +0900 Subject: KVM: Validate userspace_addr of memslot when registered This way, we can avoid checking the user space address many times when we read the guest memory. Although we can do the same for write if we check which slots are writable, we do not care write now: reading the guest memory happens more often than writing. [avi: change VERIFY_READ to VERIFY_WRITE] Signed-off-by: Takuya Yoshikawa Signed-off-by: Avi Kivity --- virt/kvm/kvm_main.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) (limited to 'virt/kvm/kvm_main.c') diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 58146457bf97..ed3c4e7c1008 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -648,7 +648,10 @@ int __kvm_set_memory_region(struct kvm *kvm, goto out; if (mem->guest_phys_addr & (PAGE_SIZE - 1)) goto out; - if (user_alloc && (mem->userspace_addr & (PAGE_SIZE - 1))) + /* We can read the guest memory with __xxx_user() later on. */ + if (user_alloc && + ((mem->userspace_addr & (PAGE_SIZE - 1)) || + !access_ok(VERIFY_WRITE, mem->userspace_addr, mem->memory_size))) goto out; if (mem->slot >= KVM_MEMORY_SLOTS + KVM_PRIVATE_MEM_SLOTS) goto out; @@ -1283,7 +1286,7 @@ int kvm_read_guest_page(struct kvm *kvm, gfn_t gfn, void *data, int offset, addr = gfn_to_hva(kvm, gfn); if (kvm_is_error_hva(addr)) return -EFAULT; - r = copy_from_user(data, (void __user *)addr + offset, len); + r = __copy_from_user(data, (void __user *)addr + offset, len); if (r) return -EFAULT; return 0; -- cgit v1.2.3 From 85722cda308c0ad7390dc910139b2ce58c11b9c4 Mon Sep 17 00:00:00 2001 From: OGAWA Hirofumi Date: Wed, 11 May 2011 09:28:28 +0900 Subject: KVM: Fix kvm mmu_notifier initialization order Like the following, mmu_notifier can be called after registering immediately. So, kvm have to initialize kvm->mmu_lock before it. BUG: spinlock bad magic on CPU#0, kswapd0/342 lock: ffff8800af8c4000, .magic: 00000000, .owner: /-1, .owner_cpu: 0 Pid: 342, comm: kswapd0 Not tainted 2.6.39-rc5+ #1 Call Trace: [] spin_bug+0x9c/0xa3 [] do_raw_spin_lock+0x29/0x13c [] ? flush_tlb_others_ipi+0xaf/0xfd [] _raw_spin_lock+0x9/0xb [] kvm_mmu_notifier_clear_flush_young+0x2c/0x66 [kvm] [] __mmu_notifier_clear_flush_young+0x2b/0x57 [] page_referenced_one+0x88/0xea [] page_referenced+0x1fc/0x256 [] shrink_page_list+0x187/0x53a [] shrink_inactive_list+0x1e0/0x33d [] ? determine_dirtyable_memory+0x15/0x27 [] ? call_function_single_interrupt+0xe/0x20 [] shrink_zone+0x322/0x3de [] ? zone_watermark_ok_safe+0xe2/0xf1 [] kswapd+0x516/0x818 [] ? shrink_zone+0x3de/0x3de [] kthread+0x7d/0x85 [] kernel_thread_helper+0x4/0x10 [] ? __init_kthread_worker+0x37/0x37 [] ? gs_change+0xb/0xb Signed-off-by: OGAWA Hirofumi Signed-off-by: Avi Kivity --- virt/kvm/kvm_main.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'virt/kvm/kvm_main.c') diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index ed3c4e7c1008..22cdb960660a 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -467,6 +467,7 @@ static struct kvm *kvm_create_vm(void) if (!kvm->buses[i]) goto out_err; } + spin_lock_init(&kvm->mmu_lock); r = kvm_init_mmu_notifier(kvm); if (r) @@ -474,7 +475,6 @@ static struct kvm *kvm_create_vm(void) kvm->mm = current->mm; atomic_inc(&kvm->mm->mm_count); - spin_lock_init(&kvm->mmu_lock); kvm_eventfd_init(kvm); mutex_init(&kvm->lock); mutex_init(&kvm->irq_lock); -- cgit v1.2.3 From 9e3bb6b6f6a0c535eb053fbf0005a8e79e053374 Mon Sep 17 00:00:00 2001 From: Heiko Carstens Date: Tue, 24 May 2011 07:51:27 +0200 Subject: KVM: add missing void __user * cast to access_ok() call fa3d315a "KVM: Validate userspace_addr of memslot when registered" introduced this new warning onn s390: kvm_main.c: In function '__kvm_set_memory_region': kvm_main.c:654:7: warning: passing argument 1 of '__access_ok' makes pointer from integer without a cast arch/s390/include/asm/uaccess.h:53:19: note: expected 'const void *' but argument is of type '__u64' Add the missing cast to get rid of it again... Cc: Takuya Yoshikawa Signed-off-by: Heiko Carstens Signed-off-by: Avi Kivity --- virt/kvm/kvm_main.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) (limited to 'virt/kvm/kvm_main.c') diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 22cdb960660a..383f492a6603 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -651,7 +651,9 @@ int __kvm_set_memory_region(struct kvm *kvm, /* We can read the guest memory with __xxx_user() later on. */ if (user_alloc && ((mem->userspace_addr & (PAGE_SIZE - 1)) || - !access_ok(VERIFY_WRITE, mem->userspace_addr, mem->memory_size))) + !access_ok(VERIFY_WRITE, + (void __user *)(unsigned long)mem->userspace_addr, + mem->memory_size))) goto out; if (mem->slot >= KVM_MEMORY_SLOTS + KVM_PRIVATE_MEM_SLOTS) goto out; -- cgit v1.2.3 From 74b5c5bfff429f464c38dd49af41d75cf0e7dc26 Mon Sep 17 00:00:00 2001 From: Mike Waychison Date: Fri, 3 Jun 2011 13:04:53 -0700 Subject: KVM: Initialize kvm before registering the mmu notifier It doesn't make sense to ever see a half-initialized kvm structure on mmu notifier callbacks. Previously, 85722cda changed the ordering to ensure that the mmu_lock was initialized before mmu notifier registration, but there is still a race where the mmu notifier could come in and try accessing other portions of struct kvm before they are intialized. Solve this by moving the mmu notifier registration to occur after the structure is completely initialized. Google-Bug-Id: 452199 Signed-off-by: Mike Waychison Signed-off-by: Avi Kivity --- virt/kvm/kvm_main.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) (limited to 'virt/kvm/kvm_main.c') diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 383f492a6603..96ebc0679415 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -467,12 +467,8 @@ static struct kvm *kvm_create_vm(void) if (!kvm->buses[i]) goto out_err; } - spin_lock_init(&kvm->mmu_lock); - - r = kvm_init_mmu_notifier(kvm); - if (r) - goto out_err; + spin_lock_init(&kvm->mmu_lock); kvm->mm = current->mm; atomic_inc(&kvm->mm->mm_count); kvm_eventfd_init(kvm); @@ -480,6 +476,11 @@ static struct kvm *kvm_create_vm(void) mutex_init(&kvm->irq_lock); mutex_init(&kvm->slots_lock); atomic_set(&kvm->users_count, 1); + + r = kvm_init_mmu_notifier(kvm); + if (r) + goto out_err; + raw_spin_lock(&kvm_lock); list_add(&kvm->vm_list, &vm_list); raw_spin_unlock(&kvm_lock); -- cgit v1.2.3