On Wed, 2012-12-19 at 21:30 +0900, Takuya Yoshikawa wrote: > Ccing Alex, > > I tested kvm.git next branch before Alex's patch set was applied, and > did not see the bug. Although I'm not 100% sure but it is possible > that something got broken by a patch in the following series: > > [01/10] KVM: Restrict non-existing slot state transitions > [02/10] KVM: Check userspace_addr when modifying a memory slot > [03/10] KVM: Fix iommu map/unmap to handle memory slot moves > [04/10] KVM: Minor memory slot optimization > [05/10] KVM: Rename KVM_MEMORY_SLOTS -> KVM_USER_MEM_SLOTS > [06/10] KVM: Make KVM_PRIVATE_MEM_SLOTS optional > [07/10] KVM: struct kvm_memory_slot.user_alloc -> bool > [08/10] KVM: struct kvm_memory_slot.flags -> u32 > [09/10] KVM: struct kvm_memory_slot.id -> short > [10/10] KVM: Increase user memory slots on x86 to 125 > > If I can get time, I will check which one caused the problem tomorrow. Please let me know if you can identify one of these as the culprit. They're all very simple, but there's always a chance I've missed a hard coding of slot numbers somewhere. Thanks, Alex > On Tue, 18 Dec 2012 16:25:58 +0900 > Takuya Yoshikawa <yoshikawa_takuya_b1@xxxxxxxxxxxxx> wrote: > > > IMPORTANT NOTE (not about this patch set): > > > > I have hit the following bug many times with the current next branch, > > even WITHOUT my patches. Although I do not know a way to reproduce this > > yet, it seems that something was broken around slot->dirty_bitmap. I am > > now investigating the new code in __kvm_set_memory_region(). > > > > The bug: > > [ 575.238063] BUG: unable to handle kernel paging request at 00000002efe83a77 > > [ 575.238185] IP: [<ffffffffa05f9619>] mark_page_dirty_in_slot+0x19/0x20 [kvm] > > [ 575.238308] PGD 0 > > [ 575.238343] Oops: 0002 [#1] SMP > > > > The call trace: > > [ 575.241207] Call Trace: > > [ 575.241257] [<ffffffffa05f96b1>] kvm_write_guest_cached+0x91/0xb0 [kvm] > > [ 575.241370] [<ffffffffa0610db9>] kvm_arch_vcpu_ioctl_run+0x1109/0x12c0 [kvm] > > [ 575.241488] [<ffffffffa060fd55>] ? kvm_arch_vcpu_ioctl_run+0xa5/0x12c0 [kvm] > > [ 575.241595] [<ffffffff81679194>] ? mutex_lock_killable_nested+0x274/0x340 > > [ 575.241706] [<ffffffffa05faf80>] ? kvm_set_ioapic_irq+0x20/0x20 [kvm] > > [ 575.241813] [<ffffffffa05f71c9>] kvm_vcpu_ioctl+0x559/0x670 [kvm] > > [ 575.241913] [<ffffffffa05f8a58>] ? kvm_vm_ioctl+0x1b8/0x570 [kvm] > > [ 575.242007] [<ffffffff8101b9d3>] ? native_sched_clock+0x13/0x80 > > [ 575.242125] [<ffffffff8101ba49>] ? sched_clock+0x9/0x10 > > [ 575.242208] [<ffffffff8109015d>] ? sched_clock_cpu+0xbd/0x110 > > [ 575.242298] [<ffffffff811a914c>] ? fget_light+0x3c/0x140 > > [ 575.242381] [<ffffffff8119dfa8>] do_vfs_ioctl+0x98/0x570 > > [ 575.242463] [<ffffffff811a91b1>] ? fget_light+0xa1/0x140 > > [ 575.246393] [<ffffffff811a914c>] ? fget_light+0x3c/0x140 > > [ 575.250363] [<ffffffff8119e511>] sys_ioctl+0x91/0xb0 > > [ 575.254327] [<ffffffff81684c19>] system_call_fastpath+0x16/0x1b -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
