From mboxrd@z Thu Jan 1 00:00:00 1970 From: Avi Kivity Subject: Re: [PATCH] KVM: VMX: fix rcu usage warning Date: Tue, 08 Jun 2010 11:11:13 +0300 Message-ID: <4C0DFB21.7050309@redhat.com> References: <4C0DA7D7.5@cn.fujitsu.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Cc: Marcelo Tosatti , LKML , KVM list To: Xiao Guangrong Return-path: In-Reply-To: <4C0DA7D7.5@cn.fujitsu.com> Sender: linux-kernel-owner@vger.kernel.org List-Id: kvm.vger.kernel.org On 06/08/2010 05:15 AM, Xiao Guangrong wrote: > fix: > > [ INFO: suspicious rcu_dereference_check() usage. ] > --------------------------------------------------- > include/linux/kvm_host.h:258 invoked rcu_dereference_check() without protection! > > other info that might help us debug this: > > > rcu_scheduler_active = 1, debug_locks = 1 > 1 lock held by qemu-system-x86/3796: > #0: (&vcpu->mutex){+.+.+.}, at: [] vcpu_load+0x1a/0x66 [kvm] > > stack backtrace: > Pid: 3796, comm: qemu-system-x86 Not tainted 2.6.34 #25 > Call Trace: > [] lockdep_rcu_dereference+0x9d/0xa5 > [] gfn_to_memslot_unaliased+0x65/0xa0 [kvm] > [] gfn_to_hva+0x22/0x4c [kvm] > [] kvm_write_guest_page+0x2a/0x7f [kvm] > [] kvm_clear_guest_page+0x1a/0x1c [kvm] > [] init_rmode+0x3b/0x180 [kvm_intel] > [] vmx_set_cr0+0x350/0x4d3 [kvm_intel] > [] kvm_arch_vcpu_ioctl_set_sregs+0x122/0x31a [kvm] > [] kvm_vcpu_ioctl+0x578/0xa3d [kvm] > [] ? cpu_clock+0x2d/0x40 > [] ? fget_light+0x244/0x28e > [] ? trace_hardirqs_off_caller+0x1f/0x10e > [] vfs_ioctl+0x32/0xa6 > [] do_vfs_ioctl+0x47f/0x4b8 > [] ? sub_preempt_count+0xa3/0xb7 > [] ? fget_light+0x266/0x28e > [] ? fget_light+0x111/0x28e > [] sys_ioctl+0x47/0x6a > [] system_call_fastpath+0x16/0x1b > > Applied, thanks. -- error compiling committee.c: too many arguments to function