On Thu, Dec 10, 2015 at 06:38:57PM +0100, Paolo Bonzini wrote:
> Invoking tracepoints within kvm_guest_enter/kvm_guest_exit causes a
> lockdep splat.
>
> Cc: stable@xxxxxxxxxxxxxxx
> Reported-by: Borislav Petkov <bp@xxxxxxxxx>
> Signed-off-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>
> ---
> arch/x86/kvm/svm.c | 4 ++--
> arch/x86/kvm/vmx.c | 3 ++-
> arch/x86/kvm/x86.c | 2 +-
> 3 files changed, 5 insertions(+), 4 deletions(-)
Looks like you missed some...
[ 144.296364] kvm: zapping shadow pages for mmio generation wraparound
[ 164.699053] kvm: zapping shadow pages for mmio generation wraparound
[ 312.115767] kvm: zapping shadow pages for mmio generation wraparound
[ 432.277585] kvm: zapping shadow pages for mmio generation wraparound
[ 434.547820] ===============================
[ 434.552020] [ INFO: suspicious RCU usage. ]
[ 434.556223] 4.4.0-rc4+ #1 Not tainted
[ 434.559886] -------------------------------
[ 434.564072] arch/x86/kvm/trace.h:971 suspicious rcu_dereference_check() usage!
[ 434.571303]
other info that might help us debug this:
[ 434.579324]
RCU used illegally from idle CPU!
rcu_scheduler_active = 1, debug_locks = 0
[ 434.590209] RCU used illegally from extended quiescent state!
[ 434.595971] 1 lock held by qemu-system-x86/2402:
[ 434.600596] #0: (&vcpu->mutex){+.+.+.}, at: [<ffffffffa020872c>] vcpu_load+0x1c/0x80 [kvm]
[ 434.609146]
stack backtrace:
[ 434.613526] CPU: 4 PID: 2402 Comm: qemu-system-x86 Not tainted 4.4.0-rc4+ #1
[ 434.620583] Hardware name: Dell Inc. Precision T3600/0PTTT9, BIOS A13 05/11/2014
[ 434.627987] 0000000000000001 ffff88042f79fcf0 ffffffff813c2cfc ffff880435aa0000
[ 434.635443] ffff88042f79fd20 ffffffff810c5157 ffff88042fd48000 0000000295a85563
[ 434.642886] 0000000295de483f 0000000000000000 ffff88042f79fd58 ffffffffa023ec6e
[ 434.650334] Call Trace:
[ 434.652804] [<ffffffff813c2cfc>] dump_stack+0x4e/0x82
[ 434.657950] [<ffffffff810c5157>] lockdep_rcu_suspicious+0xe7/0x120
[ 434.664239] [<ffffffffa023ec6e>] wait_lapic_expire+0xfe/0x1e0 [kvm]
[ 434.670606] [<ffffffffa022183e>] kvm_arch_vcpu_ioctl_run+0x76e/0x19c0 [kvm]
[ 434.677674] [<ffffffffa0221982>] ? kvm_arch_vcpu_ioctl_run+0x8b2/0x19c0 [kvm]
[ 434.684905] [<ffffffff81858acc>] ? mutex_lock_killable_nested+0x29c/0x4c0
[ 434.691792] [<ffffffffa0208b32>] kvm_vcpu_ioctl+0x342/0x700 [kvm]
[ 434.697984] [<ffffffff810c4a7d>] ? __lock_is_held+0x4d/0x70
[ 434.703655] [<ffffffff812351ae>] ? __fget+0xfe/0x200
[ 434.708719] [<ffffffff812291f1>] do_vfs_ioctl+0x301/0x550
[ 434.714208] [<ffffffff8123531a>] ? __fget_light+0x2a/0x90
[ 434.719700] [<ffffffff81229481>] SyS_ioctl+0x41/0x70
[ 434.724754] [<ffffffff8185cb36>] entry_SYSCALL_64_fastpath+0x16/0x7a
[ 437.411818] kvm [2400]: vcpu0 unhandled rdmsr: 0x606
[ 437.416898] kvm [2400]: vcpu0 unhandled rdmsr: 0x34
--
Regards/Gruss,
Boris.
ECO tip #101: Trim your mails when you reply.
--
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
