Paolo Bonzini a73896cb5b KVM: vmx: defer load of APIC access page address during reset ... Most call paths to vmx_vcpu_reset do not hold the SRCU lock. Defer loading the APIC access page to the next vmentry. This avoids the following lockdep splat: [ INFO: suspicious RCU usage. ] 3.18.0-rc2-test2+ #70 Not tainted ------------------------------- include/linux/kvm_host.h:474 suspicious rcu_dereference_check() usage! other info that might help us debug this: rcu_scheduler_active = 1, debug_locks = 0 1 lock held by qemu-system-x86/2371: #0: (&vcpu->mutex){+.+...}, at: [<ffffffffa037d800>] vcpu_load+0x20/0xd0 [kvm] stack backtrace: CPU: 4 PID: 2371 Comm: qemu-system-x86 Not tainted 3.18.0-rc2-test2+ #70 Hardware name: Dell Inc. OptiPlex 9010/0M9KCM, BIOS A12 01/10/2013 0000000000000001 ffff880209983ca8 ffffffff816f514f 0000000000000000 ffff8802099b8990 ffff880209983cd8 ffffffff810bd687 00000000000fee00 ffff880208a2c000 ffff880208a10000 ffff88020ef50040 ffff880209983d08 Call Trace: [<ffffffff816f514f>] dump_stack+0x4e/0x71 [<ffffffff810bd687>] lockdep_rcu_suspicious+0xe7/0x120 [<ffffffffa037d055>] gfn_to_memslot+0xd5/0xe0 [kvm] [<ffffffffa03807d3>] __gfn_to_pfn+0x33/0x60 [kvm] [<ffffffffa0380885>] gfn_to_page+0x25/0x90 [kvm] [<ffffffffa038aeec>] kvm_vcpu_reload_apic_access_page+0x3c/0x80 [kvm] [<ffffffffa08f0a9c>] vmx_vcpu_reset+0x20c/0x460 [kvm_intel] [<ffffffffa039ab8e>] kvm_vcpu_reset+0x15e/0x1b0 [kvm] [<ffffffffa039ac0c>] kvm_arch_vcpu_setup+0x2c/0x50 [kvm] [<ffffffffa037f7e0>] kvm_vm_ioctl+0x1d0/0x780 [kvm] [<ffffffff810bc664>] ? __lock_is_held+0x54/0x80 [<ffffffff812231f0>] do_vfs_ioctl+0x300/0x520 [<ffffffff8122ee45>] ? __fget+0x5/0x250 [<ffffffff8122f0fa>] ? __fget_light+0x2a/0xe0 [<ffffffff81223491>] SyS_ioctl+0x81/0xa0 [<ffffffff816fed6d>] system_call_fastpath+0x16/0x1b Reported-by: Takashi Iwai <tiwai@suse.de> Reported-by: Alexei Starovoitov <alexei.starovoitov@gmail.com> Reviewed-by: Wanpeng Li <wanpeng.li@linux.intel.com> Tested-by: Wanpeng Li <wanpeng.li@linux.intel.com> Fixes: 38b9917350 Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>		2014-11-02 08:37:18 +01:00
..
cpuid.c	KVM: nested VMX: disable perf cpuid reporting	2014-09-24 14:07:50 +02:00
cpuid.h	KVM: x86: Warn if guest virtual address space is not 48-bits	2014-09-24 14:07:48 +02:00
emulate.c	KVM: x86: Fix far-jump to non-canonical check	2014-11-02 07:54:55 +01:00
i8254.c	KVM: x86: Improve thread safety in pit	2014-10-24 13:21:14 +02:00
i8254.h
i8259.c
irq.c
irq.h
Kconfig
kvm_cache_regs.h
lapic.c	KVM: x86: make apic_accept_irq tracepoint more generic	2014-09-11 11:51:02 +02:00
lapic.h
Makefile
mmu_audit.c
mmu.c	Merge branch 'for-3.18' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu	2014-10-10 07:26:02 -04:00
mmu.h
mmutrace.h
paging_tmpl.h	KVM: x86: Wrong assertion on paging_tmpl.h	2014-10-24 13:30:37 +02:00
pmu.c
svm.c	kvm: x86: don't kill guest on unknown exit reason	2014-10-24 13:21:17 +02:00
trace.h	KVM: x86: make apic_accept_irq tracepoint more generic	2014-09-11 11:51:02 +02:00
tss.h
vmx.c	KVM: vmx: defer load of APIC access page address during reset	2014-11-02 08:37:18 +01:00
x86.c	KVM: x86: Prevent host from panicking on shared MSR writes.	2014-10-24 13:21:08 +02:00
x86.h	KVM: vmx: Inject #GP on invalid PAT CR	2014-09-24 14:07:52 +02:00