leandrof/linux
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity
90d83dc3d4
linux/arch/x86
History
Lai Jiangshan 90d83dc3d4 KVM: use the correct RCU API for PROVE_RCU=y 
The RCU/SRCU API have already changed for proving RCU usage.

I got the following dmesg when PROVE_RCU=y because we used incorrect API.
This patch coverts rcu_deference() to srcu_dereference() or family API.

===================================================
[ INFO: suspicious rcu_dereference_check() usage. ]
---------------------------------------------------
arch/x86/kvm/mmu.c:3020 invoked rcu_dereference_check() without protection!

other info that might help us debug this:

rcu_scheduler_active = 1, debug_locks = 0
2 locks held by qemu-system-x86/8550:
 #0:  (&kvm->slots_lock){+.+.+.}, at: [<ffffffffa011a6ac>] kvm_set_memory_region+0x29/0x50 [kvm]
 #1:  (&(&kvm->mmu_lock)->rlock){+.+...}, at: [<ffffffffa012262d>] kvm_arch_commit_memory_region+0xa6/0xe2 [kvm]

stack backtrace:
Pid: 8550, comm: qemu-system-x86 Not tainted 2.6.34-rc4-tip-01028-g939eab1 #27
Call Trace:
 [<ffffffff8106c59e>] lockdep_rcu_dereference+0xaa/0xb3
 [<ffffffffa012f6c1>] kvm_mmu_calculate_mmu_pages+0x44/0x7d [kvm]
 [<ffffffffa012263e>] kvm_arch_commit_memory_region+0xb7/0xe2 [kvm]
 [<ffffffffa011a5d7>] __kvm_set_memory_region+0x636/0x6e2 [kvm]
 [<ffffffffa011a6ba>] kvm_set_memory_region+0x37/0x50 [kvm]
 [<ffffffffa015e956>] vmx_set_tss_addr+0x46/0x5a [kvm_intel]
 [<ffffffffa0126592>] kvm_arch_vm_ioctl+0x17a/0xcf8 [kvm]
 [<ffffffff810a8692>] ? unlock_page+0x27/0x2c
 [<ffffffff810bf879>] ? __do_fault+0x3a9/0x3e1
 [<ffffffffa011b12f>] kvm_vm_ioctl+0x364/0x38d [kvm]
 [<ffffffff81060cfa>] ? up_read+0x23/0x3d
 [<ffffffff810f3587>] vfs_ioctl+0x32/0xa6
 [<ffffffff810f3b19>] do_vfs_ioctl+0x495/0x4db
 [<ffffffff810e6b2f>] ? fget_light+0xc2/0x241
 [<ffffffff810e416c>] ? do_sys_open+0x104/0x116
 [<ffffffff81382d6d>] ? retint_swapgs+0xe/0x13
 [<ffffffff810f3ba6>] sys_ioctl+0x47/0x6a
 [<ffffffff810021db>] system_call_fastpath+0x16/0x1b

Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-05-17 12:18:01 +03:00
..
boot Merge branch 'x86-setup-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2010-02-28 10:43:53 -08:00
configs
crypto include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
ia32 x86: correctly wire up the newuname system call 2010-04-20 09:17:21 -07:00
include/asm Merge branch 'perf' 2010-05-17 12:17:58 +03:00
kernel Merge branch 'perf' 2010-05-17 12:17:58 +03:00
kvm KVM: use the correct RCU API for PROVE_RCU=y 2010-05-17 12:18:01 +03:00
lguest lguest: stop using KVM hypercall mechanism 2010-04-14 21:43:56 +09:30
lib perf, x86: Add INSTRUCTION_DECODER config flag 2010-03-10 13:34:12 +01:00
math-emu
mm Merge branch 'master' into export-slabh 2010-04-05 11:37:28 +09:00
oprofile perf, x86: Undo some some *_counter* -> *_event* renames 2010-04-02 19:52:02 +02:00
pci include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
power Merge branch 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/x86/linux-2.6-tip 2010-04-07 11:02:23 -07:00
tools x86: Remove trailing spaces in messages 2010-02-07 17:47:51 +01:00
vdso include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
video
xen include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
Kbuild
Kconfig Merge branch 'linus' into perf/core 2010-04-08 13:37:18 +02:00
Kconfig.cpu x86, perf, bts, mm: Delete the never used BTS-ptrace code 2010-03-26 11:33:55 +01:00
Kconfig.debug x86, perf, bts, mm: Delete the never used BTS-ptrace code 2010-03-26 11:33:55 +01:00
Makefile x86-64: Allow fbdev primary video code 2010-02-16 21:22:26 -08:00
Makefile_32.cpu Merge branch 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2009-12-08 13:38:11 -08:00