Bug 624783
| Summary: | lockdep: suspicious rcu_dereference_check() usage | ||||||
|---|---|---|---|---|---|---|---|
| Product: | [Fedora] Fedora | Reporter: | Jurgen Kramer <gtmkramer> | ||||
| Component: | kernel | Assignee: | Kernel Maintainer List <kernel-maint> | ||||
| Status: | CLOSED DUPLICATE | QA Contact: | Fedora Extras Quality Assurance <extras-qa> | ||||
| Severity: | medium | Docs Contact: | |||||
| Priority: | low | ||||||
| Version: | 14 | CC: | anton, aquini, dougsland, gansalmon, itamar, jonathan, kernel-maint, madhu.chinakonda | ||||
| Target Milestone: | --- | ||||||
| Target Release: | --- | ||||||
| Hardware: | All | ||||||
| OS: | Linux | ||||||
| Whiteboard: | |||||||
| Fixed In Version: | Doc Type: | Bug Fix | |||||
| Doc Text: | Story Points: | --- | |||||
| Clone Of: | Environment: | ||||||
| Last Closed: | 2010-08-18 12:39:38 UTC | Type: | --- | ||||
| Regression: | --- | Mount Type: | --- | ||||
| Documentation: | --- | CRM: | |||||
| Verified Versions: | Category: | --- | |||||
| oVirt Team: | --- | RHEL 7.3 requirements from Atomic Host: | |||||
| Cloudforms Team: | --- | Target Upstream Version: | |||||
| Embargoed: | |||||||
| Attachments: |
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Created attachment 439189 [details]
Full dmesg output
*** This bug has been marked as a duplicate of bug 622149 *** |
Description of problem: When booting F14 alpha RC4 I saw a lockdep problem when checking /var/log/messages. Version-Release number of selected component (if applicable): 2.6.35-3.fc14.x86_64 How reproducible: always Steps to Reproduce: 1. Boot F14 alpha RC4 in F13 x86_64 KVM 2. 3. Actual results: Lockdep issue appears Expected results: No lockdep Additional info: I first saw this message on a fresh F14 alpha RC4 with kernel 2.6.35-0.57.rc6.git1.fc14.x86_64 after updating the problem persists. This is with F14 x86_64 alpha RC4 updated (17 aug 2010) running in KVM on a F13 x86_64 host with 2 vCPUs and 2048MB memory appointed to it. Setting APIC routing to flat ..TIMER: vector=0x30 apic1=0 pin1=2 apic2=-1 pin2=-1 CPU0: Intel QEMU Virtual CPU version 0.12.3 stepping 03 lockdep: fixing up alternatives. =================================================== [ INFO: suspicious rcu_dereference_check() usage. ] --------------------------------------------------- kernel/sched.c:616 invoked rcu_dereference_check() without protection! other info that might help us debug this: rcu_scheduler_active = 1, debug_locks = 0 3 locks held by swapper/1: #0: (cpu_add_remove_lock){+.+.+.}, at: [<ffffffff81052b4b>] cpu_maps_update_begin+0x17/0x19 #1: (cpu_hotplug.lock){+.+.+.}, at: [<ffffffff81052a5e>] cpu_hotplug_begin+0x2c/0x53 #2: (&rq->lock){-.-...}, at: [<ffffffff81491989>] init_idle+0x30/0x131 stack backtrace: Pid: 1, comm: swapper Not tainted 2.6.35-3.fc14.x86_64 #1 Call Trace: [<ffffffff8107bc62>] lockdep_rcu_dereference+0xaa/0xb3 [<ffffffff8103fda5>] task_group+0x80/0x8f [<ffffffff8103fdcb>] set_task_rq+0x17/0x73 [<ffffffff81491a43>] init_idle+0xea/0x131 [<ffffffff81491e13>] fork_idle+0x92/0xa3 [<ffffffff8107e748>] ? mark_held_locks+0x50/0x72 [<ffffffff8148f8b9>] do_fork_idle+0x1c/0x2d [<ffffffff8148fa01>] do_boot_cpu+0x137/0x9ac [<ffffffff8148f89d>] ? do_fork_idle+0x0/0x2d [<ffffffff81490a9a>] native_cpu_up+0x100/0x1c2 [<ffffffff81491eec>] _cpu_up+0x9d/0xf9 [<ffffffff8149201b>] cpu_up+0xd3/0xe5 [<ffffffff81d78d86>] kernel_init+0x105/0x2c9 [<ffffffff8100aae4>] kernel_thread_helper+0x4/0x10 [<ffffffff814991d0>] ? restore_args+0x0/0x30 [<ffffffff81d78c81>] ? kernel_init+0x0/0x2c9 [<ffffffff8100aae0>] ? kernel_thread_helper+0x0/0x10 Booting Node 0, Processors #1 Ok. kvm-clock: cpu 1, msr 0:53d5a81, secondary cpu clock Brought up 2 CPUs Total of 2 processors activated (10689.24 BogoMIPS). sizeof(vma)=176 bytes sizeof(page)=56 bytes sizeof(inode)=1168 bytes sizeof(dentry)=256 bytes sizeof(ext3inode)=1600 bytes sizeof(buffer_head)=104 bytes sizeof(skbuff)=240 bytes sizeof(task_struct)=9216 bytes