====================================== | [ 2.278596] #PF: supervisor read access in kernel mode | [ 2.278629] #PF: error_code(0x0000) - not-present page | [ 2.278661] PGD 0 P4D 0 | [ 2.278680] Oops: 0000 [#1] PREEMPT SMP NOPTI [ 2.278756] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014 [ 2.278820] RIP: 0010:sock_wfree (./arch/x86/include/asm/bitops.h:206 ./arch/x86/include/asm/bitops.h:238 ./include/asm-generic/bitops/instrumented-non-atomic.h:142 net/core/sock.c:3399 net/core/sock.c:2470) [ 2.278858] Code: 6b 45 6b ff 84 db 0f 84 b6 fe ff ff e9 10 ff ff ff be 03 00 00 00 4c 89 e7 e8 41 8a a6 ff e9 61 ff ff ff 48 8b 85 20 01 00 00 <48> 8b 50 08 83 e2 04 74 cc f0 80 60 08 fb eb 99 48 8b bd 00 01 00 All code ======== 0: 6b 45 6b ff imul $0xffffffff,0x6b(%rbp),%eax 4: 84 db test %bl,%bl 6: 0f 84 b6 fe ff ff je 0xfffffffffffffec2 c: e9 10 ff ff ff jmp 0xffffffffffffff21 11: be 03 00 00 00 mov $0x3,%esi 16: 4c 89 e7 mov %r12,%rdi 19: e8 41 8a a6 ff call 0xffffffffffa68a5f 1e: e9 61 ff ff ff jmp 0xffffffffffffff84 23: 48 8b 85 20 01 00 00 mov 0x120(%rbp),%rax 2a:* 48 8b 50 08 mov 0x8(%rax),%rdx <-- trapping instruction 2e: 83 e2 04 and $0x4,%edx 31: 74 cc je 0xffffffffffffffff 33: f0 80 60 08 fb lock andb $0xfb,0x8(%rax) 38: eb 99 jmp 0xffffffffffffffd3 3a: 48 rex.W 3b: 8b .byte 0x8b 3c: bd .byte 0xbd 3d: 00 01 add %al,(%rcx) ... Code starting with the faulting instruction =========================================== 0: 48 8b 50 08 mov 0x8(%rax),%rdx 4: 83 e2 04 and $0x4,%edx 7: 74 cc je 0xffffffffffffffd5 9: f0 80 60 08 fb lock andb $0xfb,0x8(%rax) e: eb 99 jmp 0xffffffffffffffa9 10: 48 rex.W 11: 8b .byte 0x8b 12: bd .byte 0xbd 13: 00 01 add %al,(%rcx) ... [ 2.278954] RSP: 0018:ffffa78f40148e30 EFLAGS: 00010206 [ 2.278985] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000003dc0 [ 2.279029] RDX: 0000000000001d40 RSI: ffff9379c13d4000 RDI: 0000000000000000 [ 2.279074] RBP: ffff9379c23fe3c0 R08: ffff9379c12690ac R09: 0000000000000001 [ 2.279118] R10: ffffffffad2060c0 R11: ffffa78f40148ff8 R12: ffff9379c23fe53c [ 2.279162] R13: 000000000000004b R14: 0000000000000000 R15: ffff9379c13d4000 [ 2.279209] FS: 0000000000000000(0000) GS:ffff9379fed80000(0000) knlGS:0000000000000000 [ 2.279253] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 2.279289] CR2: 0000000000000008 CR3: 000000000271e005 CR4: 0000000000770ef0 [ 2.279335] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 2.279378] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 2.279422] PKRU: 55555554 [ 2.279441] Call Trace: [ 2.279459] [ 2.279484] ? __die (arch/x86/kernel/dumpstack.c:421 arch/x86/kernel/dumpstack.c:434) [ 2.279515] ? page_fault_oops (arch/x86/mm/fault.c:713) [ 2.279541] ? find_busiest_group (kernel/sched/fair.c:10845) [ 2.279572] ? exc_page_fault (./arch/x86/include/asm/irqflags.h:37 ./arch/x86/include/asm/irqflags.h:72 arch/x86/mm/fault.c:1513 arch/x86/mm/fault.c:1563) [ 2.279597] ? asm_exc_page_fault (./arch/x86/include/asm/idtentry.h:623) [ 2.279623] ? sock_wfree (./arch/x86/include/asm/bitops.h:206 ./arch/x86/include/asm/bitops.h:238 ./include/asm-generic/bitops/instrumented-non-atomic.h:142 net/core/sock.c:3399 net/core/sock.c:2470) [ 2.279649] skb_release_head_state (net/core/skbuff.c:1162) [ 2.279683] consume_skb (net/core/skbuff.c:1174 net/core/skbuff.c:1189 net/core/skbuff.c:1411 net/core/skbuff.c:1405) [ 2.279707] dummy_xmit (drivers/net/dummy.c:66) [ 2.279739] dev_hard_start_xmit (./include/linux/netdevice.h:4877 ./include/linux/netdevice.h:4891 net/core/dev.c:3564 net/core/dev.c:3580) [ 2.279768] sch_direct_xmit (net/sched/sch_generic.c:343) [ 2.279797] __qdisc_run (net/sched/sch_generic.c:416) [ 2.279821] ? __hrtimer_run_queues (kernel/time/hrtimer.c:1707 kernel/time/hrtimer.c:1756) [ 2.279853] net_tx_action (./include/net/sch_generic.h:217 ./include/net/pkt_sched.h:128 ./include/net/pkt_sched.h:124 net/core/dev.c:5267) [ 2.279879] __do_softirq (kernel/softirq.c:554) [ 2.279906] irq_exit_rcu (kernel/softirq.c:428 kernel/softirq.c:633 kernel/softirq.c:645) [ 2.279932] sysvec_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:1043 arch/x86/kernel/apic/apic.c:1043) [ 2.279966] [ 2.279982] [ 2.279996] asm_sysvec_apic_timer_interrupt (./arch/x86/include/asm/idtentry.h:702) [ 2.280030] RIP: 0010:default_idle (./arch/x86/include/asm/irqflags.h:37 ./arch/x86/include/asm/irqflags.h:72 arch/x86/kernel/process.c:743) [ 2.280057] Code: 4c 01 c7 4c 29 c2 e9 72 ff ff ff 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d d3 fb 24 00 fb f4 c3 cc cc cc cc 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 All code ======== 0: 4c 01 c7 add %r8,%rdi 3: 4c 29 c2 sub %r8,%rdx 6: e9 72 ff ff ff jmp 0xffffffffffffff7d b: 90 nop c: 90 nop d: 90 nop e: 90 nop f: 90 nop 10: 90 nop 11: 90 nop 12: 90 nop 13: 90 nop 14: 90 nop 15: 90 nop 16: 90 nop 17: 90 nop 18: 90 nop 19: 90 nop 1a: 90 nop 1b: f3 0f 1e fa endbr64 1f: 66 90 xchg %ax,%ax 21: 0f 00 2d d3 fb 24 00 verw 0x24fbd3(%rip) # 0x24fbfb 28: fb sti 29: f4 hlt 2a:* fa cli <-- trapping instruction 2b: c3 ret 2c: cc int3 2d: cc int3 2e: cc int3 2f: cc int3 30: 66 66 2e 0f 1f 84 00 data16 cs nopw 0x0(%rax,%rax,1) 37: 00 00 00 00 3b: 90 nop 3c: 90 nop 3d: 90 nop 3e: 90 nop 3f: 90 nop Code starting with the faulting instruction =========================================== 0: fa cli 1: c3 ret 2: cc int3 3: cc int3 4: cc int3 5: cc int3 6: 66 66 2e 0f 1f 84 00 data16 cs nopw 0x0(%rax,%rax,1) d: 00 00 00 00 11: 90 nop 12: 90 nop 13: 90 nop 14: 90 nop 15: 90 nop [ 2.280154] RSP: 0018:ffffa78f400bbee8 EFLAGS: 00000256 [ 2.280186] RAX: ffff9379fed80000 RBX: ffff9379c1379700 RCX: 0000000000000000 [ 2.280231] RDX: 4000000000000000 RSI: ffffffffacea1591 RDI: 000000000001ffcc [ 2.280276] RBP: 0000000000000003 R08: 000000000001ffcc R09: 0000000000000001 [ 2.280321] R10: 0000000000000001 R11: 0000000000000002 R12: 0000000000000000 [ 2.280367] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 [ 2.280407] default_idle_call (./include/linux/cpuidle.h:144 kernel/sched/idle.c:118) [ 2.280431] do_idle (kernel/sched/idle.c:192 kernel/sched/idle.c:332) [ 2.280458] cpu_startup_entry (kernel/sched/idle.c:429 (discriminator 1)) [ 2.280486] start_secondary (arch/x86/kernel/smpboot.c:313) Finger prints: sock_wfree:skb_release_head_state:consume_skb:dummy_xmit