On 08/26/14 at 08:25am, Petr Tesarik wrote: > On Tue, 26 Aug 2014 11:22:47 +0800 > "bhe at redhat.com" <bhe at redhat.com> wrote: > > >[...] > > Here it use lseek to position, then try to read, and then reading failed > > and raised a SIGKILL. > > > > lseek(3, 8799381360640, SEEK_SET) = 8799381360640 > > read(3, <unfinished ...> > > +++ killed by SIGKILL +++ > > Killed > > This smells like killed by OOM Killer. Can you check the kernel log if > there's anything? Thanks for notice, it is caused by kernel addr validation check in read_kcore. No idea why it happened. [ +35.288439] BUG: unable to handle kernel paging request at ffff8800c4000000 [ +0.011559] IP: [<ffffffff8105870b>] kern_addr_valid+0x15b/0x1b0 [ +0.010586] PGD 220f067 PUD 2213067 PMD 80000000c4000062 [ +0.009994] Oops: 0000 [#1] SMP [ +0.007782] Modules linked in: xt_CHECKSUM nf_conntrack_netbios_ns nf_conntrack_broadcast ipt_MASQUERADE ip6t_REJECT xt_conntrack cfg80211 rfki [ +0.084041] CPU: 2 PID: 1679 Comm: makedumpfile Not tainted 3.17.0-rc2 #15 [ +0.012249] Hardware name: Dell Inc. PowerEdge T105 /0J001K, BIOS 1.4.4 07/30/2009 [ +0.012991] task: ffff8800c010ae40 ti: ffff880214830000 task.ti: ffff880214830000 [ +0.012886] RIP: 0010:[<ffffffff8105870b>] [<ffffffff8105870b>] kern_addr_valid+0x15b/0x1b0 [ +0.013860] RSP: 0018:ffff880214833e88 EFLAGS: 00010206 [ +0.010710] RAX: 00000000c4000000 RBX: 0000000000001000 RCX: 0000000000000000 [ +0.012445] RDX: 00000000c4000000 RSI: ffff880000000000 RDI: 80000000c4000062 [ +0.012298] RBP: ffff880214833e88 R08: 000000000000000e R09: 00007fffffffffff [ +0.012322] R10: 0000000000000001 R11: 0000000000000246 R12: 0000000000001000 [ +0.012316] R13: 00000000022beb10 R14: ffff880214833f50 R15: ffff8800c4000000 [ +0.012308] FS: 00007f0c91ffa740(0000) GS:ffff88022fd00000(0000) knlGS:0000000000000000 [ +0.013315] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ +0.010985] CR2: ffff8800c4000000 CR3: 000000021a632000 CR4: 00000000000007e0 [ +0.012266] Stack: [ +0.006976] ffff880214833ee0 ffffffff81255c38 ffff880214929410 0000000000000000 [ +0.012471] 0000000d14833ed8 0000000000001000 ffff880223c7c480 00000000022beb10 [ +0.012465] ffff880214833f50 0000000000001000 00007ffffe1840c0 ffff880214833f00 [ +0.012456] Call Trace: [ +0.007459] [<ffffffff81255c38>] read_kcore+0x228/0x300 [ +0.010392] [<ffffffff8124962d>] proc_reg_read+0x3d/0x80 [ +0.010491] [<ffffffff811e58f8>] vfs_read+0x98/0x170 [ +0.010153] [<ffffffff811e6576>] SyS_read+0x46/0xb0 [ +0.010034] [<ffffffff8111d5f6>] ? __audit_syscall_exit+0x1f6/0x2a0 [ +0.011425] [<ffffffff8181dea9>] system_call_fastpath+0x16/0x1b [ +0.011072] Code: 48 89 f8 66 66 66 90 48 be 00 f0 ff ff ff 3f 00 00 48 c1 ea 09 48 21 f0 81 e2 f8 0f 00 00 48 be 00 00 00 00 00 88 ff ff 48 01 [ +0.030537] RIP [<ffffffff8105870b>] kern_addr_valid+0x15b/0x1b0 [ +0.011666] RSP <ffff880214833e88> [ +0.009043] CR2: ffff8800c4000000 [ +0.042194] ---[ end trace 97512601fec12186 ]---
