From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Zhang, Yanmin" Subject: IPF Montvale machine panic when running a network-relevent testing Date: Fri, 13 Jun 2008 16:19:20 +0800 Message-ID: <1213345160.25608.3.camel@ymzhang> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: LKML , Linux-IA64 To: netdev@vger.kernel.org Return-path: Sender: linux-ia64-owner@vger.kernel.org List-Id: netdev.vger.kernel.org With kernel 2.6.26-rc5 and a git kernel just between rc4 and rc5, my kernel panic on my Montvale machine when I did an initial specweb2005 testing between 2 machines. Below is the log. LOGIN: Unable to handle kernel NULL pointer dereference (address 000000= 0000000000) Thread-7266[13494]: Oops 8804682956800 [1] Modules linked in: Pid: 13494, CPU 0, comm: Thread-7266 psr : 0000101008026018 ifs : 800000000000050e ip : [= ] Not tainted (2.6.26-rc4git) ip is at tcp_rcv_established+0x1450/0x16e0 unat: 0000000000000000 pfs : 000000000000050e rsc : 0000000000000003 rnat: 0000000000000000 bsps: 0000000000000000 pr : 000000000059656b ldrs: 0000000000000000 ccv : 0000000000000000 fpsr: 0009804c8a70033f csd : 0000000000000000 ssd : 0000000000000000 b0 : a00000010087a410 b6 : a0000001004c7ac0 b7 : a0000001004c64e0 f6 : 000000000000000000000 f7 : 1003e0000000000000b80 f8 : 10000821f080500000000 f9 : 1003efffffffffffffa58 f10 : 1003edbb7db5f6be58df8 f11 : 1003e0000000000000015 r1 : a0000001010cce90 r2 : e0000003d4530c40 r3 : 0000000000000105 r8 : e000000402533d68 r9 : e000000402533a80 r10 : e000000402533bfc r11 : 0000000000000004 r12 : e0000003d4537df0 r13 : e0000003d4530000 r14 : 0000000000000000 r15 : e000000401fca180 r16 : e0000003d4530c68 r17 : e000000402572238 r18 : 00000000000000ff r19 : a0000001012c6630 r20 : e0000003d4530c68 r21 : e000000401fca480 r22 : e000000402572658 r23 : e000000402572240 r24 : a0000001012c4e04 r25 : 0000000000000003 r26 : e000000401fca4a8 r27 : e000000402572660 r28 : e00000040a2d2a00 r29 : e00000040a6f83a8 r30 : e00000040a6f8300 r31 : 000000000000000a Call Trace: [] show_stack+0x40/0xa0 sp=3De0000003d45379c0 bsp=3De0000003d45= 31440 [] show_regs+0x850/0x8a0 sp=3De0000003d4537b90 bsp=3De0000003d45= 313e0 [] die+0x230/0x360 sp=3De0000003d4537b90 bsp=3De0000003d45= 31398 [] ia64_do_page_fault+0x8e0/0xa40 sp=3De0000003d4537b90 bsp=3De0000003d45= 31348 [] ia64_leave_kernel+0x0/0x280 sp=3De0000003d4537c20 bsp=3De0000003d45= 31348 [] tcp_rcv_established+0x1450/0x16e0 sp=3De0000003d4537df0 bsp=3De0000003d45= 312d8 [] tcp_v4_do_rcv+0x70/0x500 sp=3De0000003d4537df0 bsp=3De0000003d45= 31298 [] tcp_v4_rcv+0xfb0/0x1060 sp=3De0000003d4537e00 bsp=3De0000003d45= 31248 As a matter of fact, kernel paniced at statement "queue->rskq_accept_tail->dl_next =3D req" in function =EF=BB=BFreqsk_q= ueue_add, because =EF=BB=BFqueue->rskq_accept_tail is NULL. The call chain is: =EF=BB=BF=EF=BB=BFtcp_rcv_established =3D> inet_csk_reqsk_queue_add =3D= > reqsk_queue_add. As I was running an initial specweb2005(configured 3500 sessions) testi= ng between 2 machines, there were lots of failure and many network connections wer= e reestablished during the testing. In function tcp_v4_rcv, bh_lock_sock_nested(sk) (a kind of spinlock) is= used to avoid race. But inet_csk_accept uses lock_sock(sk) (a kind of sleeper).= Although lock_sock also accesses sk->sk_lock.slock, it looks like there is a rac= e. -yanmin -- To unsubscribe from this list: send the line "unsubscribe linux-ia64" i= n the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html