Resurrecting an old issue :) More inline below... > -----Original Message----- > From: linux-nfs-owner@xxxxxxxxxxxxxxx [mailto:linux-nfs- > owner@xxxxxxxxxxxxxxx] On Behalf Of J. Bruce Fields > Sent: Thursday, February 07, 2013 10:42 AM > To: Yan Burman > Cc: linux-nfs@xxxxxxxxxxxxxxx; swise@xxxxxxxxxxxxxxxxxxxxx; linux- > rdma@xxxxxxxxxxxxxxx; Or Gerlitz > Subject: Re: NFS over RDMA crashing > > On Wed, Feb 06, 2013 at 05:24:35PM -0500, J. Bruce Fields wrote: > > On Wed, Feb 06, 2013 at 05:48:15PM +0200, Yan Burman wrote: > > > When killing mount command that got stuck: > > > ------------------------------------------- > > > > > > BUG: unable to handle kernel paging request at ffff880324dc7ff8 > > > IP: [<ffffffffa05f3dfb>] rdma_read_xdr+0x8bb/0xd40 [svcrdma] > > > PGD 1a0c063 PUD 32f82e063 PMD 32f2fd063 PTE 8000000324dc7161 > > > Oops: 0003 [#1] PREEMPT SMP > > > Modules linked in: md5 ib_ipoib xprtrdma svcrdma rdma_cm ib_cm > iw_cm > > > ib_addr nfsd exportfs netconsole ip6table_filter ip6_tables > > > iptable_filter ip_tables ebtable_nat nfsv3 nfs_acl ebtables x_tables > > > nfsv4 auth_rpcgss nfs lockd autofs4 sunrpc target_core_iblock > > > target_core_file target_core_pscsi target_core_mod configfs 8021q > > > bridge stp llc ipv6 dm_mirror dm_region_hash dm_log vhost_net > > > macvtap macvlan tun uinput iTCO_wdt iTCO_vendor_support kvm_intel > > > kvm crc32c_intel microcode pcspkr joydev i2c_i801 lpc_ich mfd_core > > > ehci_pci ehci_hcd sg ioatdma ixgbe mdio mlx4_ib ib_sa ib_mad > ib_core > > > mlx4_en mlx4_core igb hwmon dca ptp pps_core button dm_mod ext3 > jbd > > > sd_mod ata_piix libata uhci_hcd megaraid_sas scsi_mod > > > CPU 6 > > > Pid: 4744, comm: nfsd Not tainted 3.8.0-rc5+ #4 Supermicro > > > X8DTH-i/6/iF/6F/X8DTH > > > RIP: 0010:[<ffffffffa05f3dfb>] [<ffffffffa05f3dfb>] > > > rdma_read_xdr+0x8bb/0xd40 [svcrdma] > > > RSP: 0018:ffff880324c3dbf8 EFLAGS: 00010297 > > > RAX: ffff880324dc8000 RBX: 0000000000000001 RCX: > ffff880324dd8428 > > > RDX: ffff880324dc7ff8 RSI: ffff880324dd8428 RDI: ffffffff81149618 > > > RBP: ffff880324c3dd78 R08: 000060f9c0000860 R09: > 0000000000000001 > > > R10: ffff880324dd8000 R11: 0000000000000001 R12: ffff8806299dcb10 > > > R13: 0000000000000003 R14: 0000000000000001 R15: > 0000000000000010 > > > FS: 0000000000000000(0000) GS:ffff88063fc00000(0000) > knlGS:0000000000000000 > > > CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b > > > CR2: ffff880324dc7ff8 CR3: 0000000001a0b000 CR4: > 00000000000007e0 > > > DR0: 0000000000000000 DR1: 0000000000000000 DR2: > 0000000000000000 > > > DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: > 0000000000000400 > > > Process nfsd (pid: 4744, threadinfo ffff880324c3c000, task > ffff880330550000) > > > Stack: > > > ffff880324c3dc78 ffff880324c3dcd8 0000000000000282 > ffff880631cec000 > > > ffff880324dd8000 ffff88062ed33040 0000000124c3dc48 > ffff880324dd8000 > > > ffff88062ed33058 ffff880630ce2b90 ffff8806299e8000 > 0000000000000003 > > > Call Trace: > > > [<ffffffffa05f466e>] svc_rdma_recvfrom+0x3ee/0xd80 [svcrdma] > > > [<ffffffff81086540>] ? try_to_wake_up+0x2f0/0x2f0 > > > [<ffffffffa045963f>] svc_recv+0x3ef/0x4b0 [sunrpc] > > > [<ffffffffa0571db0>] ? nfsd_svc+0x740/0x740 [nfsd] > > > [<ffffffffa0571e5d>] nfsd+0xad/0x130 [nfsd] > > > [<ffffffffa0571db0>] ? nfsd_svc+0x740/0x740 [nfsd] > > > [<ffffffff81071df6>] kthread+0xd6/0xe0 > > > [<ffffffff81071d20>] ? __init_kthread_worker+0x70/0x70 > > > [<ffffffff814b462c>] ret_from_fork+0x7c/0xb0 > > > [<ffffffff81071d20>] ? __init_kthread_worker+0x70/0x70 > > > Code: 63 c2 49 8d 8c c2 18 02 00 00 48 39 ce 77 e1 49 8b 82 40 0a 00 > > > 00 48 39 c6 0f 84 92 f7 ff ff 90 48 8d 50 f8 49 89 92 40 0a 00 00 > > > <48> c7 40 f8 00 00 00 00 49 8b 82 40 0a 00 00 49 3b 82 30 0a 00 > > > RIP [<ffffffffa05f3dfb>] rdma_read_xdr+0x8bb/0xd40 [svcrdma] > > > RSP <ffff880324c3dbf8> > > > CR2: ffff880324dc7ff8 > > > ---[ end trace 06d0384754e9609a ]--- > > > > > > > > > It seems that commit afc59400d6c65bad66d4ad0b2daf879cbff8e23e > > > "nfsd4: cleanup: replace rq_resused count by rq_next_page pointer" > > > is responsible for the crash (it seems to be crashing in > > > net/sunrpc/xprtrdma/svc_rdma_recvfrom.c:527) > > > It may be because I have CONFIG_DEBUG_SET_MODULE_RONX and > > > CONFIG_DEBUG_RODATA enabled. I did not try to disable them yet. > > > > > > When I moved to commit > 79f77bf9a4e3dd5ead006b8f17e7c4ff07d8374e I > > > was no longer getting the server crashes, > > > so the reset of my tests were done using that point (it is somewhere > > > in the middle of 3.7.0-rc2). > > > > OK, so this part's clearly my fault--I'll work on a patch, but the > > rdma's use of the ->rq_pages array is pretty confusing. > > Does this help? > > They must have added this for some reason, but I'm not seeing how it > could have ever done anything.... > > --b. > > diff --git a/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c > b/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c > index 0ce7552..e8f25ec 100644 > --- a/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c > +++ b/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c > @@ -520,13 +520,6 @@ next_sge: > for (ch_no = 0; &rqstp->rq_pages[ch_no] < rqstp->rq_respages; > ch_no++) > rqstp->rq_pages[ch_no] = NULL; > > - /* > - * Detach res pages. If svc_release sees any it will attempt to > - * put them. > - */ > - while (rqstp->rq_next_page != rqstp->rq_respages) > - *(--rqstp->rq_next_page) = NULL; > - > return err; > } > I can reproduce this server crash readily on a recent net-next tree. I added the above change, and see a different crash: [ 192.764773] BUG: unable to handle kernel paging request at 0000100000000000 [ 192.765688] IP: [<ffffffff8113c159>] put_page+0x9/0x50 [ 192.765688] PGD 0 [ 192.765688] Oops: 0000 [#1] SMP DEBUG_PAGEALLOC [ 192.765688] Modules linked in: nfsd lockd nfs_acl exportfs auth_rpcgss oid_registry svcrdma tg3 ip6table_filter ip6_tables ebtable_nat ebtables nf_conntrack_ipv4 nf_defrag_ipv4 xt_state nf_conntrack ipt_REJECT xt_CHECKSUM iptable_mangle iptable_filter ip_tables bridge stp llc autofs4 sunrpc rdma_ucm rdma_cm iw_cm ib_ipoib ib_cm ib_uverbs ib_umad iw_nes libcrc32c iw_cxgb4 iw_cxgb3 cxgb3 mdio ib_qib dca mlx4_en ib_mthca vhost_net macvtap macvlan vhost tun kvm_intel kvm uinput ipmi_si ipmi_msghandler iTCO_wdt iTCO_vendor_support dcdbas sg microcode pcspkr mlx4_ib ib_sa serio_raw ib_mad ib_core ib_addr ipv6 ptp pps_core lpc_ich mfd_core i5100_edac edac_core mlx4_core cxgb4 ext4 jbd2 mbcache sd_mod crc_t10dif crct10dif_common sr_mod cdrom pata_acpi ata_generic ata_piix radeon ttm drm_kms_helper drm i2c_algo_bit [ 192.765688] i2c_core dm_mirror dm_region_hash dm_log dm_mod [last unloaded: tg3] [ 192.765688] CPU: 1 PID: 6590 Comm: nfsd Not tainted 3.14.0-rc3-pending+ #5 [ 192.765688] Hardware name: Dell Inc. PowerEdge R300/0TY179, BIOS 1.3.0 08/15/2008 [ 192.765688] task: ffff8800b75c62c0 ti: ffff8801faa4a000 task.ti: ffff8801faa4a000 [ 192.765688] RIP: 0010:[<ffffffff8113c159>] [<ffffffff8113c159>] put_page+0x9/0x50 [ 192.765688] RSP: 0018:ffff8801faa4be28 EFLAGS: 00010206 [ 192.765688] RAX: ffff8801fa9542a8 RBX: ffff8801fa954000 RCX: 0000000000000001 [ 192.765688] RDX: ffff8801fa953e10 RSI: 0000000000000200 RDI: 0000100000000000 [ 192.765688] RBP: ffff8801faa4be28 R08: 000000009b8d39b9 R09: 0000000000000017 [ 192.765688] R10: 0000000000000000 R11: 0000000000000000 R12: ffff8800cb2e7c00 [ 192.765688] R13: ffff8801fa954210 R14: 0000000000000000 R15: 0000000000000000 [ 192.765688] FS: 0000000000000000(0000) GS:ffff88022ec80000(0000) knlGS:0000000000000000 [ 192.765688] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b [ 192.765688] CR2: 0000100000000000 CR3: 00000000b9a5a000 CR4: 00000000000007e0 [ 192.765688] Stack: [ 192.765688] ffff8801faa4be58 ffffffffa0881f4e ffff880204dd0e00 ffff8801fa954000 [ 192.765688] ffff880204dd0e00 ffff8800cb2e7c00 ffff8801faa4be88 ffffffffa08825f5 [ 192.765688] ffff8801fa954000 ffff8800b75c62c0 ffffffff81ae5ac0 ffffffffa08cf930 [ 192.765688] Call Trace: [ 192.765688] [<ffffffffa0881f4e>] svc_xprt_release+0x6e/0xf0 [sunrpc] [ 192.765688] [<ffffffffa08825f5>] svc_recv+0x165/0x190 [sunrpc] [ 192.765688] [<ffffffffa08cf930>] ? nfsd_pool_stats_release+0x60/0x60 [nfsd] [ 192.765688] [<ffffffffa08cf9e5>] nfsd+0xb5/0x160 [nfsd] [ 192.765688] [<ffffffffa08cf930>] ? nfsd_pool_stats_release+0x60/0x60 [nfsd] [ 192.765688] [<ffffffff8107471e>] kthread+0xce/0xf0 [ 192.765688] [<ffffffff81074650>] ? kthread_freezable_should_stop+0x70/0x70 [ 192.765688] [<ffffffff81584e2c>] ret_from_fork+0x7c/0xb0 [ 192.765688] [<ffffffff81074650>] ? kthread_freezable_should_stop+0x70/0x70 [ 192.765688] Code: 8d 7b 10 e8 ea fa ff ff 48 c7 03 00 00 00 00 48 83 c4 08 5b c9 c3 66 66 66 2e 0f 1f 84 00 00 00 00 00 55 48 89 e5 66 66 66 66 90 <66> f7 07 00 c0 75 32 8b 47 1c 48 8d 57 1c 85 c0 74 1c f0 ff 0a [ 192.765688] RIP [<ffffffff8113c159>] put_page+0x9/0x50 [ 192.765688] RSP <ffff8801faa4be28> [ 192.765688] CR2: 0000100000000000 crash> -- To unsubscribe from this list: send the line "unsubscribe linux-nfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
