On Mon, Feb 11, 2013 at 03:19:42PM +0000, Yan Burman wrote: > > -----Original Message----- > > From: J. Bruce Fields [mailto:bfields@xxxxxxxxxxxx] > > Sent: Thursday, February 07, 2013 18:42 > > 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've been trying to reproduce the problem, but for some reason it does not happen anymore. > The crash is not happening even without the patch now, but NFS over RDMA in 3.8.0-rc5 from net-next is not working. > When running server and client in VM with SRIOV, it times out when trying to mount and oopses on the client when mount command is interrupted. > When running two physical hosts, I get to mount the remote directory, but reading or writing fails with IO error. > > I am still doing some checks - I will post my findings when I will have more information. OK, thanks for keeping us updated. --b. -- 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
