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2020-01-26SUNRPC: Fix backchannel latency metricsChuck Lever
commit 8729aaba74626c4ebce3abf1b9e96bb62d2958ca upstream. I noticed that for callback requests, the reported backlog latency is always zero, and the rtt value is crazy big. The problem was that rqst->rq_xtime is never set for backchannel requests. Fixes: 78215759e20d ("SUNRPC: Make RTT measurement more ... ") Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-26SUNRPC: Fix svcauth_gss_proxy_init()Chuck Lever
commit 5866efa8cbfbadf3905072798e96652faf02dbe8 upstream. gss_read_proxy_verf() assumes things about the XDR buffer containing the RPC Call that are not true for buffers generated by svc_rdma_recv(). RDMA's buffers look more like what the upper layer generates for sending: head is a kmalloc'd buffer; it does not point to a page whose contents are contiguous with the first page in the buffers' page array. The result is that ACCEPT_SEC_CONTEXT via RPC/RDMA has stopped working on Linux NFS servers that use gssproxy. This does not affect clients that use only TCP to send their ACCEPT_SEC_CONTEXT operation (that's all Linux clients). Other clients, like Solaris NFS clients, send ACCEPT_SEC_CONTEXT on the same transport as they send all other NFS operations. Such clients can send ACCEPT_SEC_CONTEXT via RPC/RDMA. I thought I had found every direct reference in the server RPC code to the rqstp->rq_pages field. Bug found at the 2019 Westford NFS bake-a-thon. Fixes: 3316f0631139 ("svcrdma: Persistently allocate and DMA- ... ") Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Tested-by: Bill Baker <bill.baker@oracle.com> Reviewed-by: Simo Sorce <simo@redhat.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-17xprtrdma: Fix oops in Receive handler after device removalChuck Lever
commit 671c450b6fe0680ea1cb1cf1526d764fdd5a3d3f upstream. Since v5.4, a device removal occasionally triggered this oops: Dec 2 17:13:53 manet kernel: BUG: unable to handle page fault for address: 0000000c00000219 Dec 2 17:13:53 manet kernel: #PF: supervisor read access in kernel mode Dec 2 17:13:53 manet kernel: #PF: error_code(0x0000) - not-present page Dec 2 17:13:53 manet kernel: PGD 0 P4D 0 Dec 2 17:13:53 manet kernel: Oops: 0000 [#1] SMP Dec 2 17:13:53 manet kernel: CPU: 2 PID: 468 Comm: kworker/2:1H Tainted: G W 5.4.0-00050-g53717e43af61 #883 Dec 2 17:13:53 manet kernel: Hardware name: Supermicro SYS-6028R-T/X10DRi, BIOS 1.1a 10/16/2015 Dec 2 17:13:53 manet kernel: Workqueue: ib-comp-wq ib_cq_poll_work [ib_core] Dec 2 17:13:53 manet kernel: RIP: 0010:rpcrdma_wc_receive+0x7c/0xf6 [rpcrdma] Dec 2 17:13:53 manet kernel: Code: 6d 8b 43 14 89 c1 89 45 78 48 89 4d 40 8b 43 2c 89 45 14 8b 43 20 89 45 18 48 8b 45 20 8b 53 14 48 8b 30 48 8b 40 10 48 8b 38 <48> 8b 87 18 02 00 00 48 85 c0 75 18 48 8b 05 1e 24 c4 e1 48 85 c0 Dec 2 17:13:53 manet kernel: RSP: 0018:ffffc900035dfe00 EFLAGS: 00010246 Dec 2 17:13:53 manet kernel: RAX: ffff888467290000 RBX: ffff88846c638400 RCX: 0000000000000048 Dec 2 17:13:53 manet kernel: RDX: 0000000000000048 RSI: 00000000f942e000 RDI: 0000000c00000001 Dec 2 17:13:53 manet kernel: RBP: ffff888467611b00 R08: ffff888464e4a3c4 R09: 0000000000000000 Dec 2 17:13:53 manet kernel: R10: ffffc900035dfc88 R11: fefefefefefefeff R12: ffff888865af4428 Dec 2 17:13:53 manet kernel: R13: ffff888466023000 R14: ffff88846c63f000 R15: 0000000000000010 Dec 2 17:13:53 manet kernel: FS: 0000000000000000(0000) GS:ffff88846fa80000(0000) knlGS:0000000000000000 Dec 2 17:13:53 manet kernel: CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 Dec 2 17:13:53 manet kernel: CR2: 0000000c00000219 CR3: 0000000002009002 CR4: 00000000001606e0 Dec 2 17:13:53 manet kernel: Call Trace: Dec 2 17:13:53 manet kernel: __ib_process_cq+0x5c/0x14e [ib_core] Dec 2 17:13:53 manet kernel: ib_cq_poll_work+0x26/0x70 [ib_core] Dec 2 17:13:53 manet kernel: process_one_work+0x19d/0x2cd Dec 2 17:13:53 manet kernel: ? cancel_delayed_work_sync+0xf/0xf Dec 2 17:13:53 manet kernel: worker_thread+0x1a6/0x25a Dec 2 17:13:53 manet kernel: ? cancel_delayed_work_sync+0xf/0xf Dec 2 17:13:53 manet kernel: kthread+0xf4/0xf9 Dec 2 17:13:53 manet kernel: ? kthread_queue_delayed_work+0x74/0x74 Dec 2 17:13:53 manet kernel: ret_from_fork+0x24/0x30 The proximal cause is that this rpcrdma_rep has a rr_rdmabuf that is still pointing to the old ib_device, which has been freed. The only way that is possible is if this rpcrdma_rep was not destroyed by rpcrdma_ia_remove. Debugging showed that was indeed the case: this rpcrdma_rep was still in use by a completing RPC at the time of the device removal, and thus wasn't on the rep free list. So, it was not found by rpcrdma_reps_destroy(). The fix is to introduce a list of all rpcrdma_reps so that they all can be found when a device is removed. That list is used to perform only regbuf DMA unmapping, replacing that call to rpcrdma_reps_destroy(). Meanwhile, to prevent corruption of this list, I've moved the destruction of temp rpcrdma_rep objects to rpcrdma_post_recvs(). rpcrdma_xprt_drain() ensures that post_recvs (and thus rep_destroy) is not invoked while rpcrdma_reps_unmap is walking rb_all_reps, thus protecting the rb_all_reps list. Fixes: b0b227f071a0 ("xprtrdma: Use an llist to manage free rpcrdma_reps") Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-17xprtrdma: Fix completion wait during device removalChuck Lever
commit 13cb886c591f341a8759f175292ddf978ef903a1 upstream. I've found that on occasion, "rmmod <dev>" will hang while if an NFS is under load. Ensure that ri_remove_done is initialized only just before the transport is woken up to force a close. This avoids the completion possibly getting initialized again while the CM event handler is waiting for a wake-up. Fixes: bebd031866ca ("xprtrdma: Support unplugging an HCA from under an NFS mount") Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-17xprtrdma: Fix create_qp crash on device unloadChuck Lever
commit b32b9ed493f938e191f790a0991d20b18b38c35b upstream. On device re-insertion, the RDMA device driver crashes trying to set up a new QP: Nov 27 16:32:06 manet kernel: BUG: kernel NULL pointer dereference, address: 00000000000001c0 Nov 27 16:32:06 manet kernel: #PF: supervisor write access in kernel mode Nov 27 16:32:06 manet kernel: #PF: error_code(0x0002) - not-present page Nov 27 16:32:06 manet kernel: PGD 0 P4D 0 Nov 27 16:32:06 manet kernel: Oops: 0002 [#1] SMP Nov 27 16:32:06 manet kernel: CPU: 1 PID: 345 Comm: kworker/u28:0 Tainted: G W 5.4.0 #852 Nov 27 16:32:06 manet kernel: Hardware name: Supermicro SYS-6028R-T/X10DRi, BIOS 1.1a 10/16/2015 Nov 27 16:32:06 manet kernel: Workqueue: xprtiod xprt_rdma_connect_worker [rpcrdma] Nov 27 16:32:06 manet kernel: RIP: 0010:atomic_try_cmpxchg+0x2/0x12 Nov 27 16:32:06 manet kernel: Code: ff ff 48 8b 04 24 5a c3 c6 07 00 0f 1f 40 00 c3 31 c0 48 81 ff 08 09 68 81 72 0c 31 c0 48 81 ff 83 0c 68 81 0f 92 c0 c3 8b 06 <f0> 0f b1 17 0f 94 c2 84 d2 75 02 89 06 88 d0 c3 53 ba 01 00 00 00 Nov 27 16:32:06 manet kernel: RSP: 0018:ffffc900035abbf0 EFLAGS: 00010046 Nov 27 16:32:06 manet kernel: RAX: 0000000000000000 RBX: 00000000000001c0 RCX: 0000000000000000 Nov 27 16:32:06 manet kernel: RDX: 0000000000000001 RSI: ffffc900035abbfc RDI: 00000000000001c0 Nov 27 16:32:06 manet kernel: RBP: ffffc900035abde0 R08: 000000000000000e R09: ffffffffffffc000 Nov 27 16:32:06 manet kernel: R10: 0000000000000000 R11: 000000000002e800 R12: ffff88886169d9f8 Nov 27 16:32:06 manet kernel: R13: ffff88886169d9f4 R14: 0000000000000246 R15: 0000000000000000 Nov 27 16:32:06 manet kernel: FS: 0000000000000000(0000) GS:ffff88846fa40000(0000) knlGS:0000000000000000 Nov 27 16:32:06 manet kernel: CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 Nov 27 16:32:06 manet kernel: CR2: 00000000000001c0 CR3: 0000000002009006 CR4: 00000000001606e0 Nov 27 16:32:06 manet kernel: Call Trace: Nov 27 16:32:06 manet kernel: do_raw_spin_lock+0x2f/0x5a Nov 27 16:32:06 manet kernel: create_qp_common.isra.47+0x856/0xadf [mlx4_ib] Nov 27 16:32:06 manet kernel: ? slab_post_alloc_hook.isra.60+0xa/0x1a Nov 27 16:32:06 manet kernel: ? __kmalloc+0x125/0x139 Nov 27 16:32:06 manet kernel: mlx4_ib_create_qp+0x57f/0x972 [mlx4_ib] The fix is to copy the qp_init_attr struct that was just created by rpcrdma_ep_create() instead of using the one from the previous connection instance. Fixes: 98ef77d1aaa7 ("xprtrdma: Send Queue size grows after a reconnect") Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-17xprtrdma: Close window between waking RPC senders and posting ReceivesChuck Lever
commit 2ae50ad68cd79224198b525f7bd645c9da98b6ff upstream. A recent clean up attempted to separate Receive handling and RPC Reply processing, in the name of clean layering. Unfortunately, we can't do this because the Receive Queue has to be refilled _after_ the most recent credit update from the responder is parsed from the transport header, but _before_ we wake up the next RPC sender. That is right in the middle of rpcrdma_reply_handler(). Usually this isn't a problem because current responder implementations don't vary their credit grant. The one exception is when a connection is established: the grant goes from one to a much larger number on the first Receive. The requester MUST post enough Receives right then so that any outstanding requests can be sent without risking RNR and connection loss. Fixes: 6ceea36890a0 ("xprtrdma: Refactor Receive accounting") Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-17xprtrdma: Fix MR list handlingChuck Lever
commit c3700780a096fc66467c81076ddf7f3f11d639b5 upstream. Close some holes introduced by commit 6dc6ec9e04c4 ("xprtrdma: Cache free MRs in each rpcrdma_req") that could result in list corruption. In addition, the result that is tabulated in @count is no longer used, so @count is removed. Fixes: 6dc6ec9e04c4 ("xprtrdma: Cache free MRs in each rpcrdma_req") Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-17xprtrdma: Connection becomes unstable after a reconnectChuck Lever
commit a31b2f939219dd9bffdf01a45bd91f209f8cc369 upstream. This is because xprt_request_get_cong() is allowing more than one RPC Call to be transmitted before the first Receive on the new connection. The first Receive fills the Receive Queue based on the server's credit grant. Before that Receive, there is only a single Receive WR posted because the client doesn't know the server's credit grant. Solution is to clear rq_cong on all outstanding rpc_rqsts when the the cwnd is reset. This is because an RPC/RDMA credit is good for one connection instance only. Fixes: 75891f502f5f ("SUNRPC: Support for congestion control ... ") Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-17xprtrdma: Add unique trace points for posting Local Invalidate WRsChuck Lever
commit 4b93dab36f28e673725e5e6123ebfccf7697f96a upstream. When adding frwr_unmap_async way back when, I re-used the existing trace_xprtrdma_post_send() trace point to record the return code of ib_post_send. Unfortunately there are some cases where re-using that trace point causes a crash. Instead, construct a trace point specific to posting Local Invalidate WRs that will always be safe to use in that context, and will act as a trace log eye-catcher for Local Invalidation. Fixes: 847568942f93 ("xprtrdma: Remove fr_state") Fixes: d8099feda483 ("xprtrdma: Reduce context switching due ... ") Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Tested-by: Bill Baker <bill.baker@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-09sunrpc: fix crash when cache_head become valid before updatePavel Tikhomirov
commit 5fcaf6982d1167f1cd9b264704f6d1ef4c505d54 upstream. I was investigating a crash in our Virtuozzo7 kernel which happened in in svcauth_unix_set_client. I found out that we access m_client field in ip_map structure, which was received from sunrpc_cache_lookup (we have a bit older kernel, now the code is in sunrpc_cache_add_entry), and these field looks uninitialized (m_client == 0x74 don't look like a pointer) but in the cache_head in flags we see 0x1 which is CACHE_VALID. It looks like the problem appeared from our previous fix to sunrpc (1): commit 4ecd55ea0742 ("sunrpc: fix cache_head leak due to queued request") And we've also found a patch already fixing our patch (2): commit d58431eacb22 ("sunrpc: don't mark uninitialised items as VALID.") Though the crash is eliminated, I think the core of the problem is not completely fixed: Neil in the patch (2) makes cache_head CACHE_NEGATIVE, before cache_fresh_locked which was added in (1) to fix crash. These way cache_is_valid won't say the cache is valid anymore and in svcauth_unix_set_client the function cache_check will return error instead of 0, and we don't count entry as initialized. But it looks like we need to remove cache_fresh_locked completely in sunrpc_cache_lookup: In (1) we've only wanted to make cache_fresh_unlocked->cache_dequeue so that cache_requests with no readers also release corresponding cache_head, to fix their leak. We with Vasily were not sure if cache_fresh_locked and cache_fresh_unlocked should be used in pair or not, so we've guessed to use them in pair. Now we see that we don't want the CACHE_VALID bit set here by cache_fresh_locked, as "valid" means "initialized" and there is no initialization in sunrpc_cache_add_entry. Both expiry_time and last_refresh are not used in cache_fresh_unlocked code-path and also not required for the initial fix. So to conclude cache_fresh_locked was called by mistake, and we can just safely remove it instead of crutching it with CACHE_NEGATIVE. It looks ideologically better for me. Hope I don't miss something here. Here is our crash backtrace: [13108726.326291] BUG: unable to handle kernel NULL pointer dereference at 0000000000000074 [13108726.326365] IP: [<ffffffffc01f79eb>] svcauth_unix_set_client+0x2ab/0x520 [sunrpc] [13108726.326448] PGD 0 [13108726.326468] Oops: 0002 [#1] SMP [13108726.326497] Modules linked in: nbd isofs xfs loop kpatch_cumulative_81_0_r1(O) xt_physdev nfnetlink_queue bluetooth rfkill ip6table_nat nf_nat_ipv6 ip_vs_wrr ip_vs_wlc ip_vs_sh nf_conntrack_netlink ip_vs_sed ip_vs_pe_sip nf_conntrack_sip ip_vs_nq ip_vs_lc ip_vs_lblcr ip_vs_lblc ip_vs_ftp ip_vs_dh nf_nat_ftp nf_conntrack_ftp iptable_raw xt_recent nf_log_ipv6 xt_hl ip6t_rt nf_log_ipv4 nf_log_common xt_LOG xt_limit xt_TCPMSS xt_tcpmss vxlan ip6_udp_tunnel udp_tunnel xt_statistic xt_NFLOG nfnetlink_log dummy xt_mark xt_REDIRECT nf_nat_redirect raw_diag udp_diag tcp_diag inet_diag netlink_diag af_packet_diag unix_diag rpcsec_gss_krb5 xt_addrtype ip6t_rpfilter ipt_REJECT nf_reject_ipv4 ip6t_REJECT nf_reject_ipv6 ebtable_nat ebtable_broute nf_conntrack_ipv6 nf_defrag_ipv6 ip6table_mangle ip6table_raw nfsv4 [13108726.327173] dns_resolver cls_u32 binfmt_misc arptable_filter arp_tables ip6table_filter ip6_tables devlink fuse_kio_pcs ipt_MASQUERADE nf_nat_masquerade_ipv4 xt_nat iptable_nat nf_nat_ipv4 xt_comment nf_conntrack_ipv4 nf_defrag_ipv4 xt_wdog_tmo xt_multiport bonding xt_set xt_conntrack iptable_filter iptable_mangle kpatch(O) ebtable_filter ebt_among ebtables ip_set_hash_ip ip_set nfnetlink vfat fat skx_edac intel_powerclamp coretemp intel_rapl iosf_mbi kvm_intel kvm irqbypass fuse pcspkr ses enclosure joydev sg mei_me hpwdt hpilo lpc_ich mei ipmi_si shpchp ipmi_devintf ipmi_msghandler xt_ipvs acpi_power_meter ip_vs_rr nfsv3 nfsd auth_rpcgss nfs_acl nfs lockd grace fscache nf_nat cls_fw sch_htb sch_cbq sch_sfq ip_vs em_u32 nf_conntrack tun br_netfilter veth overlay ip6_vzprivnet ip6_vznetstat ip_vznetstat [13108726.327817] ip_vzprivnet vziolimit vzevent vzlist vzstat vznetstat vznetdev vzmon vzdev bridge pio_kaio pio_nfs pio_direct pfmt_raw pfmt_ploop1 ploop ip_tables ext4 mbcache jbd2 sd_mod crc_t10dif crct10dif_generic mgag200 i2c_algo_bit drm_kms_helper scsi_transport_iscsi 8021q syscopyarea sysfillrect garp sysimgblt fb_sys_fops mrp stp ttm llc bnx2x crct10dif_pclmul crct10dif_common crc32_pclmul crc32c_intel drm dm_multipath ghash_clmulni_intel uas aesni_intel lrw gf128mul glue_helper ablk_helper cryptd tg3 smartpqi scsi_transport_sas mdio libcrc32c i2c_core usb_storage ptp pps_core wmi sunrpc dm_mirror dm_region_hash dm_log dm_mod [last unloaded: kpatch_cumulative_82_0_r1] [13108726.328403] CPU: 35 PID: 63742 Comm: nfsd ve: 51332 Kdump: loaded Tainted: G W O ------------ 3.10.0-862.20.2.vz7.73.29 #1 73.29 [13108726.328491] Hardware name: HPE ProLiant DL360 Gen10/ProLiant DL360 Gen10, BIOS U32 10/02/2018 [13108726.328554] task: ffffa0a6a41b1160 ti: ffffa0c2a74bc000 task.ti: ffffa0c2a74bc000 [13108726.328610] RIP: 0010:[<ffffffffc01f79eb>] [<ffffffffc01f79eb>] svcauth_unix_set_client+0x2ab/0x520 [sunrpc] [13108726.328706] RSP: 0018:ffffa0c2a74bfd80 EFLAGS: 00010246 [13108726.328750] RAX: 0000000000000001 RBX: ffffa0a6183ae000 RCX: 0000000000000000 [13108726.328811] RDX: 0000000000000074 RSI: 0000000000000286 RDI: ffffa0c2a74bfcf0 [13108726.328864] RBP: ffffa0c2a74bfe00 R08: ffffa0bab8c22960 R09: 0000000000000001 [13108726.328916] R10: 0000000000000001 R11: 0000000000000001 R12: ffffa0a32aa7f000 [13108726.328969] R13: ffffa0a6183afac0 R14: ffffa0c233d88d00 R15: ffffa0c2a74bfdb4 [13108726.329022] FS: 0000000000000000(0000) GS:ffffa0e17f9c0000(0000) knlGS:0000000000000000 [13108726.329081] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [13108726.332311] CR2: 0000000000000074 CR3: 00000026a1b28000 CR4: 00000000007607e0 [13108726.334606] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [13108726.336754] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [13108726.338908] PKRU: 00000000 [13108726.341047] Call Trace: [13108726.343074] [<ffffffff8a2c78b4>] ? groups_alloc+0x34/0x110 [13108726.344837] [<ffffffffc01f5eb4>] svc_set_client+0x24/0x30 [sunrpc] [13108726.346631] [<ffffffffc01f2ac1>] svc_process_common+0x241/0x710 [sunrpc] [13108726.348332] [<ffffffffc01f3093>] svc_process+0x103/0x190 [sunrpc] [13108726.350016] [<ffffffffc07d605f>] nfsd+0xdf/0x150 [nfsd] [13108726.351735] [<ffffffffc07d5f80>] ? nfsd_destroy+0x80/0x80 [nfsd] [13108726.353459] [<ffffffff8a2bf741>] kthread+0xd1/0xe0 [13108726.355195] [<ffffffff8a2bf670>] ? create_kthread+0x60/0x60 [13108726.356896] [<ffffffff8a9556dd>] ret_from_fork_nospec_begin+0x7/0x21 [13108726.358577] [<ffffffff8a2bf670>] ? create_kthread+0x60/0x60 [13108726.360240] Code: 4c 8b 45 98 0f 8e 2e 01 00 00 83 f8 fe 0f 84 76 fe ff ff 85 c0 0f 85 2b 01 00 00 49 8b 50 40 b8 01 00 00 00 48 89 93 d0 1a 00 00 <f0> 0f c1 02 83 c0 01 83 f8 01 0f 8e 53 02 00 00 49 8b 44 24 38 [13108726.363769] RIP [<ffffffffc01f79eb>] svcauth_unix_set_client+0x2ab/0x520 [sunrpc] [13108726.365530] RSP <ffffa0c2a74bfd80> [13108726.367179] CR2: 0000000000000074 Fixes: d58431eacb22 ("sunrpc: don't mark uninitialised items as VALID.") Signed-off-by: Pavel Tikhomirov <ptikhomirov@virtuozzo.com> Acked-by: NeilBrown <neilb@suse.de> Signed-off-by: J. Bruce Fields <bfields@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-12-13SUNRPC: Avoid RPC delays when exiting suspendTrond Myklebust
commit 66eb3add452aa1be65ad536da99fac4b8f620b74 upstream. Jon Hunter: "I have been tracking down another suspend/NFS related issue where again I am seeing random delays exiting suspend. The delays can be up to a couple minutes in the worst case and this is causing a suspend test we have to fail." Change the use of a deferrable work to a standard delayed one. Reported-by: Jon Hunter <jonathanh@nvidia.com> Tested-by: Jon Hunter <jonathanh@nvidia.com> Fixes: 7e0a0e38fcfea ("SUNRPC: Replace the queue timer with a delayed work function") Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-10-30SUNRPC: Destroy the back channel when we destroy the host transportTrond Myklebust
When we're destroying the host transport mechanism, we should ensure that we do not leak memory by failing to release any back channel slots that might still exist. Reported-by: Neil Brown <neilb@suse.de> Reported-by: kbuild test robot <lkp@intel.com> Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-10-30SUNRPC: The RDMA back channel mustn't disappear while requests are outstandingTrond Myklebust
If there are RDMA back channel requests being processed by the server threads, then we should hold a reference to the transport to ensure it doesn't get freed from underneath us. Reported-by: Neil Brown <neilb@suse.de> Fixes: 63cae47005af ("xprtrdma: Handle incoming backward direction RPC calls") Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-10-30SUNRPC: The TCP back channel mustn't disappear while requests are outstandingTrond Myklebust
If there are TCP back channel requests being processed by the server threads, then we should hold a reference to the transport to ensure it doesn't get freed from underneath us. Reported-by: Neil Brown <neilb@suse.de> Fixes: 2ea24497a1b3 ("SUNRPC: RPC callbacks may be split across several..") Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-10-10SUNRPC: fix race to sk_err after xs_error_reportBenjamin Coddington
Since commit 4f8943f80883 ("SUNRPC: Replace direct task wakeups from softirq context") there has been a race to the value of the sk_err if both XPRT_SOCK_WAKE_ERROR and XPRT_SOCK_WAKE_DISCONNECT are set. In that case, we may end up losing the sk_err value that existed when xs_error_report was called. Fix this by reverting to the previous behavior: instead of using SO_ERROR to retrieve the value at a later time (which might also return sk_err_soft), copy the sk_err value onto struct sock_xprt, and use that value to wake pending tasks. Signed-off-by: Benjamin Coddington <bcodding@redhat.com> Fixes: 4f8943f80883 ("SUNRPC: Replace direct task wakeups from softirq context") Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-09-27Merge tag 'nfsd-5.4' of git://linux-nfs.org/~bfields/linuxLinus Torvalds
Pull nfsd updates from Bruce Fields: "Highlights: - Add a new knfsd file cache, so that we don't have to open and close on each (NFSv2/v3) READ or WRITE. This can speed up read and write in some cases. It also replaces our readahead cache. - Prevent silent data loss on write errors, by treating write errors like server reboots for the purposes of write caching, thus forcing clients to resend their writes. - Tweak the code that allocates sessions to be more forgiving, so that NFSv4.1 mounts are less likely to hang when a server already has a lot of clients. - Eliminate an arbitrary limit on NFSv4 ACL sizes; they should now be limited only by the backend filesystem and the maximum RPC size. - Allow the server to enforce use of the correct kerberos credentials when a client reclaims state after a reboot. And some miscellaneous smaller bugfixes and cleanup" * tag 'nfsd-5.4' of git://linux-nfs.org/~bfields/linux: (34 commits) sunrpc: clean up indentation issue nfsd: fix nfs read eof detection nfsd: Make nfsd_reset_boot_verifier_locked static nfsd: degraded slot-count more gracefully as allocation nears exhaustion. nfsd: handle drc over-allocation gracefully. nfsd: add support for upcall version 2 nfsd: add a "GetVersion" upcall for nfsdcld nfsd: Reset the boot verifier on all write I/O errors nfsd: Don't garbage collect files that might contain write errors nfsd: Support the server resetting the boot verifier nfsd: nfsd_file cache entries should be per net namespace nfsd: eliminate an unnecessary acl size limit Deprecate nfsd fault injection nfsd: remove duplicated include from filecache.c nfsd: Fix the documentation for svcxdr_tmpalloc() nfsd: Fix up some unused variable warnings nfsd: close cached files prior to a REMOVE or RENAME that would replace target nfsd: rip out the raparms cache nfsd: have nfsd_test_lock use the nfsd_file cache nfsd: hook up nfs4_preprocess_stateid_op to the nfsd_file cache ...
2019-09-26Merge tag 'nfs-for-5.4-1' of git://git.linux-nfs.org/projects/anna/linux-nfsLinus Torvalds
Pull NFS client updates from Anna Schumaker: "Stable bugfixes: - Dequeue the request from the receive queue while we're re-encoding # v4.20+ - Fix buffer handling of GSS MIC without slack # 5.1 Features: - Increase xprtrdma maximum transport header and slot table sizes - Add support for nfs4_call_sync() calls using a custom rpc_task_struct - Optimize the default readahead size - Enable pNFS filelayout LAYOUTGET on OPEN Other bugfixes and cleanups: - Fix possible null-pointer dereferences and memory leaks - Various NFS over RDMA cleanups - Various NFS over RDMA comment updates - Don't receive TCP data into a reset request buffer - Don't try to parse incomplete RPC messages - Fix congestion window race with disconnect - Clean up pNFS return-on-close error handling - Fixes for NFS4ERR_OLD_STATEID handling" * tag 'nfs-for-5.4-1' of git://git.linux-nfs.org/projects/anna/linux-nfs: (53 commits) pNFS/filelayout: enable LAYOUTGET on OPEN NFS: Optimise the default readahead size NFSv4: Handle NFS4ERR_OLD_STATEID in LOCKU NFSv4: Handle NFS4ERR_OLD_STATEID in CLOSE/OPEN_DOWNGRADE NFSv4: Fix OPEN_DOWNGRADE error handling pNFS: Handle NFS4ERR_OLD_STATEID on layoutreturn by bumping the state seqid NFSv4: Add a helper to increment stateid seqids NFSv4: Handle RPC level errors in LAYOUTRETURN NFSv4: Handle NFS4ERR_DELAY correctly in return-on-close NFSv4: Clean up pNFS return-on-close error handling pNFS: Ensure we do clear the return-on-close layout stateid on fatal errors NFS: remove unused check for negative dentry NFSv3: use nfs_add_or_obtain() to create and reference inodes NFS: Refactor nfs_instantiate() for dentry referencing callers SUNRPC: Fix congestion window race with disconnect SUNRPC: Don't try to parse incomplete RPC messages SUNRPC: Rename xdr_buf_read_netobj to xdr_buf_read_mic SUNRPC: Fix buffer handling of GSS MIC without slack SUNRPC: RPC level errors should always set task->tk_rpc_status SUNRPC: Don't receive TCP data into a request buffer that has been reset ...
2019-09-25sunrpc: clean up indentation issueColin Ian King
There are statements that are indented incorrectly, remove the extraneous spacing. Signed-off-by: Colin Ian King <colin.king@canonical.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2019-09-21Merge tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdmaLinus Torvalds
Pull RDMA subsystem updates from Jason Gunthorpe: "This cycle mainly saw lots of bug fixes and clean up code across the core code and several drivers, few new functional changes were made. - Many cleanup and bug fixes for hns - Various small bug fixes and cleanups in hfi1, mlx5, usnic, qed, bnxt_re, efa - Share the query_port code between all the iWarp drivers - General rework and cleanup of the ODP MR umem code to fit better with the mmu notifier get/put scheme - Support rdma netlink in non init_net name spaces - mlx5 support for XRC devx and DC ODP" * tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma: (99 commits) RDMA: Fix double-free in srq creation error flow RDMA/efa: Fix incorrect error print IB/mlx5: Free mpi in mp_slave mode IB/mlx5: Use the original address for the page during free_pages RDMA/bnxt_re: Fix spelling mistake "missin_resp" -> "missing_resp" RDMA/hns: Package operations of rq inline buffer into separate functions RDMA/hns: Optimize cmd init and mode selection for hip08 IB/hfi1: Define variables as unsigned long to fix KASAN warning IB/{rdmavt, hfi1, qib}: Add a counter for credit waits IB/hfi1: Add traces for TID RDMA READ RDMA/siw: Relax from kmap_atomic() use in TX path IB/iser: Support up to 16MB data transfer in a single command RDMA/siw: Fix page address mapping in TX path RDMA: Fix goto target to release the allocated memory RDMA/usnic: Avoid overly large buffers on stack RDMA/odp: Add missing cast for 32 bit RDMA/hns: Use devm_platform_ioremap_resource() to simplify code Documentation/infiniband: update name of some functions RDMA/cma: Fix false error message RDMA/hns: Fix wrong assignment of qp_access_flags ...
2019-09-20SUNRPC: Fix congestion window race with disconnectChuck Lever
If the congestion window closes just as the transport disconnects, a reconnect is never driven because: 1. The XPRT_CONG_WAIT flag prevents tasks from taking the write lock 2. There's no wake-up of the first task on the xprt->sending queue To address this, clear the congestion wait flag as part of completing a disconnect. Fixes: 75891f502f5f ("SUNRPC: Support for congestion control ... ") Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-09-20SUNRPC: Don't try to parse incomplete RPC messagesTrond Myklebust
If the copy of the RPC reply into our buffers did not complete, and we could end up with a truncated message. In that case, just resend the call. Fixes: a0584ee9aed80 ("SUNRPC: Use struct xdr_stream when decoding...") Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-09-20SUNRPC: Rename xdr_buf_read_netobj to xdr_buf_read_micBenjamin Coddington
Let the name reflect the single use. The function now assumes the GSS MIC is the last object in the buffer. Signed-off-by: Benjamin Coddington <bcodding@redhat.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-09-20SUNRPC: Fix buffer handling of GSS MIC without slackBenjamin Coddington
The GSS Message Integrity Check data for krb5i may lie partially in the XDR reply buffer's pages and tail. If so, we try to copy the entire MIC into free space in the tail. But as the estimations of the slack space required for authentication and verification have improved there may be less free space in the tail to complete this copy -- see commit 2c94b8eca1a2 ("SUNRPC: Use au_rslack when computing reply buffer size"). In fact, there may only be room in the tail for a single copy of the MIC, and not part of the MIC and then another complete copy. The real world failure reported is that `ls` of a directory on NFS may sometimes return -EIO, which can be traced back to xdr_buf_read_netobj() failing to find available free space in the tail to copy the MIC. Fix this by checking for the case of the MIC crossing the boundaries of head, pages, and tail. If so, shift the buffer until the MIC is contained completely within the pages or tail. This allows the remainder of the function to create a sub buffer that directly address the complete MIC. Signed-off-by: Benjamin Coddington <bcodding@redhat.com> Cc: stable@vger.kernel.org # v5.1 Reviewed-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-09-18Merge branch 'work.mount-base' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull vfs mount API infrastructure updates from Al Viro: "Infrastructure bits of mount API conversions. The rest is more of per-filesystem updates and that will happen in separate pull requests" * 'work.mount-base' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: mtd: Provide fs_context-aware mount_mtd() replacement vfs: Create fs_context-aware mount_bdev() replacement new helper: get_tree_keyed() vfs: set fs_context::user_ns for reconfigure
2019-09-17SUNRPC: RPC level errors should always set task->tk_rpc_statusTrond Myklebust
Ensure that we set task->tk_rpc_status for all RPC level errors so that the caller can distinguish between those and server reply status errors. Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-09-17SUNRPC: Don't receive TCP data into a request buffer that has been resetTrond Myklebust
If we've removed the request from the receive list, and have added it back after resetting the request receive buffer, then we should only receive message data if it is a new reply (i.e. if transport->recv.copied is zero). Fixes: 277e4ab7d530b ("SUNRPC: Simplify TCP receive code by switching...") Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-09-17SUNRPC: Dequeue the request from the receive queue while we're re-encodingTrond Myklebust
Ensure that we dequeue the request from the transport receive queue while we're re-encoding to prevent issues like use-after-free when we release the bvec. Fixes: 7536908982047 ("SUNRPC: Ensure the bvecs are reset when we re-encode...") Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Cc: stable@vger.kernel.org # v4.20+ Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-09-13Merge tag 'v5.3-rc8' into rdma.git for-nextJason Gunthorpe
To resolve dependencies in following patches mlx5_ib.h conflict resolved by keeing both hunks Linux 5.3-rc8 Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2019-09-05new helper: get_tree_keyed()Al Viro
For vfs_get_keyed_super users. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2019-09-05sunrpc: Use kzfree rather than its implementation.zhong jiang
Use kzfree instead of memset() + kfree(). Signed-off-by: zhong jiang <zhongjiang@huawei.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-08-26xprtrdma: Send Queue size grows after a reconnectChuck Lever
Eli Dorfman reports that after a series of idle disconnects, an RPC/RDMA transport becomes unusable (rdma_create_qp returns -ENOMEM). Problem was tracked down to increasing Send Queue size after each reconnect. The rdma_create_qp() API does not promise to leave its @qp_init_attr parameter unaltered. In fact, some drivers do modify one or more of its fields. Thus our calls to rdma_create_qp must use a fresh copy of ib_qp_init_attr each time. This fix is appropriate for kernels dating back to late 2007, though it will have to be adapted, as the connect code has changed over the years. Reported-by: Eli Dorfman <eli@vastdata.com> Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-08-26xprtrdma: Clear xprt->reestablish_timeout on closeChuck Lever
Ensure that the re-establishment delay does not grow exponentially on each good reconnect. This probably should have been part of commit 675dd90ad093 ("xprtrdma: Modernize ops->connect"). Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-08-26SUNRPC: Handle connection breakages correctly in call_status()Trond Myklebust
If the connection breaks while we're waiting for a reply from the server, then we want to immediately try to reconnect. Fixes: ec6017d90359 ("SUNRPC fix regression in umount of a secure mount") Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2019-08-26Revert "NFSv4/flexfiles: Abort I/O early if the layout segment was invalidated"Trond Myklebust
This reverts commit a79f194aa4879e9baad118c3f8bb2ca24dbef765. The mechanism for aborting I/O is racy, since we are not guaranteed that the request is asleep while we're changing both task->tk_status and task->tk_action. Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Cc: stable@vger.kernel.org # v5.1
2019-08-26SUNRPC: Handle EADDRINUSE and ENOBUFS correctlyTrond Myklebust
If a connect or bind attempt returns EADDRINUSE, that means we want to retry with a different port. It is not a fatal connection error. Similarly, ENOBUFS is not fatal, but just indicates a memory allocation issue. Retry after a short delay. Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2019-08-26SUNRPC: Don't handle errors if the bind/connect succeededTrond Myklebust
Don't handle errors in call_bind_status()/call_connect_status() if it turns out that a previous call caused it to succeed. Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Cc: stable@vger.kernel.org # v5.1+
2019-08-26xprtrdma: Recycle MRs after disconnectChuck Lever
The optimization done in "xprtrdma: Simplify rpcrdma_mr_pop" was a bit too optimistic. MRs left over after a reconnect still need to be recycled, not added back to the free list, since they could be in flight or actually fully registered. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-08-21xprtrdma: Optimize rpcrdma_post_recvs()Chuck Lever
Micro-optimization: In rpcrdma_post_recvs, since commit e340c2d6ef2a ("xprtrdma: Reduce the doorbell rate (Receive)"), the common case is to return without doing anything. Found with perf. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-08-21xprtrdma: Inline XDR chunk encoder functionsChuck Lever
Micro-optimization: Save the cost of three function calls during transport header encoding. These were "noinline" before to generate more meaningful call stacks during debugging, but this code is now pretty stable. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-08-21xprtrdma: Fix bc_max_slots return valueChuck Lever
For the moment the returned value just happens to be correct because the current backchannel server implementation does not vary the number of credits it offers. The spec does permit this value to change during the lifetime of a connection, however. The actual maximum is fixed for all RPC/RDMA transports, because each transport instance has to pre-allocate the resources for processing BC requests. That's the value that should be returned. Fixes: 7402a4fedc2b ("SUNRPC: Fix up backchannel slot table ... ") Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-08-21xprtrdma: Clean up xprt_rdma_set_connect_timeout()Chuck Lever
Clean up: The function name should match the documenting comment. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-08-21xprtrdma: Use an llist to manage free rpcrdma_repsChuck Lever
rpcrdma_rep objects are removed from their free list by only a single thread: the Receive completion handler. Thus that free list can be converted to an llist, where a single-threaded consumer and a multi-threaded producer (rpcrdma_buffer_put) can both access the llist without the need for any serialization. This eliminates spin lock contention between the Receive completion handler and rpcrdma_buffer_get, and makes the rep consumer wait- free. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-08-21xprtrdma: Remove rpcrdma_buffer::rb_mrlockChuck Lever
Clean up: Now that the free list is used sparingly, get rid of the separate spin lock protecting it. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-08-21xprtrdma: Cache free MRs in each rpcrdma_reqChuck Lever
Instead of a globally-contended MR free list, cache MRs in each rpcrdma_req as they are released. This means acquiring and releasing an MR will be lock-free in the common case, even outside the transport send lock. The original idea of per-rpcrdma_req MR free lists was suggested by Shirley Ma <shirley.ma@oracle.com> several years ago. I just now figured out how to make that idea work with on-demand MR allocation. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-08-20xprtrdma: Ensure creating an MR does not trigger FS writebackChuck Lever
Probably would be good to also pass GFP flags to ib_alloc_mr. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-08-20xprtrdma: Move rpcrdma_mr_get out of frwr_mapChuck Lever
Refactor: Retrieve an MR and handle error recovery entirely in rpc_rdma.c, as this is not a device-specific function. Note that since commit 89f90fe1ad8b ("SUNRPC: Allow calls to xprt_transmit() to drain the entire transmit queue"), the xprt_transmit function handles the cond_resched. The transport no longer has to do this itself. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-08-20xprtrdma: Combine rpcrdma_mr_put and rpcrdma_mr_unmap_and_putChuck Lever
Clean up. There is only one remaining rpcrdma_mr_put call site, and it can be directly replaced with unmap_and_put because mr->mr_dir is set to DMA_NONE just before the call. Now all the call sites do a DMA unmap, and we can just rename mr_unmap_and_put to mr_put, which nicely matches mr_get. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-08-20xprtrdma: Simplify rpcrdma_mr_popChuck Lever
Clean up: rpcrdma_mr_pop call sites check if the list is empty first. Let's replace the list_empty with less costly logic. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-08-20xprtrdma: Toggle XPRT_CONGESTED in xprtrdma's slot methodsChuck Lever
Commit 48be539dd44a ("xprtrdma: Introduce ->alloc_slot call-out for xprtrdma") added a separate alloc_slot and free_slot to the RPC/RDMA transport. Later, commit 75891f502f5f ("SUNRPC: Support for congestion control when queuing is enabled") modified the generic alloc/free_slot methods, but neglected the methods in xprtrdma. Found via code review. Fixes: 75891f502f5f ("SUNRPC: Support for congestion control ... ") Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-08-20xprtrdma: Rename rpcrdma_buffer::rb_allChuck Lever
Clean up: There are other "all" list heads. For code clarity distinguish this one as for use only for MRs by renaming it. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>