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* Revert "rxrpc: Allow failed client calls to be retried"David Howells2019-01-161-7/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The changes introduced to allow rxrpc calls to be retried creates an issue when it comes to refcounting afs_call structs. The problem is that when rxrpc_send_data() queues the last packet for an asynchronous call, the following sequence can occur: (1) The notify_end_tx callback is invoked which causes the state in the afs_call to be changed from AFS_CALL_CL_REQUESTING or AFS_CALL_SV_REPLYING. (2) afs_deliver_to_call() can then process event notifications from rxrpc on the async_work queue. (3) Delivery of events, such as an abort from the server, can cause the afs_call state to be changed to AFS_CALL_COMPLETE on async_work. (4) For an asynchronous call, afs_process_async_call() notes that the call is complete and tried to clean up all the refs on async_work. (5) rxrpc_send_data() might return the amount of data transferred (success) or an error - which could in turn reflect a local error or a received error. Synchronising the clean up after rxrpc_kernel_send_data() returns an error with the asynchronous cleanup is then tricky to get right. Mostly revert commit c038a58ccfd6704d4d7d60ed3d6a0fca13cf13a4. The two API functions the original commit added aren't currently used. This makes rxrpc_kernel_send_data() always return successfully if it queued the data it was given. Note that this doesn't affect synchronous calls since their Rx notification function merely pokes a wait queue and does not refcounting. The asynchronous call notification function *has* to do refcounting and pass a ref over the work item to avoid the need to sync the workqueue in call cleanup. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* rxrpc: Fix lockup due to no error backoff after ack transmit errorDavid Howells2018-11-031-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If the network becomes (partially) unavailable, say by disabling IPv6, the background ACK transmission routine can get itself into a tizzy by proposing immediate ACK retransmission. Since we're in the call event processor, that happens immediately without returning to the workqueue manager. The condition should clear after a while when either the network comes back or the call times out. Fix this by: (1) When re-proposing an ACK on failed Tx, don't schedule it immediately. This will allow a certain amount of time to elapse before we try again. (2) Enforce a return to the workqueue manager after a certain number of iterations of the call processing loop. (3) Add a backoff delay that increases the delay on deferred ACKs by a jiffy per failed transmission to a limit of HZ. The backoff delay is cleared on a successful return from kernel_sendmsg(). (4) Cancel calls immediately if the opening sendmsg fails. The layer above can arrange retransmission or rotate to another server. Fixes: 248f219cb8bc ("rxrpc: Rewrite the data and ack handling code") Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* Merge branch 'linus' of ↵Linus Torvalds2018-10-261-1/+1
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 Pull crypto updates from Herbert Xu: "API: - Remove VLA usage - Add cryptostat user-space interface - Add notifier for new crypto algorithms Algorithms: - Add OFB mode - Remove speck Drivers: - Remove x86/sha*-mb as they are buggy - Remove pcbc(aes) from x86/aesni - Improve performance of arm/ghash-ce by up to 85% - Implement CTS-CBC in arm64/aes-blk, faster by up to 50% - Remove PMULL based arm64/crc32 driver - Use PMULL in arm64/crct10dif - Add aes-ctr support in s5p-sss - Add caam/qi2 driver Others: - Pick better transform if one becomes available in crc-t10dif" * 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (124 commits) crypto: chelsio - Update ntx queue received from cxgb4 crypto: ccree - avoid implicit enum conversion crypto: caam - add SPDX license identifier to all files crypto: caam/qi - simplify CGR allocation, freeing crypto: mxs-dcp - make symbols 'sha1_null_hash' and 'sha256_null_hash' static crypto: arm64/aes-blk - ensure XTS mask is always loaded crypto: testmgr - fix sizeof() on COMP_BUF_SIZE crypto: chtls - remove set but not used variable 'csk' crypto: axis - fix platform_no_drv_owner.cocci warnings crypto: x86/aes-ni - fix build error following fpu template removal crypto: arm64/aes - fix handling sub-block CTS-CBC inputs crypto: caam/qi2 - avoid double export crypto: mxs-dcp - Fix AES issues crypto: mxs-dcp - Fix SHA null hashes and output length crypto: mxs-dcp - Implement sha import/export crypto: aegis/generic - fix for big endian systems crypto: morus/generic - fix for big endian systems crypto: lrw - fix rebase error after out of bounds fix crypto: cavium/nitrox - use pci_alloc_irq_vectors() while enabling MSI-X. crypto: cavium/nitrox - NITROX command queue changes. ...
| * rxrpc: Remove VLA usage of skcipherKees Cook2018-09-281-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | In the quest to remove all stack VLA usage from the kernel[1], this replaces struct crypto_skcipher and SKCIPHER_REQUEST_ON_STACK() usage with struct crypto_sync_skcipher and SYNC_SKCIPHER_REQUEST_ON_STACK(), which uses a fixed stack size. [1] https://lkml.kernel.org/r/CA+55aFzCG-zNmZwX4A2FQpadafLfEzK6CC=qPXydAacU1RqZWA@mail.gmail.com Cc: David Howells <dhowells@redhat.com> Cc: linux-afs@lists.infradead.org Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
* | rxrpc: Add /proc/net/rxrpc/peers to display peer listDavid Howells2018-10-161-0/+1
| | | | | | | | | | | | | | Add /proc/net/rxrpc/peers to display the list of peers currently active. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller2018-10-131-10/+13
|\ \ | | | | | | | | | | | | | | | | | | | | | Conflicts were easy to resolve using immediate context mostly, except the cls_u32.c one where I simply too the entire HEAD chunk. Signed-off-by: David S. Miller <davem@davemloft.net>
| * | rxrpc: Fix the packet reception routineDavid Howells2018-10-081-3/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The rxrpc_input_packet() function and its call tree was built around the assumption that data_ready() handler called from UDP to inform a kernel service that there is data to be had was non-reentrant. This means that certain locking could be dispensed with. This, however, turns out not to be the case with a multi-queue network card that can deliver packets to multiple cpus simultaneously. Each of those cpus can be in the rxrpc_input_packet() function at the same time. Fix by adding or changing some structure members: (1) Add peer->rtt_input_lock to serialise access to the RTT buffer. (2) Make conn->service_id into a 32-bit variable so that it can be cmpxchg'd on all arches. (3) Add call->input_lock to serialise access to the Rx/Tx state. Note that although the Rx and Tx states are (almost) entirely separate, there's no point completing the separation and having separate locks since it's a bi-phasal RPC protocol rather than a bi-direction streaming protocol. Data transmission and data reception do not take place simultaneously on any particular call. and making the following functional changes: (1) In rxrpc_input_data(), hold call->input_lock around the core to prevent simultaneous producing of packets into the Rx ring and updating of tracking state for a particular call. (2) In rxrpc_input_ping_response(), only read call->ping_serial once, and check it before checking RXRPC_CALL_PINGING as that's a cheaper test. The bit test and bit clear can then be combined. No further locking is needed here. (3) In rxrpc_input_ack(), take call->input_lock after we've parsed much of the ACK packet. The superseded ACK check is then done both before and after the lock is taken. The handing of ackinfo data is split, parsing before the lock is taken and processing with it held. This is keyed on rxMTU being non-zero. Congestion management is also done within the locked section. (4) In rxrpc_input_ackall(), take call->input_lock around the Tx window rotation. The ACKALL packet carries no information and is only really useful after all packets have been transmitted since it's imprecise. (5) In rxrpc_input_implicit_end_call(), we use rx->incoming_lock to prevent calls being simultaneously implicitly ended on two cpus and also to prevent any races with incoming call setup. (6) In rxrpc_input_packet(), use cmpxchg() to effect the service upgrade on a connection. It is only permitted to happen once for a connection. (7) In rxrpc_new_incoming_call(), we have to recheck the routing inside rx->incoming_lock to see if someone else set up the call, connection or peer whilst we were getting there. We can't trust the values from the earlier routing check unless we pin refs on them - which we want to avoid. Further, we need to allow for an incoming call to have its state changed on another CPU between us making it live and us adjusting it because the conn is now in the RXRPC_CONN_SERVICE state. (8) In rxrpc_peer_add_rtt(), take peer->rtt_input_lock around the access to the RTT buffer. Don't need to lock around setting peer->rtt. For reference, the inventory of state-accessing or state-altering functions used by the packet input procedure is: > rxrpc_input_packet() * PACKET CHECKING * ROUTING > rxrpc_post_packet_to_local() > rxrpc_find_connection_rcu() - uses RCU > rxrpc_lookup_peer_rcu() - uses RCU > rxrpc_find_service_conn_rcu() - uses RCU > idr_find() - uses RCU * CONNECTION-LEVEL PROCESSING - Service upgrade - Can only happen once per conn ! Changed to use cmpxchg > rxrpc_post_packet_to_conn() - Setting conn->hi_serial - Probably safe not using locks - Maybe use cmpxchg * CALL-LEVEL PROCESSING > Old-call checking > rxrpc_input_implicit_end_call() > rxrpc_call_completed() > rxrpc_queue_call() ! Need to take rx->incoming_lock > __rxrpc_disconnect_call() > rxrpc_notify_socket() > rxrpc_new_incoming_call() - Uses rx->incoming_lock for the entire process - Might be able to drop this earlier in favour of the call lock > rxrpc_incoming_call() ! Conflicts with rxrpc_input_implicit_end_call() > rxrpc_send_ping() - Don't need locks to check rtt state > rxrpc_propose_ACK * PACKET DISTRIBUTION > rxrpc_input_call_packet() > rxrpc_input_data() * QUEUE DATA PACKET ON CALL > rxrpc_reduce_call_timer() - Uses timer_reduce() ! Needs call->input_lock() > rxrpc_receiving_reply() ! Needs locking around ack state > rxrpc_rotate_tx_window() > rxrpc_end_tx_phase() > rxrpc_proto_abort() > rxrpc_input_dup_data() - Fills the Rx buffer - rxrpc_propose_ACK() - rxrpc_notify_socket() > rxrpc_input_ack() * APPLY ACK PACKET TO CALL AND DISCARD PACKET > rxrpc_input_ping_response() - Probably doesn't need any extra locking ! Need READ_ONCE() on call->ping_serial > rxrpc_input_check_for_lost_ack() - Takes call->lock to consult Tx buffer > rxrpc_peer_add_rtt() ! Needs to take a lock (peer->rtt_input_lock) ! Could perhaps manage with cmpxchg() and xadd() instead > rxrpc_input_requested_ack - Consults Tx buffer ! Probably needs a lock > rxrpc_peer_add_rtt() > rxrpc_propose_ack() > rxrpc_input_ackinfo() - Changes call->tx_winsize ! Use cmpxchg to handle change ! Should perhaps track serial number - Uses peer->lock to record MTU specification changes > rxrpc_proto_abort() ! Need to take call->input_lock > rxrpc_rotate_tx_window() > rxrpc_end_tx_phase() > rxrpc_input_soft_acks() - Consults the Tx buffer > rxrpc_congestion_management() - Modifies the Tx annotations ! Needs call->input_lock() > rxrpc_queue_call() > rxrpc_input_abort() * APPLY ABORT PACKET TO CALL AND DISCARD PACKET > rxrpc_set_call_completion() > rxrpc_notify_socket() > rxrpc_input_ackall() * APPLY ACKALL PACKET TO CALL AND DISCARD PACKET ! Need to take call->input_lock > rxrpc_rotate_tx_window() > rxrpc_end_tx_phase() > rxrpc_reject_packet() There are some functions used by the above that queue the packet, after which the procedure is terminated: - rxrpc_post_packet_to_local() - local->event_queue is an sk_buff_head - local->processor is a work_struct - rxrpc_post_packet_to_conn() - conn->rx_queue is an sk_buff_head - conn->processor is a work_struct - rxrpc_reject_packet() - local->reject_queue is an sk_buff_head - local->processor is a work_struct And some that offload processing to process context: - rxrpc_notify_socket() - Uses RCU lock - Uses call->notify_lock to call call->notify_rx - Uses call->recvmsg_lock to queue recvmsg side - rxrpc_queue_call() - call->processor is a work_struct - rxrpc_propose_ACK() - Uses call->lock to wrap __rxrpc_propose_ACK() And a bunch that complete a call, all of which use call->state_lock to protect the call state: - rxrpc_call_completed() - rxrpc_set_call_completion() - rxrpc_abort_call() - rxrpc_proto_abort() - Also uses rxrpc_queue_call() Fixes: 17926a79320a ("[AF_RXRPC]: Provide secure RxRPC sockets for use by userspace and kernel both") Signed-off-by: David Howells <dhowells@redhat.com>
| * | rxrpc: Fix connection-level abort handlingDavid Howells2018-10-081-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fix connection-level abort handling to cache the abort and error codes properly so that a new incoming call can be properly aborted if it races with the parent connection being aborted by another CPU. The abort_code and error parameters can then be dropped from rxrpc_abort_calls(). Fixes: f5c17aaeb2ae ("rxrpc: Calls should only have one terminal state") Signed-off-by: David Howells <dhowells@redhat.com>
| * | rxrpc: Use the UDP encap_rcv hookDavid Howells2018-10-081-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Use the UDP encap_rcv hook to cut the bit out of the rxrpc packet reception in which a packet is placed onto the UDP receive queue and then immediately removed again by rxrpc. Going via the queue in this manner seems like it should be unnecessary. This does, however, require the invention of a value to place in encap_type as that's one of the conditions to switch packets out to the encap_rcv hook. Possibly the value doesn't actually matter for anything other than sockopts on the UDP socket, which aren't accessible outside of rxrpc anyway. This seems to cut a bit of time out of the time elapsed between each sk_buff being timestamped and turning up in rxrpc (the final number in the following trace excerpts). I measured this by making the rxrpc_rx_packet trace point print the time elapsed between the skb being timestamped and the current time (in ns), e.g.: ... 424.278721: rxrpc_rx_packet: ... ACK 25026 So doing a 512MiB DIO read from my test server, with an unmodified kernel: N min max sum mean stddev 27605 2626 7581 7.83992e+07 2840.04 181.029 and with the patch applied: N min max sum mean stddev 27547 1895 12165 6.77461e+07 2459.29 255.02 Signed-off-by: David Howells <dhowells@redhat.com>
| * | rxrpc: Fix some missed refs to init_netDavid Howells2018-10-051-4/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | Fix some refs to init_net that should've been changed to the appropriate network namespace. Fixes: 2baec2c3f854 ("rxrpc: Support network namespacing") Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Paolo Abeni <pabeni@redhat.com>
* | | rxrpc: Drop the local endpoint arg from rxrpc_extract_addr_from_skb()David Howells2018-10-041-2/+1
| | | | | | | | | | | | | | | | | | | | | rxrpc_extract_addr_from_skb() doesn't use the argument that points to the local endpoint, so remove the argument. Signed-off-by: David Howells <dhowells@redhat.com>
* | | rxrpc: Use rxrpc_free_skb() rather than rxrpc_lose_skb() David Howells2018-10-041-1/+0
|/ / | | | | | | | | | | | | rxrpc_lose_skb() is now exactly the same as rxrpc_free_skb(), so remove it and use the latter instead. Signed-off-by: David Howells <dhowells@redhat.com>
* | rxrpc: Fix error distributionDavid Howells2018-09-281-5/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fix error distribution by immediately delivering the errors to all the affected calls rather than deferring them to a worker thread. The problem with the latter is that retries and things can happen in the meantime when we want to stop that sooner. To this end: (1) Stop the error distributor from removing calls from the error_targets list so that peer->lock isn't needed to synchronise against other adds and removals. (2) Require the peer's error_targets list to be accessed with RCU, thereby avoiding the need to take peer->lock over distribution. (3) Don't attempt to affect a call's state if it is already marked complete. Signed-off-by: David Howells <dhowells@redhat.com>
* | rxrpc: Make service call handling more robustDavid Howells2018-09-281-3/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Make the following changes to improve the robustness of the code that sets up a new service call: (1) Cache the rxrpc_sock struct obtained in rxrpc_data_ready() to do a service ID check and pass that along to rxrpc_new_incoming_call(). This means that I can remove the check from rxrpc_new_incoming_call() without the need to worry about the socket attached to the local endpoint getting replaced - which would invalidate the check. (2) Cache the rxrpc_peer struct, thereby allowing the peer search to be done once. The peer is passed to rxrpc_new_incoming_call(), thereby saving the need to repeat the search. This also reduces the possibility of rxrpc_publish_service_conn() BUG()'ing due to the detection of a duplicate connection, despite the initial search done by rxrpc_find_connection_rcu() having turned up nothing. This BUG() shouldn't ever get hit since rxrpc_data_ready() *should* be non-reentrant and the result of the initial search should still hold true, but it has proven possible to hit. I *think* this may be due to __rxrpc_lookup_peer_rcu() cutting short the iteration over the hash table if it finds a matching peer with a zero usage count, but I don't know for sure since it's only ever been hit once that I know of. Another possibility is that a bug in rxrpc_data_ready() that checked the wrong byte in the header for the RXRPC_CLIENT_INITIATED flag might've let through a packet that caused a spurious and invalid call to be set up. That is addressed in another patch. (3) Fix __rxrpc_lookup_peer_rcu() to skip peer records that have a zero usage count rather than stopping and returning not found, just in case there's another peer record behind it in the bucket. (4) Don't search the peer records in rxrpc_alloc_incoming_call(), but rather either use the peer cached in (2) or, if one wasn't found, preemptively install a new one. Fixes: 8496af50eb38 ("rxrpc: Use RCU to access a peer's service connection tree") Signed-off-by: David Howells <dhowells@redhat.com>
* | rxrpc: Emit BUSY packets when supposed to rather than ABORTsDavid Howells2018-09-281-9/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In the input path, a received sk_buff can be marked for rejection by setting RXRPC_SKB_MARK_* in skb->mark and, if needed, some auxiliary data (such as an abort code) in skb->priority. The rejection is handled by queueing the sk_buff up for dealing with in process context. The output code reads the mark and priority and, theoretically, generates an appropriate response packet. However, if RXRPC_SKB_MARK_BUSY is set, this isn't noticed and an ABORT message with a random abort code is generated (since skb->priority wasn't set to anything). Fix this by outputting the appropriate sort of packet. Also, whilst we're at it, most of the marks are no longer used, so remove them and rename the remaining two to something more obvious. Fixes: 248f219cb8bc ("rxrpc: Rewrite the data and ack handling code") Signed-off-by: David Howells <dhowells@redhat.com>
* | rxrpc: Fix checks as to whether we should set up a new callDavid Howells2018-09-281-0/+10
|/ | | | | | | | | | | There's a check in rxrpc_data_ready() that's checking the CLIENT_INITIATED flag in the packet type field rather than in the packet flags field. Fix this by creating a pair of helper functions to check whether the packet is going to the client or to the server and use them generally. Fixes: 248f219cb8bc ("rxrpc: Rewrite the data and ack handling code") Signed-off-by: David Howells <dhowells@redhat.com>
* Merge ra.kernel.org:/pub/scm/linux/kernel/git/davem/netDavid S. Miller2018-08-091-4/+4
|\ | | | | | | | | | | | | Overlapping changes in RXRPC, changing to ktime_get_seconds() whilst adding some tracepoints. Signed-off-by: David S. Miller <davem@davemloft.net>
| * rxrpc: Fix the keepalive generator [ver #2]David Howells2018-08-091-4/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | AF_RXRPC has a keepalive message generator that generates a message for a peer ~20s after the last transmission to that peer to keep firewall ports open. The implementation is incorrect in the following ways: (1) It mixes up ktime_t and time64_t types. (2) It uses ktime_get_real(), the output of which may jump forward or backward due to adjustments to the time of day. (3) If the current time jumps forward too much or jumps backwards, the generator function will crank the base of the time ring round one slot at a time (ie. a 1s period) until it catches up, spewing out VERSION packets as it goes. Fix the problem by: (1) Only using time64_t. There's no need for sub-second resolution. (2) Use ktime_get_seconds() rather than ktime_get_real() so that time isn't perceived to go backwards. (3) Simplifying rxrpc_peer_keepalive_worker() by splitting it into two parts: (a) The "worker" function that manages the buckets and the timer. (b) The "dispatch" function that takes the pending peers and potentially transmits a keepalive packet before putting them back in the ring into the slot appropriate to the revised last-Tx time. (4) Taking everything that's pending out of the ring and splicing it into a temporary collector list for processing. In the case that there's been a significant jump forward, the ring gets entirely emptied and then the time base can be warped forward before the peers are processed. The warping can't happen if the ring isn't empty because the slot a peer is in is keepalive-time dependent, relative to the base time. (5) Limit the number of iterations of the bucket array when scanning it. (6) Set the timer to skip any empty slots as there's no point waking up if there's nothing to do yet. This can be triggered by an incoming call from a server after a reboot with AF_RXRPC and AFS built into the kernel causing a peer record to be set up before userspace is started. The system clock is then adjusted by userspace, thereby potentially causing the keepalive generator to have a meltdown - which leads to a message like: watchdog: BUG: soft lockup - CPU#0 stuck for 23s! [kworker/0:1:23] ... Workqueue: krxrpcd rxrpc_peer_keepalive_worker EIP: lock_acquire+0x69/0x80 ... Call Trace: ? rxrpc_peer_keepalive_worker+0x5e/0x350 ? _raw_spin_lock_bh+0x29/0x60 ? rxrpc_peer_keepalive_worker+0x5e/0x350 ? rxrpc_peer_keepalive_worker+0x5e/0x350 ? __lock_acquire+0x3d3/0x870 ? process_one_work+0x110/0x340 ? process_one_work+0x166/0x340 ? process_one_work+0x110/0x340 ? worker_thread+0x39/0x3c0 ? kthread+0xdb/0x110 ? cancel_delayed_work+0x90/0x90 ? kthread_stop+0x70/0x70 ? ret_from_fork+0x19/0x24 Fixes: ace45bec6d77 ("rxrpc: Fix firewall route keepalive") Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | rxrpc: Transmit more ACKs during data receptionDavid Howells2018-08-011-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Immediately flush any outstanding ACK on entry to rxrpc_recvmsg_data() - which transfers data to the target buffers - if we previously had an Rx underrun (ie. we returned -EAGAIN because we ran out of received data). This lets the server know what we've managed to receive something. Also flush any outstanding ACK after calling the function if it hit -EAGAIN to let the server know we processed some data. It might be better to send more ACKs, possibly on a time-based scheme, but that needs some more consideration. With this and some additional AFS patches, it is possible to get large unencrypted O_DIRECT reads to be almost as fast as NFS over TCP. It looks like it might be theoretically possible to improve performance yet more for a server running a single operation as investigation of packet timestamps indicates that the server keeps stalling. The issue appears to be that rxrpc runs in to trouble with ACK packets getting batched together (up to ~32 at a time) somewhere between the IP transmit queue on the client and the ethernet receive queue on the server. However, this case isn't too much of a worry as even a lightly loaded server should be receiving sufficient packet flux to flush the ACK packets to the UDP socket. Signed-off-by: David Howells <dhowells@redhat.com>
* | rxrpc: Increase the size of a call's Rx windowDavid Howells2018-08-011-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | Increase the size of a call's Rx window from 32 to 63 - ie. one less than the size of the ring buffer. This makes large data transfers perform better when the Tx window on the other side is around 64 (as is the case with Auristor's YFS fileserver). If the server window size is ~32 or smaller, this should make no difference. Signed-off-by: David Howells <dhowells@redhat.com>
* | rxrpc: Trace packet transmissionDavid Howells2018-08-011-0/+1
|/ | | | | | | | | | | | Trace successful packet transmission (kernel_sendmsg() succeeded, that is) in AF_RXRPC. We can share the enum that defines the transmission points with the trace_rxrpc_tx_fail() tracepoint, so rename its constants to be applicable to both. Also, save the internal call->debug_id in the rxrpc_channel struct so that it can be used in retransmission trace lines. Signed-off-by: David Howells <dhowells@redhat.com>
* Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-nextLinus Torvalds2018-06-071-0/+2
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull networking updates from David Miller: 1) Add Maglev hashing scheduler to IPVS, from Inju Song. 2) Lots of new TC subsystem tests from Roman Mashak. 3) Add TCP zero copy receive and fix delayed acks and autotuning with SO_RCVLOWAT, from Eric Dumazet. 4) Add XDP_REDIRECT support to mlx5 driver, from Jesper Dangaard Brouer. 5) Add ttl inherit support to vxlan, from Hangbin Liu. 6) Properly separate ipv6 routes into their logically independant components. fib6_info for the routing table, and fib6_nh for sets of nexthops, which thus can be shared. From David Ahern. 7) Add bpf_xdp_adjust_tail helper, which can be used to generate ICMP messages from XDP programs. From Nikita V. Shirokov. 8) Lots of long overdue cleanups to the r8169 driver, from Heiner Kallweit. 9) Add BTF ("BPF Type Format"), from Martin KaFai Lau. 10) Add traffic condition monitoring to iwlwifi, from Luca Coelho. 11) Plumb extack down into fib_rules, from Roopa Prabhu. 12) Add Flower classifier offload support to igb, from Vinicius Costa Gomes. 13) Add UDP GSO support, from Willem de Bruijn. 14) Add documentation for eBPF helpers, from Quentin Monnet. 15) Add TLS tx offload to mlx5, from Ilya Lesokhin. 16) Allow applications to be given the number of bytes available to read on a socket via a control message returned from recvmsg(), from Soheil Hassas Yeganeh. 17) Add x86_32 eBPF JIT compiler, from Wang YanQing. 18) Add AF_XDP sockets, with zerocopy support infrastructure as well. From Björn Töpel. 19) Remove indirect load support from all of the BPF JITs and handle these operations in the verifier by translating them into native BPF instead. From Daniel Borkmann. 20) Add GRO support to ipv6 gre tunnels, from Eran Ben Elisha. 21) Allow XDP programs to do lookups in the main kernel routing tables for forwarding. From David Ahern. 22) Allow drivers to store hardware state into an ELF section of kernel dump vmcore files, and use it in cxgb4. From Rahul Lakkireddy. 23) Various RACK and loss detection improvements in TCP, from Yuchung Cheng. 24) Add TCP SACK compression, from Eric Dumazet. 25) Add User Mode Helper support and basic bpfilter infrastructure, from Alexei Starovoitov. 26) Support ports and protocol values in RTM_GETROUTE, from Roopa Prabhu. 27) Support bulking in ->ndo_xdp_xmit() API, from Jesper Dangaard Brouer. 28) Add lots of forwarding selftests, from Petr Machata. 29) Add generic network device failover driver, from Sridhar Samudrala. * ra.kernel.org:/pub/scm/linux/kernel/git/davem/net-next: (1959 commits) strparser: Add __strp_unpause and use it in ktls. rxrpc: Fix terminal retransmission connection ID to include the channel net: hns3: Optimize PF CMDQ interrupt switching process net: hns3: Fix for VF mailbox receiving unknown message net: hns3: Fix for VF mailbox cannot receiving PF response bnx2x: use the right constant Revert "net: sched: cls: Fix offloading when ingress dev is vxlan" net: dsa: b53: Fix for brcm tag issue in Cygnus SoC enic: fix UDP rss bits netdev-FAQ: clarify DaveM's position for stable backports rtnetlink: validate attributes in do_setlink() mlxsw: Add extack messages for port_{un, }split failures netdevsim: Add extack error message for devlink reload devlink: Add extack to reload and port_{un, }split operations net: metrics: add proper netlink validation ipmr: fix error path when ipmr_new_table fails ip6mr: only set ip6mr_table from setsockopt when ip6mr_new_table succeeds net: hns3: remove unused hclgevf_cfg_func_mta_filter netfilter: provide udp*_lib_lookup for nf_tproxy qed*: Utilize FW 8.37.2.0 ...
| * rxrpc: Fix handling of call quietly cancelled out on serverDavid Howells2018-06-041-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Sometimes an in-progress call will stop responding on the fileserver when the fileserver quietly cancels the call with an internally marked abort (RX_CALL_DEAD), without sending an ABORT to the client. This causes the client's call to eventually expire from lack of incoming packets directed its way, which currently leads to it being cancelled locally with ETIME. Note that it's not currently clear as to why this happens as it's really hard to reproduce. The rotation policy implement by kAFS, however, doesn't differentiate between ETIME meaning we didn't get any response from the server and ETIME meaning the call got cancelled mid-flow. The latter leads to an oops when fetching data as the rotation partially resets the afs_read descriptor, which can result in a cleared page pointer being dereferenced because that page has already been filled. Handle this by the following means: (1) Set a flag on a call when we receive a packet for it. (2) Store the highest packet serial number so far received for a call (bearing in mind this may wrap). (3) If, when the "not received anything recently" timeout expires on a call, we've received at least one packet for a call and the connection as a whole has received packets more recently than that call, then cancel the call locally with ECONNRESET rather than ETIME. This indicates that the call was definitely in progress on the server. (4) In kAFS, if the rotation algorithm sees ECONNRESET rather than ETIME, don't try the next server, but rather abort the call. This avoids the oops as we don't try to reuse the afs_read struct. Rather, as-yet ungotten pages will be reread at a later data. Also: (5) Add an rxrpc tracepoint to log detection of the call being reset. Without this, I occasionally see an oops like the following: general protection fault: 0000 [#1] SMP PTI ... RIP: 0010:_copy_to_iter+0x204/0x310 RSP: 0018:ffff8800cae0f828 EFLAGS: 00010206 RAX: 0000000000000560 RBX: 0000000000000560 RCX: 0000000000000560 RDX: ffff8800cae0f968 RSI: ffff8800d58b3312 RDI: 0005080000000000 RBP: ffff8800cae0f968 R08: 0000000000000560 R09: ffff8800ca00f400 R10: ffff8800c36f28d4 R11: 00000000000008c4 R12: ffff8800cae0f958 R13: 0000000000000560 R14: ffff8800d58b3312 R15: 0000000000000560 FS: 00007fdaef108080(0000) GS:ffff8800ca680000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fb28a8fa000 CR3: 00000000d2a76002 CR4: 00000000001606e0 Call Trace: skb_copy_datagram_iter+0x14e/0x289 rxrpc_recvmsg_data.isra.0+0x6f3/0xf68 ? trace_buffer_unlock_commit_regs+0x4f/0x89 rxrpc_kernel_recv_data+0x149/0x421 afs_extract_data+0x1e0/0x798 ? afs_wait_for_call_to_complete+0xc9/0x52e afs_deliver_fs_fetch_data+0x33a/0x5ab afs_deliver_to_call+0x1ee/0x5e0 ? afs_wait_for_call_to_complete+0xc9/0x52e afs_wait_for_call_to_complete+0x12b/0x52e ? wake_up_q+0x54/0x54 afs_make_call+0x287/0x462 ? afs_fs_fetch_data+0x3e6/0x3ed ? rcu_read_lock_sched_held+0x5d/0x63 afs_fs_fetch_data+0x3e6/0x3ed afs_fetch_data+0xbb/0x14a afs_readpages+0x317/0x40d __do_page_cache_readahead+0x203/0x2ba ? ondemand_readahead+0x3a7/0x3c1 ondemand_readahead+0x3a7/0x3c1 generic_file_buffered_read+0x18b/0x62f __vfs_read+0xdb/0xfe vfs_read+0xb2/0x137 ksys_read+0x50/0x8c do_syscall_64+0x7d/0x1a0 entry_SYSCALL_64_after_hwframe+0x49/0xbe Note the weird value in RDI which is a result of trying to kmap() a NULL page pointer. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | proc: introduce proc_create_net{,_data}Christoph Hellwig2018-05-161-2/+2
|/ | | | | | | | | Variants of proc_create{,_data} that directly take a struct seq_operations and deal with network namespaces in ->open and ->release. All callers of proc_create + seq_open_net converted over, and seq_{open,release}_net are removed entirely. Signed-off-by: Christoph Hellwig <hch@lst.de>
* rxrpc: Fix missing start of call timeoutDavid Howells2018-05-111-0/+1
| | | | | | | | | | | | | | | | | The expect_rx_by call timeout is supposed to be set when a call is started to indicate that we need to receive a packet by that point. This is currently put back every time we receive a packet, but it isn't started when we first send a packet. Without this, the call may wait forever if the server doesn't deign to reply. Fix this by setting the timeout upon a successful UDP sendmsg call for the first DATA packet. The timeout is initiated only for initial transmission and not for subsequent retries as we don't want the retry mechanism to extend the timeout indefinitely. Fixes: a158bdd3247b ("rxrpc: Fix call timeouts") Reported-by: Marc Dionne <marc.dionne@auristor.com> Signed-off-by: David Howells <dhowells@redhat.com>
* rxrpc: Fix leak of rxrpc_peer objectsDavid Howells2018-03-301-0/+1
| | | | | | | | | | | | | | | When a new client call is requested, an rxrpc_conn_parameters struct object is passed in with a bunch of parameters set, such as the local endpoint to use. A pointer to the target peer record is also placed in there by rxrpc_get_client_conn() - and this is removed if and only if a new connection object is allocated. Thus it leaks if a new connection object isn't allocated. Fix this by putting any peer object attached to the rxrpc_conn_parameters object in the function that allocated it. Fixes: 19ffa01c9c45 ("rxrpc: Use structs to hold connection params and protocol info") Signed-off-by: David Howells <dhowells@redhat.com>
* rxrpc: Add a tracepoint to track rxrpc_peer refcountingDavid Howells2018-03-301-19/+4
| | | | | | Add a tracepoint to track reference counting on the rxrpc_peer struct. Signed-off-by: David Howells <dhowells@redhat.com>
* rxrpc: Fix apparent leak of rxrpc_local objectsDavid Howells2018-03-301-0/+1
| | | | | | | | | | | | | | | | | | | | | rxrpc_local objects cannot be disposed of until all the connections that point to them have been RCU'd as a connection object holds refcount on the local endpoint it is communicating through. Currently, this can cause an assertion failure to occur when a network namespace is destroyed as there's no check that the RCU destructors for the connections have been run before we start trying to destroy local endpoints. The kernel reports: rxrpc: AF_RXRPC: Leaked local 0000000036a41bc1 {5} ------------[ cut here ]------------ kernel BUG at ../net/rxrpc/local_object.c:439! Fix this by keeping a count of the live connections and waiting for it to go to zero at the end of rxrpc_destroy_all_connections(). Fixes: dee46364ce6f ("rxrpc: Add RCU destruction for connections and calls") Signed-off-by: David Howells <dhowells@redhat.com>
* rxrpc: Add a tracepoint to track rxrpc_local refcountingDavid Howells2018-03-301-23/+4
| | | | | | Add a tracepoint to track reference counting on the rxrpc_local struct. Signed-off-by: David Howells <dhowells@redhat.com>
* rxrpc: Fix potential call vs socket/net destruction raceDavid Howells2018-03-301-0/+2
| | | | | | | | | | | | | | | | | | | | | rxrpc_call structs don't pin sockets or network namespaces, but may attempt to access both after their refcount reaches 0 so that they can detach themselves from the network namespace. However, there's no guarantee that the socket still exists at this point (so sock_net(&call->socket->sk) may be invalid) and the namespace may have gone away if the call isn't pinning a peer. Fix this by (a) carrying a net pointer in the rxrpc_call struct and (b) waiting for all calls to be destroyed when the network namespace goes away. This was detected by checker: net/rxrpc/call_object.c:634:57: warning: incorrect type in argument 1 (different address spaces) net/rxrpc/call_object.c:634:57: expected struct sock const *sk net/rxrpc/call_object.c:634:57: got struct sock [noderef] <asn:4>*<noident> Fixes: 2baec2c3f854 ("rxrpc: Support network namespacing") Signed-off-by: David Howells <dhowells@redhat.com>
* rxrpc: Fix firewall route keepaliveDavid Howells2018-03-301-1/+13
| | | | | | | | | | | | | | Fix the firewall route keepalive part of AF_RXRPC which is currently function incorrectly by replying to VERSION REPLY packets from the server with VERSION REQUEST packets. Instead, send VERSION REPLY packets to the peers of service connections to act as keep-alives 20s after the latest packet was transmitted to that peer. Also, just discard VERSION REPLY packets rather than replying to them. Signed-off-by: David Howells <dhowells@redhat.com>
* rxrpc: Trace call completionDavid Howells2018-03-281-0/+1
| | | | | | | Add a tracepoint to track rxrpc calls moving into the completed state and to log the completion type and the recorded error value and abort code. Signed-off-by: David Howells <dhowells@redhat.com>
* rxrpc, afs: Use debug_ids rather than pointers in tracesDavid Howells2018-03-281-4/+4
| | | | | | | | | | | | | | In rxrpc and afs, use the debug_ids that are monotonically allocated to various objects as they're allocated rather than pointers as kernel pointers are now hashed making them less useful. Further, the debug ids aren't reused anywhere nearly as quickly. In addition, allow kernel services that use rxrpc, such as afs, to take numbers from the rxrpc counter, assign them to their own call struct and pass them in to rxrpc for both client and service calls so that the trace lines for each will have the same ID tag. Signed-off-by: David Howells <dhowells@redhat.com>
* rxrpc: Fix conn expiry timersDavid Howells2017-11-241-2/+4
| | | | | | | | | | | | | | | | | Fix the rxrpc connection expiry timers so that connections for closed AF_RXRPC sockets get deleted in a more timely fashion, freeing up the transport UDP port much more quickly. (1) Replace the delayed work items with work items plus timers so that timer_reduce() can be used to shorten them and so that the timer doesn't requeue the work item if the net namespace is dead. (2) Don't use queue_delayed_work() as that won't alter the timeout if the timer is already running. (3) Don't rearm the timers if the network namespace is dead. Signed-off-by: David Howells <dhowells@redhat.com>
* rxrpc: Fix service endpoint expiryDavid Howells2017-11-241-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | RxRPC service endpoints expire like they're supposed to by the following means: (1) Mark dead rxrpc_net structs (with ->live) rather than twiddling the global service conn timeout, otherwise the first rxrpc_net struct to die will cause connections on all others to expire immediately from then on. (2) Mark local service endpoints for which the socket has been closed (->service_closed) so that the expiration timeout can be much shortened for service and client connections going through that endpoint. (3) rxrpc_put_service_conn() needs to schedule the reaper when the usage count reaches 1, not 0, as idle conns have a 1 count. (4) The accumulator for the earliest time we might want to schedule for should be initialised to jiffies + MAX_JIFFY_OFFSET, not ULONG_MAX as the comparison functions use signed arithmetic. (5) Simplify the expiration handling, adding the expiration value to the idle timestamp each time rather than keeping track of the time in the past before which the idle timestamp must go to be expired. This is much easier to read. (6) Ignore the timeouts if the net namespace is dead. (7) Restart the service reaper work item rather the client reaper. Signed-off-by: David Howells <dhowells@redhat.com>
* rxrpc: Add keepalive for a callDavid Howells2017-11-241-0/+1
| | | | | | | | | | | | | | | | | | | We need to transmit a packet every so often to act as a keepalive for the peer (which has a timeout from the last time it received a packet) and also to prevent any intervening firewalls from closing the route. Do this by resetting a timer every time we transmit a packet. If the timer ever expires, we transmit a PING ACK packet and thereby also elicit a PING RESPONSE ACK from the other side - which prevents our last-rx timeout from expiring. The timer is set to 1/6 of the last-rx timeout so that we can detect the other side going away if it misses 6 replies in a row. This is particularly necessary for servers where the processing of the service function may take a significant amount of time. Signed-off-by: David Howells <dhowells@redhat.com>
* rxrpc: Add a timeout for detecting lost ACKs/lost DATADavid Howells2017-11-241-1/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | Add an extra timeout that is set/updated when we send a DATA packet that has the request-ack flag set. This allows us to detect if we don't get an ACK in response to the latest flagged packet. The ACK packet is adjudged to have been lost if it doesn't turn up within 2*RTT of the transmission. If the timeout occurs, we schedule the sending of a PING ACK to find out the state of the other side. If a new DATA packet is ready to go sooner, we cancel the sending of the ping and set the request-ack flag on that instead. If we get back a PING-RESPONSE ACK that indicates a lower tx_top than what we had at the time of the ping transmission, we adjudge all the DATA packets sent between the response tx_top and the ping-time tx_top to have been lost and retransmit immediately. Rather than sending a PING ACK, we could just pick a DATA packet and speculatively retransmit that with request-ack set. It should result in either a REQUESTED ACK or a DUPLICATE ACK which we can then use in lieu the a PING-RESPONSE ACK mentioned above. Signed-off-by: David Howells <dhowells@redhat.com>
* rxrpc: Fix call timeoutsDavid Howells2017-11-241-13/+24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fix the rxrpc call expiration timeouts and make them settable from userspace. By analogy with other rx implementations, there should be three timeouts: (1) "Normal timeout" This is set for all calls and is triggered if we haven't received any packets from the peer in a while. It is measured from the last time we received any packet on that call. This is not reset by any connection packets (such as CHALLENGE/RESPONSE packets). If a service operation takes a long time, the server should generate PING ACKs at a duration that's substantially less than the normal timeout so is to keep both sides alive. This is set at 1/6 of normal timeout. (2) "Idle timeout" This is set only for a service call and is triggered if we stop receiving the DATA packets that comprise the request data. It is measured from the last time we received a DATA packet. (3) "Hard timeout" This can be set for a call and specified the maximum lifetime of that call. It should not be specified by default. Some operations (such as volume transfer) take a long time. Allow userspace to set/change the timeouts on a call with sendmsg, using a control message: RXRPC_SET_CALL_TIMEOUTS The data to the message is a number of 32-bit words, not all of which need be given: u32 hard_timeout; /* sec from first packet */ u32 idle_timeout; /* msec from packet Rx */ u32 normal_timeout; /* msec from data Rx */ This can be set in combination with any other sendmsg() that affects a call. Signed-off-by: David Howells <dhowells@redhat.com>
* rxrpc: Split the call params from the operation paramsDavid Howells2017-11-241-1/+30
| | | | | | | | | | | | | | | | When rxrpc_sendmsg() parses the control message buffer, it places the parameters extracted into a structure, but lumps together call parameters (such as user call ID) with operation parameters (such as whether to send data, send an abort or accept a call). Split the call parameters out into their own structure, a copy of which is then embedded in the operation parameters struct. The call parameters struct is then passed down into the places that need it instead of passing the individual parameters. This allows for extra call parameters to be added. Signed-off-by: David Howells <dhowells@redhat.com>
* rxrpc: Delay terminal ACK transmission on a client callDavid Howells2017-11-241-0/+17
| | | | | | | | Delay terminal ACK transmission on a client call by deferring it to the connection processor. This allows it to be skipped if we can send the next call instead, the first DATA packet of which will implicitly ack this call. Signed-off-by: David Howells <dhowells@redhat.com>
* rxrpc: Provide a different lockdep key for call->user_mutex for kernel callsDavid Howells2017-11-241-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Provide a different lockdep key for rxrpc_call::user_mutex when the call is made on a kernel socket, such as by the AFS filesystem. The problem is that lockdep registers a false positive between userspace calling the sendmsg syscall on a user socket where call->user_mutex is held whilst userspace memory is accessed whereas the AFS filesystem may perform operations with mmap_sem held by the caller. In such a case, the following warning is produced. ====================================================== WARNING: possible circular locking dependency detected 4.14.0-fscache+ #243 Tainted: G E ------------------------------------------------------ modpost/16701 is trying to acquire lock: (&vnode->io_lock){+.+.}, at: [<ffffffffa000fc40>] afs_begin_vnode_operation+0x33/0x77 [kafs] but task is already holding lock: (&mm->mmap_sem){++++}, at: [<ffffffff8104376a>] __do_page_fault+0x1ef/0x486 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #3 (&mm->mmap_sem){++++}: __might_fault+0x61/0x89 _copy_from_iter_full+0x40/0x1fa rxrpc_send_data+0x8dc/0xff3 rxrpc_do_sendmsg+0x62f/0x6a1 rxrpc_sendmsg+0x166/0x1b7 sock_sendmsg+0x2d/0x39 ___sys_sendmsg+0x1ad/0x22b __sys_sendmsg+0x41/0x62 do_syscall_64+0x89/0x1be return_from_SYSCALL_64+0x0/0x75 -> #2 (&call->user_mutex){+.+.}: __mutex_lock+0x86/0x7d2 rxrpc_new_client_call+0x378/0x80e rxrpc_kernel_begin_call+0xf3/0x154 afs_make_call+0x195/0x454 [kafs] afs_vl_get_capabilities+0x193/0x198 [kafs] afs_vl_lookup_vldb+0x5f/0x151 [kafs] afs_create_volume+0x2e/0x2f4 [kafs] afs_mount+0x56a/0x8d7 [kafs] mount_fs+0x6a/0x109 vfs_kern_mount+0x67/0x135 do_mount+0x90b/0xb57 SyS_mount+0x72/0x98 do_syscall_64+0x89/0x1be return_from_SYSCALL_64+0x0/0x75 -> #1 (k-sk_lock-AF_RXRPC){+.+.}: lock_sock_nested+0x74/0x8a rxrpc_kernel_begin_call+0x8a/0x154 afs_make_call+0x195/0x454 [kafs] afs_fs_get_capabilities+0x17a/0x17f [kafs] afs_probe_fileserver+0xf7/0x2f0 [kafs] afs_select_fileserver+0x83f/0x903 [kafs] afs_fetch_status+0x89/0x11d [kafs] afs_iget+0x16f/0x4f8 [kafs] afs_mount+0x6c6/0x8d7 [kafs] mount_fs+0x6a/0x109 vfs_kern_mount+0x67/0x135 do_mount+0x90b/0xb57 SyS_mount+0x72/0x98 do_syscall_64+0x89/0x1be return_from_SYSCALL_64+0x0/0x75 -> #0 (&vnode->io_lock){+.+.}: lock_acquire+0x174/0x19f __mutex_lock+0x86/0x7d2 afs_begin_vnode_operation+0x33/0x77 [kafs] afs_fetch_data+0x80/0x12a [kafs] afs_readpages+0x314/0x405 [kafs] __do_page_cache_readahead+0x203/0x2ba filemap_fault+0x179/0x54d __do_fault+0x17/0x60 __handle_mm_fault+0x6d7/0x95c handle_mm_fault+0x24e/0x2a3 __do_page_fault+0x301/0x486 do_page_fault+0x236/0x259 page_fault+0x22/0x30 __clear_user+0x3d/0x60 padzero+0x1c/0x2b load_elf_binary+0x785/0xdc7 search_binary_handler+0x81/0x1ff do_execveat_common.isra.14+0x600/0x888 do_execve+0x1f/0x21 SyS_execve+0x28/0x2f do_syscall_64+0x89/0x1be return_from_SYSCALL_64+0x0/0x75 other info that might help us debug this: Chain exists of: &vnode->io_lock --> &call->user_mutex --> &mm->mmap_sem Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&mm->mmap_sem); lock(&call->user_mutex); lock(&mm->mmap_sem); lock(&vnode->io_lock); *** DEADLOCK *** 1 lock held by modpost/16701: #0: (&mm->mmap_sem){++++}, at: [<ffffffff8104376a>] __do_page_fault+0x1ef/0x486 stack backtrace: CPU: 0 PID: 16701 Comm: modpost Tainted: G E 4.14.0-fscache+ #243 Hardware name: ASUS All Series/H97-PLUS, BIOS 2306 10/09/2014 Call Trace: dump_stack+0x67/0x8e print_circular_bug+0x341/0x34f check_prev_add+0x11f/0x5d4 ? add_lock_to_list.isra.12+0x8b/0x8b ? add_lock_to_list.isra.12+0x8b/0x8b ? __lock_acquire+0xf77/0x10b4 __lock_acquire+0xf77/0x10b4 lock_acquire+0x174/0x19f ? afs_begin_vnode_operation+0x33/0x77 [kafs] __mutex_lock+0x86/0x7d2 ? afs_begin_vnode_operation+0x33/0x77 [kafs] ? afs_begin_vnode_operation+0x33/0x77 [kafs] ? afs_begin_vnode_operation+0x33/0x77 [kafs] afs_begin_vnode_operation+0x33/0x77 [kafs] afs_fetch_data+0x80/0x12a [kafs] afs_readpages+0x314/0x405 [kafs] __do_page_cache_readahead+0x203/0x2ba ? filemap_fault+0x179/0x54d filemap_fault+0x179/0x54d __do_fault+0x17/0x60 __handle_mm_fault+0x6d7/0x95c handle_mm_fault+0x24e/0x2a3 __do_page_fault+0x301/0x486 do_page_fault+0x236/0x259 page_fault+0x22/0x30 RIP: 0010:__clear_user+0x3d/0x60 RSP: 0018:ffff880071e93da0 EFLAGS: 00010202 RAX: 0000000000000000 RBX: 000000000000011c RCX: 000000000000011c RDX: 0000000000000000 RSI: 0000000000000008 RDI: 000000000060f720 RBP: 000000000060f720 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000001 R11: ffff8800b5459b68 R12: ffff8800ce150e00 R13: 000000000060f720 R14: 00000000006127a8 R15: 0000000000000000 padzero+0x1c/0x2b load_elf_binary+0x785/0xdc7 search_binary_handler+0x81/0x1ff do_execveat_common.isra.14+0x600/0x888 do_execve+0x1f/0x21 SyS_execve+0x28/0x2f do_syscall_64+0x89/0x1be entry_SYSCALL64_slow_path+0x25/0x25 RIP: 0033:0x7fdb6009ee07 RSP: 002b:00007fff566d9728 EFLAGS: 00000246 ORIG_RAX: 000000000000003b RAX: ffffffffffffffda RBX: 000055ba57280900 RCX: 00007fdb6009ee07 RDX: 000055ba5727f270 RSI: 000055ba5727cac0 RDI: 000055ba57280900 RBP: 000055ba57280900 R08: 00007fff566d9700 R09: 0000000000000000 R10: 000055ba5727cac0 R11: 0000000000000246 R12: 0000000000000000 R13: 000055ba5727cac0 R14: 000055ba5727f270 R15: 0000000000000000 Signed-off-by: David Howells <dhowells@redhat.com>
* rxrpc: Lock around calling a kernel service Rx notificationDavid Howells2017-11-021-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Place a spinlock around the invocation of call->notify_rx() for a kernel service call and lock again when ending the call and replace the notification pointer with a pointer to a dummy function. This is required because it's possible for rxrpc_notify_socket() to be called after the call has been ended by the kernel service if called from the asynchronous work function rxrpc_process_call(). However, rxrpc_notify_socket() currently only holds the RCU read lock when invoking ->notify_rx(), which means that the afs_call struct would need to be disposed of by call_rcu() rather than by kfree(). But we shouldn't see any notifications from a call after calling rxrpc_kernel_end_call(), so a lock is required in rxrpc code. Without this, we may see the call wait queue as having a corrupt spinlock: BUG: spinlock bad magic on CPU#0, kworker/0:2/1612 general protection fault: 0000 [#1] SMP ... Workqueue: krxrpcd rxrpc_process_call task: ffff88040b83c400 task.stack: ffff88040adfc000 RIP: 0010:spin_bug+0x161/0x18f RSP: 0018:ffff88040adffcc0 EFLAGS: 00010002 RAX: 0000000000000032 RBX: 6b6b6b6b6b6b6b6b RCX: ffffffff81ab16cf RDX: ffff88041fa14c01 RSI: ffff88041fa0ccb8 RDI: ffff88041fa0ccb8 RBP: ffff88040adffcd8 R08: 00000000ffffffff R09: 00000000ffffffff R10: ffff88040adffc60 R11: 000000000000022c R12: ffff88040aca2208 R13: ffffffff81a58114 R14: 0000000000000000 R15: 0000000000000000 .... Call Trace: do_raw_spin_lock+0x1d/0x89 _raw_spin_lock_irqsave+0x3d/0x49 ? __wake_up_common_lock+0x4c/0xa7 __wake_up_common_lock+0x4c/0xa7 ? __lock_is_held+0x47/0x7a __wake_up+0xe/0x10 afs_wake_up_call_waiter+0x11b/0x122 [kafs] rxrpc_notify_socket+0x12b/0x258 rxrpc_process_call+0x18e/0x7d0 process_one_work+0x298/0x4de ? rescuer_thread+0x280/0x280 worker_thread+0x1d1/0x2ae ? rescuer_thread+0x280/0x280 kthread+0x12c/0x134 ? kthread_create_on_node+0x3a/0x3a ret_from_fork+0x27/0x40 In this case, note the corrupt data in EBX. The address of the offending afs_call is in R12, plus the offset to the spinlock. Signed-off-by: David Howells <dhowells@redhat.com>
* rxrpc: Allow failed client calls to be retriedDavid Howells2017-08-291-12/+7
| | | | | | | | | | | | | | | | | | | | | | | | Allow a client call that failed on network error to be retried, provided that the Tx queue still holds DATA packet 1. This allows an operation to be submitted to another server or another address for the same server without having to repackage and re-encrypt the data so far processed. Two new functions are provided: (1) rxrpc_kernel_check_call() - This is used to find out the completion state of a call to guess whether it can be retried and whether it should be retried. (2) rxrpc_kernel_retry_call() - Disconnect the call from its current connection, reset the state and submit it as a new client call to a new address. The new address need not match the previous address. A call may be retried even if all the data hasn't been loaded into it yet; a partially constructed will be retained at the same point it was at when an error condition was detected. msg_data_left() can be used to find out how much data was packaged before the error occurred. Signed-off-by: David Howells <dhowells@redhat.com>
* rxrpc: Fix IPv6 supportDavid Howells2017-08-291-2/+2
| | | | | | | | | | | | | | | | | | Fix IPv6 support in AF_RXRPC in the following ways: (1) When extracting the address from a received IPv4 packet, if the local transport socket is open for IPv6 then fill out the sockaddr_rxrpc struct for an IPv4-mapped-to-IPv6 AF_INET6 transport address instead of an AF_INET one. (2) When sending CHALLENGE or RESPONSE packets, the transport length needs to be set from the sockaddr_rxrpc::transport_len field rather than sizeof() on the IPv4 transport address. (3) When processing an IPv4 ICMP packet received by an IPv6 socket, set up the address correctly before searching for the affected peer. Signed-off-by: David Howells <dhowells@redhat.com>
* net: rxrpc: Replace time_t type with time64_t typeBaolin Wang2017-08-291-1/+1
| | | | | | | | | | | | | | | | Since the 'expiry' variable of 'struct key_preparsed_payload' has been changed to 'time64_t' type, which is year 2038 safe on 32bits system. In net/rxrpc subsystem, we need convert 'u32' type to 'time64_t' type when copying ticket expires time to 'prep->expiry', then this patch introduces two helper functions to help convert 'u32' to 'time64_t' type. This patch also uses ktime_get_real_seconds() to get current time instead of get_seconds() which is not year 2038 safe on 32bits system. Signed-off-by: Baolin Wang <baolin.wang@linaro.org> Signed-off-by: David Howells <dhowells@redhat.com>
* rxrpc: Move the packet.h include file into net/rxrpc/David Howells2017-07-211-1/+1
| | | | | | | | | | | Move the protocol description header file into net/rxrpc/ and rename it to protocol.h. It's no longer necessary to expose it as packets are no longer exposed to kernel services (such as AFS) that use the facility. The abort codes are transferred to the UAPI header instead as we pass these back to userspace and also to kernel services. Signed-off-by: David Howells <dhowells@redhat.com>
* rxrpc: Cache the congestion window settingDavid Howells2017-06-141-0/+2
| | | | | | | | | | | | | Cache the congestion window setting that was determined during a call's transmission phase when it finishes so that it can be used by the next call to the same peer, thereby shortcutting the slow-start algorithm. The value is stored in the rxrpc_peer struct and is accessed without locking. Each call takes the value that happens to be there when it starts and just overwrites the value when it finishes. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* rxrpc: Provide a cmsg to specify the amount of Tx data for a callDavid Howells2017-06-071-1/+2
| | | | | | | | | | | | | | | | | | | Provide a control message that can be specified on the first sendmsg() of a client call or the first sendmsg() of a service response to indicate the total length of the data to be transmitted for that call. Currently, because the length of the payload of an encrypted DATA packet is encrypted in front of the data, the packet cannot be encrypted until we know how much data it will hold. By specifying the length at the beginning of the transmit phase, each DATA packet length can be set before we start loading data from userspace (where several sendmsg() calls may contribute to a particular packet). An error will be returned if too little or too much data is presented in the Tx phase. Signed-off-by: David Howells <dhowells@redhat.com>
* rxrpc: Add service upgrade support for client connectionsDavid Howells2017-06-051-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Make it possible for a client to use AuriStor's service upgrade facility. The client does this by adding an RXRPC_UPGRADE_SERVICE control message to the first sendmsg() of a call. This takes no parameters. When recvmsg() starts returning data from the call, the service ID field in the returned msg_name will reflect the result of the upgrade attempt. If the upgrade was ignored, srx_service will match what was set in the sendmsg(); if the upgrade happened the srx_service will be altered to indicate the service the server upgraded to. Note that: (1) The choice of upgrade service is up to the server (2) Further client calls to the same server that would share a connection are blocked if an upgrade probe is in progress. (3) This should only be used to probe the service. Clients should then use the returned service ID in all subsequent communications with that server (and not set the upgrade). Note that the kernel will not retain this information should the connection expire from its cache. (4) If a server that supports upgrading is replaced by one that doesn't, whilst a connection is live, and if the replacement is running, say, OpenAFS 1.6.4 or older or an older IBM AFS, then the replacement server will not respond to packets sent to the upgraded connection. At this point, calls will time out and the server must be reprobed. Signed-off-by: David Howells <dhowells@redhat.com>
* rxrpc: Implement service upgradeDavid Howells2017-06-051-2/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Implement AuriStor's service upgrade facility. There are three problems that this is meant to deal with: (1) Various of the standard AFS RPC calls have IPv4 addresses in their requests and/or replies - but there's no room for including IPv6 addresses. (2) Definition of IPv6-specific RPC operations in the standard operation sets has not yet been achieved. (3) One could envision the creation a new service on the same port that as the original service. The new service could implement improved operations - and the client could try this first, falling back to the original service if it's not there. Unfortunately, certain servers ignore packets addressed to a service they don't implement and don't respond in any way - not even with an ABORT. This means that the client must then wait for the call timeout to occur. What service upgrade does is to see if the connection is marked as being 'upgradeable' and if so, change the service ID in the server and thus the request and reply formats. Note that the upgrade isn't mandatory - a server that supports only the original call set will ignore the upgrade request. In the protocol, the procedure is then as follows: (1) To request an upgrade, the first DATA packet in a new connection must have the userStatus set to 1 (this is normally 0). The userStatus value is normally ignored by the server. (2) If the server doesn't support upgrading, the reply packets will contain the same service ID as for the first request packet. (3) If the server does support upgrading, all future reply packets on that connection will contain the new service ID and the new service ID will be applied to *all* further calls on that connection as well. (4) The RPC op used to probe the upgrade must take the same request data as the shadow call in the upgrade set (but may return a different reply). GetCapability RPC ops were added to all standard sets for just this purpose. Ops where the request formats differ cannot be used for probing. (5) The client must wait for completion of the probe before sending any further RPC ops to the same destination. It should then use the service ID that recvmsg() reported back in all future calls. (6) The shadow service must have call definitions for all the operation IDs defined by the original service. To support service upgrading, a server should: (1) Call bind() twice on its AF_RXRPC socket before calling listen(). Each bind() should supply a different service ID, but the transport addresses must be the same. This allows the server to receive requests with either service ID. (2) Enable automatic upgrading by calling setsockopt(), specifying RXRPC_UPGRADEABLE_SERVICE and passing in a two-member array of unsigned shorts as the argument: unsigned short optval[2]; This specifies a pair of service IDs. They must be different and must match the service IDs bound to the socket. Member 0 is the service ID to upgrade from and member 1 is the service ID to upgrade to. Signed-off-by: David Howells <dhowells@redhat.com>
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-23 11:10:35 +0100