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2017-03-01Merge tag 'nfs-for-4.11-1' of git://git.linux-nfs.org/projects/anna/linux-nfsLinus Torvalds
Pull NFS client updates from Anna Schumaker: "Highlights include: Stable bugfixes: - NFSv4: Fix memory and state leak in _nfs4_open_and_get_state - xprtrdma: Fix Read chunk padding - xprtrdma: Per-connection pad optimization - xprtrdma: Disable pad optimization by default - xprtrdma: Reduce required number of send SGEs - nlm: Ensure callback code also checks that the files match - pNFS/flexfiles: If the layout is invalid, it must be updated before retrying - NFSv4: Fix reboot recovery in copy offload - Revert "NFSv4.1: Handle NFS4ERR_BADSESSION/NFS4ERR_DEADSESSION replies to OP_SEQUENCE" - NFSv4: fix getacl head length estimation - NFSv4: fix getacl ERANGE for sum ACL buffer sizes Features: - Add and use dprintk_cont macros - Various cleanups to NFS v4.x to reduce code duplication and complexity - Remove unused cr_magic related code - Improvements to sunrpc "read from buffer" code - Clean up sunrpc timeout code and allow changing TCP timeout parameters - Remove duplicate mw_list management code in xprtrdma - Add generic functions for encoding and decoding xdr streams Bugfixes: - Clean up nfs_show_mountd_netid - Make layoutreturn_ops static and use NULL instead of 0 to fix sparse warnings - Properly handle -ERESTARTSYS in nfs_rename() - Check if register_shrinker() failed during rpcauth_init() - Properly clean up procfs/pipefs entries - Various NFS over RDMA related fixes - Silence unititialized variable warning in sunrpc" * tag 'nfs-for-4.11-1' of git://git.linux-nfs.org/projects/anna/linux-nfs: (64 commits) NFSv4: fix getacl ERANGE for some ACL buffer sizes NFSv4: fix getacl head length estimation Revert "NFSv4.1: Handle NFS4ERR_BADSESSION/NFS4ERR_DEADSESSION replies to OP_SEQUENCE" NFSv4: Fix reboot recovery in copy offload pNFS/flexfiles: If the layout is invalid, it must be updated before retrying NFSv4: Clean up owner/group attribute decode SUNRPC: Add a helper function xdr_stream_decode_string_dup() NFSv4: Remove bogus "struct nfs_client" argument from decode_ace() NFSv4: Fix the underestimation of delegation XDR space reservation NFSv4: Replace callback string decode function with a generic NFSv4: Replace the open coded decode_opaque_inline() with the new generic NFSv4: Replace ad-hoc xdr encode/decode helpers with xdr_stream_* generics SUNRPC: Add generic helpers for xdr_stream encode/decode sunrpc: silence uninitialized variable warning nlm: Ensure callback code also checks that the files match sunrpc: Allow xprt->ops->timer method to sleep xprtrdma: Refactor management of mw_list field xprtrdma: Handle stale connection rejection xprtrdma: Properly recover FRWRs with in-flight FASTREG WRs xprtrdma: Shrink send SGEs array ...
2017-02-28Merge tag 'nfsd-4.11' of git://linux-nfs.org/~bfields/linuxLinus Torvalds
Pull nfsd updates from Bruce Fields: "The nfsd update this round is mainly a lot of miscellaneous cleanups and bugfixes. A couple changes could theoretically break working setups on upgrade. I don't expect complaints in practice, but they seem worth calling out just in case: - NFS security labels are now off by default; a new security_label export flag reenables it per export. But, having them on by default is a disaster, as it generally only makes sense if all your clients and servers have similar enough selinux policies. Thanks to Jason Tibbitts for pointing this out. - NFSv4/UDP support is off. It was never really supported, and the spec explicitly forbids it. We only ever left it on out of laziness; thanks to Jeff Layton for finally fixing that" * tag 'nfsd-4.11' of git://linux-nfs.org/~bfields/linux: (34 commits) nfsd: Fix display of the version string nfsd: fix configuration of supported minor versions sunrpc: don't register UDP port with rpcbind when version needs congestion control nfs/nfsd/sunrpc: enforce transport requirements for NFSv4 sunrpc: flag transports as having congestion control sunrpc: turn bitfield flags in svc_version into bools nfsd: remove superfluous KERN_INFO nfsd: special case truncates some more nfsd: minor nfsd_setattr cleanup NFSD: Reserve adequate space for LOCKT operation NFSD: Get response size before operation for all RPCs nfsd/callback: Drop a useless data copy when comparing sessionid nfsd/callback: skip the callback tag nfsd/callback: Cleanup callback cred on shutdown nfsd/idmap: return nfserr_inval for 0-length names SUNRPC/Cache: Always treat the invalid cache as unexpired SUNRPC: Drop all entries from cache_detail when cache_purge() svcrdma: Poll CQs in "workqueue" mode svcrdma: Combine list fields in struct svc_rdma_op_ctxt svcrdma: Remove unused sc_dto_q field ...
2017-02-24sunrpc: flag transports as having congestion controlJeff Layton
NFSv4 requires a transport protocol with congestion control in most cases. On an IP network, that means that NFSv4 over UDP should be forbidden. The situation with RDMA is a bit more nuanced, but most RDMA transports are suitable for this. For now, we assume that all RDMA transports are suitable, but we may need to revise that at some point. Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2017-02-22Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-nextLinus Torvalds
Pull networking updates from David Miller: "Highlights: 1) Support TX_RING in AF_PACKET TPACKET_V3 mode, from Sowmini Varadhan. 2) Simplify classifier state on sk_buff in order to shrink it a bit. From Willem de Bruijn. 3) Introduce SIPHASH and it's usage for secure sequence numbers and syncookies. From Jason A. Donenfeld. 4) Reduce CPU usage for ICMP replies we are going to limit or suppress, from Jesper Dangaard Brouer. 5) Introduce Shared Memory Communications socket layer, from Ursula Braun. 6) Add RACK loss detection and allow it to actually trigger fast recovery instead of just assisting after other algorithms have triggered it. From Yuchung Cheng. 7) Add xmit_more and BQL support to mvneta driver, from Simon Guinot. 8) skb_cow_data avoidance in esp4 and esp6, from Steffen Klassert. 9) Export MPLS packet stats via netlink, from Robert Shearman. 10) Significantly improve inet port bind conflict handling, especially when an application is restarted and changes it's setting of reuseport. From Josef Bacik. 11) Implement TX batching in vhost_net, from Jason Wang. 12) Extend the dummy device so that VF (virtual function) features, such as configuration, can be more easily tested. From Phil Sutter. 13) Avoid two atomic ops per page on x86 in bnx2x driver, from Eric Dumazet. 14) Add new bpf MAP, implementing a longest prefix match trie. From Daniel Mack. 15) Packet sample offloading support in mlxsw driver, from Yotam Gigi. 16) Add new aquantia driver, from David VomLehn. 17) Add bpf tracepoints, from Daniel Borkmann. 18) Add support for port mirroring to b53 and bcm_sf2 drivers, from Florian Fainelli. 19) Remove custom busy polling in many drivers, it is done in the core networking since 4.5 times. From Eric Dumazet. 20) Support XDP adjust_head in virtio_net, from John Fastabend. 21) Fix several major holes in neighbour entry confirmation, from Julian Anastasov. 22) Add XDP support to bnxt_en driver, from Michael Chan. 23) VXLAN offloads for enic driver, from Govindarajulu Varadarajan. 24) Add IPVTAP driver (IP-VLAN based tap driver) from Sainath Grandhi. 25) Support GRO in IPSEC protocols, from Steffen Klassert" * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1764 commits) Revert "ath10k: Search SMBIOS for OEM board file extension" net: socket: fix recvmmsg not returning error from sock_error bnxt_en: use eth_hw_addr_random() bpf: fix unlocking of jited image when module ronx not set arch: add ARCH_HAS_SET_MEMORY config net: napi_watchdog() can use napi_schedule_irqoff() tcp: Revert "tcp: tcp_probe: use spin_lock_bh()" net/hsr: use eth_hw_addr_random() net: mvpp2: enable building on 64-bit platforms net: mvpp2: switch to build_skb() in the RX path net: mvpp2: simplify MVPP2_PRS_RI_* definitions net: mvpp2: fix indentation of MVPP2_EXT_GLOBAL_CTRL_DEFAULT net: mvpp2: remove unused register definitions net: mvpp2: simplify mvpp2_bm_bufs_add() net: mvpp2: drop useless fields in mvpp2_bm_pool and related code net: mvpp2: remove unused 'tx_skb' field of 'struct mvpp2_tx_queue' net: mvpp2: release reference to txq_cpu[] entry after unmapping net: mvpp2: handle too large value in mvpp2_rx_time_coal_set() net: mvpp2: handle too large value handling in mvpp2_rx_pkts_coal_set() net: mvpp2: remove useless arguments in mvpp2_rx_{pkts, time}_coal_set ...
2017-02-20Merge branch 'locking-core-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull locking updates from Ingo Molnar: "The main changes in this cycle were: - Implement wraparound-safe refcount_t and kref_t types based on generic atomic primitives (Peter Zijlstra) - Improve and fix the ww_mutex code (Nicolai Hähnle) - Add self-tests to the ww_mutex code (Chris Wilson) - Optimize percpu-rwsems with the 'rcuwait' mechanism (Davidlohr Bueso) - Micro-optimize the current-task logic all around the core kernel (Davidlohr Bueso) - Tidy up after recent optimizations: remove stale code and APIs, clean up the code (Waiman Long) - ... plus misc fixes, updates and cleanups" * 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (50 commits) fork: Fix task_struct alignment locking/spinlock/debug: Remove spinlock lockup detection code lockdep: Fix incorrect condition to print bug msgs for MAX_LOCKDEP_CHAIN_HLOCKS lkdtm: Convert to refcount_t testing kref: Implement 'struct kref' using refcount_t refcount_t: Introduce a special purpose refcount type sched/wake_q: Clarify queue reinit comment sched/wait, rcuwait: Fix typo in comment locking/mutex: Fix lockdep_assert_held() fail locking/rtmutex: Flip unlikely() branch to likely() in __rt_mutex_slowlock() locking/rwsem: Reinit wake_q after use locking/rwsem: Remove unnecessary atomic_long_t casts jump_labels: Move header guard #endif down where it belongs locking/atomic, kref: Implement kref_put_lock() locking/ww_mutex: Turn off __must_check for now locking/atomic, kref: Avoid more abuse locking/atomic, kref: Use kref_get_unless_zero() more locking/atomic, kref: Kill kref_sub() locking/atomic, kref: Add kref_read() locking/atomic, kref: Add KREF_INIT() ...
2017-02-10xprtrdma: Refactor management of mw_list fieldChuck Lever
Clean up some duplicate code. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-02-10xprtrdma: Handle stale connection rejectionChuck Lever
A server rejects a connection attempt with STALE_CONNECTION when a client attempts to connect to a working remote service, but uses a QPN and GUID that corresponds to an old connection that was abandoned. This might occur after a client crashes and restarts. Fix rpcrdma_conn_upcall() to distinguish between a normal rejection and rejection of stale connection parameters. As an additional clean-up, remove the code that retries the connection attempt with different ORD/IRD values. Code audit of other ULP initiators shows no similar special case handling of initiator_depth or responder_resources. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-02-10xprtrdma: Properly recover FRWRs with in-flight FASTREG WRsChuck Lever
Sriharsha (sriharsha.basavapatna@broadcom.com) reports an occasional double DMA unmap of an FRWR MR when a connection is lost. I see one way this can happen. When a request requires more than one segment or chunk, rpcrdma_marshal_req loops, invoking ->frwr_op_map for each segment (MR) in each chunk. Each call posts a FASTREG Work Request to register one MR. Now suppose that the transport connection is lost part-way through marshaling this request. As part of recovering and resetting that req, rpcrdma_marshal_req invokes ->frwr_op_unmap_safe, which hands all the req's registered FRWRs to the MR recovery thread. But note: FRWR registration is asynchronous. So it's possible that some of these "already registered" FRWRs are fully registered, and some are still waiting for their FASTREG WR to complete. When the connection is lost, the "already registered" frmrs are marked FRMR_IS_VALID, and the "still waiting" WRs flush. Then frwr_wc_fastreg marks these frmrs FRMR_FLUSHED_FR. But thanks to ->frwr_op_unmap_safe, the MR recovery thread is doing an unreg / alloc_mr, a DMA unmap, and marking each of these frwrs FRMR_IS_INVALID, at the same time frwr_wc_fastreg might be running. - If the recovery thread runs last, then the frmr is marked FRMR_IS_INVALID, and life continues. - If frwr_wc_fastreg runs last, the frmr is marked FRMR_FLUSHED_FR, but the recovery thread has already DMA unmapped that MR. When ->frwr_op_map later re-uses this frmr, it sees it is not marked FRMR_IS_INVALID, and tries to recover it before using it, resulting in a second DMA unmap of the same MR. The fix is to guarantee in-flight FASTREG WRs have flushed before MR recovery runs on those FRWRs. Thus we depend on ro_unmap_safe (called from xprt_rdma_send_request on retransmit, or from xprt_rdma_free) to clean up old registrations as needed. Reported-by: Sriharsha Basavapatna <sriharsha.basavapatna@broadcom.com> Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Tested-by: Sriharsha Basavapatna <sriharsha.basavapatna@broadcom.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-02-10xprtrdma: Shrink send SGEs arrayChuck Lever
We no longer need to accommodate an xdr_buf whose pages start at an offset and cross extra page boundaries. If there are more partial or whole pages to send than there are available SGEs, the marshaling logic is now smart enough to use a Read chunk instead of failing. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-02-10xprtrdma: Reduce required number of send SGEsChuck Lever
The MAX_SEND_SGES check introduced in commit 655fec6987be ("xprtrdma: Use gathered Send for large inline messages") fails for devices that have a small max_sge. Instead of checking for a large fixed maximum number of SGEs, check for a minimum small number. RPC-over-RDMA will switch to using a Read chunk if an xdr_buf has more pages than can fit in the device's max_sge limit. This is considerably better than failing all together to mount the server. This fix supports devices that have as few as three send SGEs available. Reported-by: Selvin Xavier <selvin.xavier@broadcom.com> Reported-by: Devesh Sharma <devesh.sharma@broadcom.com> Reported-by: Honggang Li <honli@redhat.com> Reported-by: Ram Amrani <Ram.Amrani@cavium.com> Fixes: 655fec6987be ("xprtrdma: Use gathered Send for large ...") Cc: stable@vger.kernel.org # v4.9+ Tested-by: Honggang Li <honli@redhat.com> Tested-by: Ram Amrani <Ram.Amrani@cavium.com> Tested-by: Steve Wise <swise@opengridcomputing.com> Reviewed-by: Parav Pandit <parav@mellanox.com> Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-02-10xprtrdma: Disable pad optimization by defaultChuck Lever
Commit d5440e27d3e5 ("xprtrdma: Enable pad optimization") made the Linux client omit XDR round-up padding in normal Read and Write chunks so that the client doesn't have to register and invalidate 3-byte memory regions that contain no real data. Unfortunately, my cheery 2014 assessment that this optimization "is supported now by both Linux and Solaris servers" was premature. We've found bugs in Solaris in this area since commit d5440e27d3e5 ("xprtrdma: Enable pad optimization") was merged (SYMLINK is the main offender). So for maximum interoperability, I'm disabling this optimization again. If a CM private message is exchanged when connecting, the client recognizes that the server is Linux, and enables the optimization for that connection. Until now the Solaris server bugs did not impact common operations, and were thus largely benign. Soon, less capable devices on Linux NFS/RDMA clients will make use of Read chunks more often, and these Solaris bugs will prevent interoperation in more cases. Fixes: 677eb17e94ed ("xprtrdma: Fix XDR tail buffer marshalling") Cc: stable@vger.kernel.org # v4.9+ Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-02-10xprtrdma: Per-connection pad optimizationChuck Lever
Pad optimization is changed by echoing into /proc/sys/sunrpc/rdma_pad_optimize. This is a global setting, affecting all RPC-over-RDMA connections to all servers. The marshaling code picks up that value and uses it for decisions about how to construct each RPC-over-RDMA frame. Having it change suddenly in mid-operation can result in unexpected failures. And some servers a client mounts might need chunk round-up, while others don't. So instead, copy the pad_optimize setting into each connection's rpcrdma_ia when the transport is created, and use the copy, which can't change during the life of the connection, instead. This also removes a hack: rpcrdma_convert_iovs was using the remote-invalidation-expected flag to predict when it could leave out Write chunk padding. This is because the Linux server handles implicit XDR padding on Write chunks correctly, and only Linux servers can set the connection's remote-invalidation-expected flag. It's more sensible to use the pad optimization setting instead. Fixes: 677eb17e94ed ("xprtrdma: Fix XDR tail buffer marshalling") Cc: stable@vger.kernel.org # v4.9+ Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-02-10xprtrdma: Fix Read chunk paddingChuck Lever
When pad optimization is disabled, rpcrdma_convert_iovs still does not add explicit XDR round-up padding to a Read chunk. Commit 677eb17e94ed ("xprtrdma: Fix XDR tail buffer marshalling") incorrectly short-circuited the test for whether round-up padding is needed that appears later in rpcrdma_convert_iovs. However, if this is indeed a regular Read chunk (and not a Position-Zero Read chunk), the tail iovec _always_ contains the chunk's padding, and never anything else. So, it's easy to just skip the tail when padding optimization is enabled, and add the tail in a subsequent Read chunk segment, if disabled. Fixes: 677eb17e94ed ("xprtrdma: Fix XDR tail buffer marshalling") Cc: stable@vger.kernel.org # v4.9+ Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-02-10net: sunrpc: fix build errors when linux/phy*.h is removed from net/dsa.hRussell King
Removing linux/phy.h from net/dsa.h reveals a build error in the sunrpc code: net/sunrpc/xprtrdma/svc_rdma_backchannel.c: In function 'xprt_rdma_bc_put': net/sunrpc/xprtrdma/svc_rdma_backchannel.c:277:2: error: implicit declaration of function 'module_put' [-Werror=implicit-function-declaration] net/sunrpc/xprtrdma/svc_rdma_backchannel.c: In function 'xprt_setup_rdma_bc': net/sunrpc/xprtrdma/svc_rdma_backchannel.c:348:7: error: implicit declaration of function 'try_module_get' [-Werror=implicit-function-declaration] Fix this by adding linux/module.h to svc_rdma_backchannel.c Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk> Acked-by: Anna Schumaker <Anna.Schumaker@Netapp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-02-08svcrdma: Poll CQs in "workqueue" modeChuck Lever
svcrdma calls svc_xprt_put() in its completion handlers, which currently run in IRQ context. However, svc_xprt_put() is meant to be invoked in process context, not in IRQ context. After the last transport reference is gone, it directly calls a transport release function that expects to run in process context. Change the CQ polling modes to IB_POLL_WORKQUEUE so that svcrdma invokes svc_xprt_put() only in process context. As an added benefit, bottom half-disabled spin locking can be eliminated from I/O paths. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2017-02-08svcrdma: Combine list fields in struct svc_rdma_op_ctxtChuck Lever
Clean up: The free list and the dto_q list fields are never used at the same time. Reduce the size of struct svc_rdma_op_ctxt by combining these fields. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2017-02-08svcrdma: Remove unused sc_dto_q fieldChuck Lever
Clean up. Commit be99bb11400c ("svcrdma: Use new CQ API for RPC-over-RDMA server send CQs") removed code that used the sc_dto_q field, but neglected to remove sc_dto_q at the same time. Fixes: be99bb11400c ("svcrdma: Use new CQ API for RPC-over- ...") Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2017-02-08svcrdma: Clean up backchannel send header encodingChuck Lever
Replace C structure-based XDR decoding with pointer arithmetic. Pointer arithmetic is considered more portable. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2017-02-08svcrdma: Clean up RPC-over-RDMA Call header decoderChuck Lever
Replace C structure-based XDR decoding with pointer arithmetic. Pointer arithmetic is considered more portable. Rename the "decode" functions. Nothing is decoded here, they perform only transport header sanity checking. Use existing XDR naming conventions to help readability. Straight-line the hot path: - relocate the dprintk call sites out of line - remove unnecessary byte-swapping - reduce count of conditional branches Deprecate RDMA_MSGP. It's not properly spec'd by RFC5666, and therefore never used by any V1 client. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2017-02-08svcrdma: Clean up RPC-over-RDMA Reply header encoderChuck Lever
Replace C structure-based XDR decoding with pointer arithmetic. Pointer arithmetic is considered more portable, and is used throughout the kernel's existing XDR encoders. The gcc optimizer generates similar assembler code either way. Byte-swapping before a memory store on x86 typically results in an instruction pipeline stall. Avoid byte-swapping when encoding a new header. svcrdma currently doesn't alter a connection's credit grant value after the connection has been accepted, so it is effectively a constant. Cache the byte-swapped value in a separate field. Christoph suggested pulling the header encoding logic into the only function that uses it. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2017-02-08svcrdma: Another sendto chunk list parsing updateChuck Lever
Commit 5fdca6531434 ("svcrdma: Renovate sendto chunk list parsing") missed a spot. svc_rdma_xdr_get_reply_hdr_len() also assumes the Write list has only one Write chunk. There's no harm in making this code more general. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2017-01-14locking/atomic, kref: Add kref_read()Peter Zijlstra
Since we need to change the implementation, stop exposing internals. Provide kref_read() to read the current reference count; typically used for debug messages. Kills two anti-patterns: atomic_read(&kref->refcount) kref->refcount.counter Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-01-12svcrdma: avoid duplicate dma unmapping during error recoverySriharsha Basavapatna
In rdma_read_chunk_frmr() when ib_post_send() fails, the error code path invokes ib_dma_unmap_sg() to unmap the sg list. It then invokes svc_rdma_put_frmr() which in turn tries to unmap the same sg list through ib_dma_unmap_sg() again. This second unmap is invalid and could lead to problems when the iova being unmapped is subsequently reused. Remove the call to unmap in rdma_read_chunk_frmr() and let svc_rdma_put_frmr() handle it. Fixes: 412a15c0fe53 ("svcrdma: Port to new memory registration API") Cc: stable@vger.kernel.org Signed-off-by: Sriharsha Basavapatna <sriharsha.basavapatna@broadcom.com> Reviewed-by: Chuck Lever <chuck.lever@oracle.com> Reviewed-by: Yuval Shaia <yuval.shaia@oracle.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-12-16Merge tag 'nfsd-4.10' of git://linux-nfs.org/~bfields/linuxLinus Torvalds
Pull nfsd updates from Bruce Fields: "The one new feature is support for a new NFSv4.2 mode_umask attribute that makes ACL inheritance a little more useful in environments that default to restrictive umasks. Requires client-side support, also on its way for 4.10. Other than that, miscellaneous smaller fixes and cleanup, especially to the server rdma code" [ The client side of the umask attribute was merged yesterday ] * tag 'nfsd-4.10' of git://linux-nfs.org/~bfields/linux: nfsd: add support for the umask attribute sunrpc: use DEFINE_SPINLOCK() svcrdma: Further clean-up of svc_rdma_get_inv_rkey() svcrdma: Break up dprintk format in svc_rdma_accept() svcrdma: Remove unused variable in rdma_copy_tail() svcrdma: Remove unused variables in xprt_rdma_bc_allocate() svcrdma: Remove svc_rdma_op_ctxt::wc_status svcrdma: Remove DMA map accounting svcrdma: Remove BH-disabled spin locking in svc_rdma_send() svcrdma: Renovate sendto chunk list parsing svcauth_gss: Close connection when dropping an incoming message svcrdma: Clear xpt_bc_xps in xprt_setup_rdma_bc() error exit arm nfsd: constify reply_cache_stats_operations structure nfsd: update workqueue creation sunrpc: GFP_KERNEL should be GFP_NOFS in crypto code nfsd: catch errors in decode_fattr earlier nfsd: clean up supported attribute handling nfsd: fix error handling for clients that fail to return the layout nfsd: more robust allocation failure handling in nfsd_reply_cache_init
2016-11-30svcrdma: Further clean-up of svc_rdma_get_inv_rkey()Chuck Lever
No longer any need for the dprintk(). Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-11-30svcrdma: Break up dprintk format in svc_rdma_accept()Chuck Lever
The current code results in: Nov 7 14:50:19 klimt kernel: svcrdma: newxprt->sc_cm_id=ffff88085590c800, newxprt->sc_pd=ffff880852a7ce00#012 cm_id->device=ffff88084dd20000, sc_pd->device=ffff88084dd20000#012 cap.max_send_wr = 272#012 cap.max_recv_wr = 34#012 cap.max_send_sge = 32#012 cap.max_recv_sge = 32 Nov 7 14:50:19 klimt kernel: svcrdma: new connection ffff880855908000 accepted with the following attributes:#012 local_ip : 10.0.0.5#012 local_port#011 : 20049#012 remote_ip : 10.0.0.2#012 remote_port : 59909#012 max_sge : 32#012 max_sge_rd : 30#012 sq_depth : 272#012 max_requests : 32#012 ord : 16 Split up the output over multiple dprintks and take the opportunity to fix the display of IPv6 addresses. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-11-30svcrdma: Remove unused variable in rdma_copy_tail()Chuck Lever
Clean up. linux-2.6/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c: In function ‘rdma_copy_tail’: linux-2.6/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c:376:6: warning: variable ‘ret’ set but not used [-Wunused-but-set-variable] int ret; ^ Fixes: a97c331f9aa9 ("svcrdma: Handle additional inline content") Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-11-30svcrdma: Remove unused variables in xprt_rdma_bc_allocate()Chuck Lever
Clean up. /linux-2.6/net/sunrpc/xprtrdma/svc_rdma_backchannel.c: In function ‘xprt_rdma_bc_allocate’: linux-2.6/net/sunrpc/xprtrdma/svc_rdma_backchannel.c:169:23: warning: variable ‘rdma’ set but not used [-Wunused-but-set-variable] struct svcxprt_rdma *rdma; ^ Fixes: 5d252f90a800 ("svcrdma: Add class for RDMA backwards ...") Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-11-30svcrdma: Remove svc_rdma_op_ctxt::wc_statusChuck Lever
Clean up: Completion status is already reported in the individual completion handlers. Save a few bytes in struct svc_rdma_op_ctxt. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-11-30svcrdma: Remove DMA map accountingChuck Lever
Clean up: sc_dma_used is not required for correct operation. It is simply a debugging tool to report when svcrdma has leaked DMA maps. However, manipulating an atomic has a measurable CPU cost, and DMA map accounting specific to svcrdma will be meaningless once svcrdma is converted to use the new generic r/w API. A similar kind of debug accounting can be done simply by enabling the IOMMU or by using CONFIG_DMA_API_DEBUG, CONFIG_IOMMU_DEBUG, and CONFIG_IOMMU_LEAK. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-11-30svcrdma: Remove BH-disabled spin locking in svc_rdma_send()Chuck Lever
svcrdma's current SQ accounting algorithm takes sc_lock and disables bottom-halves while posting all RDMA Read, Write, and Send WRs. This is relatively heavyweight serialization. And note that Write and Send are already fully serialized by the xpt_mutex. Using a single atomic_t should be all that is necessary to guarantee that ib_post_send() is called only when there is enough space on the send queue. This is what the other RDMA-enabled storage targets do. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-11-30svcrdma: Renovate sendto chunk list parsingChuck Lever
The current sendto code appears to support clients that provide only one of a Read list, a Write list, or a Reply chunk. My reading of that code is that it doesn't support the following cases: - Read list + Write list - Read list + Reply chunk - Write list + Reply chunk - Read list + Write list + Reply chunk The protocol allows more than one Read or Write chunk in those lists. Some clients do send a Read list and Reply chunk simultaneously. NFSv4 WRITE uses a Read list for the data payload, and a Reply chunk because the GETATTR result in the reply can contain a large object like an ACL. Generalize one of the sendto code paths needed to support all of the above cases, and attempt to ensure that only one pass is done through the RPC Call's transport header to gather chunk list information for building the reply. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-11-30svcrdma: Clear xpt_bc_xps in xprt_setup_rdma_bc() error exit armChuck Lever
Logic copied from xs_setup_bc_tcp(). Fixes: 39a9beab5acb ('rpc: share one xps between all backchannels') Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-11-29xprtrdma: Relocate connection helper functionsChuck Lever
Clean up: Disentangle connection helpers from RPC-over-RDMA reply decoding functions. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2016-11-29xprtrdma: Update dprintk in rpcrdma_count_chunksChuck Lever
Clean up: offset and handle should be zero-filled, just like in the chunk encoders. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2016-11-29xprtrdma: Shorten QP access error messageChuck Lever
Clean up: The convention for this type of warning message is not to show the function name or "RPC: ". Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2016-11-29xprtrdma: Squelch "max send, max recv" messages at connect timeChuck Lever
Clean up: This message was intended to be a dprintk, as it is on the server-side. Fixes: 87cfb9a0c85c ('xprtrdma: Client-side support for ...') Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2016-11-29xprtrdma: Update documenting commentChuck Lever
Clean up: If reset fails, FRMRs are no longer abandoned, rather they are released immediately. Update the comment to reflect this. Fixes: 2ffc871a574d ('xprtrdma: Release orphaned MRs immediately') Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2016-11-29xprtrdma: Refactor FRMR invalidationChuck Lever
Clean up: After some recent updates, clarifications can be made to the FRMR invalidation logic. - Both the remote and local invalidation case mark the frmr INVALID, so make that a common path. - Manage the WR list more "tastefully" by replacing the conditional that discriminates between the list head and ->next pointers. - Use mw->mw_handle in all cases, since that has the same value as f->fr_mr->rkey, and is already in cache. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2016-11-29xprtrdma: Avoid calls to ro_unmap_safe()Chuck Lever
Micro-optimization: Most of the time, calls to ro_unmap_safe are expensive no-ops. Call only when there is work to do. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2016-11-29xprtrdma: Address coverity complaint about wait_for_completion()Chuck Lever
> ** CID 114101: Error handling issues (CHECKED_RETURN) > /net/sunrpc/xprtrdma/verbs.c: 355 in rpcrdma_create_id() Commit 5675add36e76 ("RPC/RDMA: harden connection logic against missing/late rdma_cm upcalls.") replaced wait_for_completion() calls with these two call sites. The original wait_for_completion() calls were added in the initial commit of verbs.c, which was commit c56c65fb67d6 ("RPCRDMA: rpc rdma verbs interface implementation"), but these returned void. rpcrdma_create_id() is called by the RDMA connect worker, which probably won't ever be interrupted. It is also called by rpcrdma_ia_open which is in the synchronous mount path, and ^C is possible there. Add a bit of logic at those two call sites to return if the waits return ERESTARTSYS. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2016-11-29xprtrdma: Support for SG_GAP devicesChuck Lever
Some devices (such as the Mellanox CX-4) can register, under a single R_key, a set of memory regions that are not contiguous. When this is done, all the segments in a Reply list, say, can then be invalidated in a single LocalInv Work Request (or via Remote Invalidation, which can invalidate exactly one R_key when completing a Receive). This means a single FastReg WR is used to register, and one or zero LocalInv WRs can invalidate, the memory involved with RDMA transfers on behalf of an RPC. In addition, xprtrdma constructs some Reply chunks from three or more segments. By registering them with SG_GAP, only one segment is needed for the Reply chunk, allowing the whole chunk to be invalidated remotely. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2016-11-29xprtrdma: Make FRWR send queue entry accounting more accurateChuck Lever
Verbs providers may perform house-keeping on the Send Queue during each signaled send completion. It is necessary therefore for a verbs consumer (like xprtrdma) to occasionally force a signaled send completion if it runs unsignaled most of the time. xprtrdma does not require signaled completions for Send or FastReg Work Requests, but does signal some LocalInv Work Requests. To ensure that Send Queue house-keeping can run before the Send Queue is more than half-consumed, xprtrdma forces a signaled completion on occasion by counting the number of Send Queue Entries it consumes. It currently does this by counting each ib_post_send as one Entry. Commit c9918ff56dfb ("xprtrdma: Add ro_unmap_sync method for FRWR") introduced the ability for frwr_op_unmap_sync to post more than one Work Request with a single post_send. Thus the underlying assumption of one Send Queue Entry per ib_post_send is no longer true. Also, FastReg Work Requests are currently never signaled. They should be signaled once in a while, just as Send is, to keep the accounting of consumed SQEs accurate. While we're here, convert the CQCOUNT macros to the currently preferred kernel coding style, which is inline functions. Fixes: c9918ff56dfb ("xprtrdma: Add ro_unmap_sync method for FRWR") Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2016-11-29xprtrdma: Cap size of callback buffer resourcesChuck Lever
When the inline threshold size is set to large values (say, 32KB) any NFSv4.1 CB request from the server gets a reply with status NFS4ERR_RESOURCE. Looks like there are some upper layer assumptions about the maximum size of a reply (for example, in process_op). Cap the size of the NFSv4 client's reply resources at a page. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2016-11-18Merge tag 'nfsd-4.9-2' of git://linux-nfs.org/~bfields/linuxLinus Torvalds
Pull nfsd bugfix from Bruce Fields: "Just one fix for an NFS/RDMA crash" * tag 'nfsd-4.9-2' of git://linux-nfs.org/~bfields/linux: sunrpc: svc_age_temp_xprts_now should not call setsockopt non-tcp transports
2016-11-14sunrpc: svc_age_temp_xprts_now should not call setsockopt non-tcp transportsScott Mayhew
This fixes the following panic that can occur with NFSoRDMA. general protection fault: 0000 [#1] SMP Modules linked in: rpcrdma ib_isert iscsi_target_mod ib_iser libiscsi scsi_transport_iscsi ib_srpt target_core_mod ib_srp scsi_transport_srp scsi_tgt ib_ipoib rdma_ucm ib_ucm ib_uverbs ib_umad rdma_cm ib_cm iw_cm mlx5_ib ib_core intel_powerclamp coretemp kvm_intel kvm sg ioatdma ipmi_devintf ipmi_ssif dcdbas iTCO_wdt iTCO_vendor_support pcspkr irqbypass sb_edac shpchp dca crc32_pclmul ghash_clmulni_intel edac_core lpc_ich aesni_intel lrw gf128mul glue_helper ablk_helper mei_me mei ipmi_si cryptd wmi ipmi_msghandler acpi_pad acpi_power_meter nfsd auth_rpcgss nfs_acl lockd grace sunrpc ip_tables xfs libcrc32c sd_mod crc_t10dif crct10dif_generic mgag200 i2c_algo_bit drm_kms_helper syscopyarea sysfillrect sysimgblt ahci fb_sys_fops ttm libahci mlx5_core tg3 crct10dif_pclmul drm crct10dif_common ptp i2c_core libata crc32c_intel pps_core fjes dm_mirror dm_region_hash dm_log dm_mod CPU: 1 PID: 120 Comm: kworker/1:1 Not tainted 3.10.0-514.el7.x86_64 #1 Hardware name: Dell Inc. PowerEdge R320/0KM5PX, BIOS 2.4.2 01/29/2015 Workqueue: events check_lifetime task: ffff88031f506dd0 ti: ffff88031f584000 task.ti: ffff88031f584000 RIP: 0010:[<ffffffff8168d847>] [<ffffffff8168d847>] _raw_spin_lock_bh+0x17/0x50 RSP: 0018:ffff88031f587ba8 EFLAGS: 00010206 RAX: 0000000000020000 RBX: 20041fac02080072 RCX: ffff88031f587fd8 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 20041fac02080072 RBP: ffff88031f587bb0 R08: 0000000000000008 R09: ffffffff8155be77 R10: ffff880322a59b00 R11: ffffea000bf39f00 R12: 20041fac02080072 R13: 000000000000000d R14: ffff8800c4fbd800 R15: 0000000000000001 FS: 0000000000000000(0000) GS:ffff880322a40000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f3c52d4547e CR3: 00000000019ba000 CR4: 00000000001407e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Stack: 20041fac02080002 ffff88031f587bd0 ffffffff81557830 20041fac02080002 ffff88031f587c78 ffff88031f587c40 ffffffff8155ae08 000000010157df32 0000000800000001 ffff88031f587c20 ffffffff81096acb ffffffff81aa37d0 Call Trace: [<ffffffff81557830>] lock_sock_nested+0x20/0x50 [<ffffffff8155ae08>] sock_setsockopt+0x78/0x940 [<ffffffff81096acb>] ? lock_timer_base.isra.33+0x2b/0x50 [<ffffffff8155397d>] kernel_setsockopt+0x4d/0x50 [<ffffffffa0386284>] svc_age_temp_xprts_now+0x174/0x1e0 [sunrpc] [<ffffffffa03b681d>] nfsd_inetaddr_event+0x9d/0xd0 [nfsd] [<ffffffff81691ebc>] notifier_call_chain+0x4c/0x70 [<ffffffff810b687d>] __blocking_notifier_call_chain+0x4d/0x70 [<ffffffff810b68b6>] blocking_notifier_call_chain+0x16/0x20 [<ffffffff815e8538>] __inet_del_ifa+0x168/0x2d0 [<ffffffff815e8cef>] check_lifetime+0x25f/0x270 [<ffffffff810a7f3b>] process_one_work+0x17b/0x470 [<ffffffff810a8d76>] worker_thread+0x126/0x410 [<ffffffff810a8c50>] ? rescuer_thread+0x460/0x460 [<ffffffff810b052f>] kthread+0xcf/0xe0 [<ffffffff810b0460>] ? kthread_create_on_node+0x140/0x140 [<ffffffff81696418>] ret_from_fork+0x58/0x90 [<ffffffff810b0460>] ? kthread_create_on_node+0x140/0x140 Code: ca 75 f1 5d c3 0f 1f 80 00 00 00 00 eb d9 66 0f 1f 44 00 00 0f 1f 44 00 00 55 48 89 e5 53 48 89 fb e8 7e 04 a0 ff b8 00 00 02 00 <f0> 0f c1 03 89 c2 c1 ea 10 66 39 c2 75 03 5b 5d c3 83 e2 fe 0f RIP [<ffffffff8168d847>] _raw_spin_lock_bh+0x17/0x50 RSP <ffff88031f587ba8> Signed-off-by: Scott Mayhew <smayhew@redhat.com> Fixes: c3d4879e ("sunrpc: Add a function to close temporary transports immediately") Reviewed-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-11-11Merge tag 'nfs-for-4.9-3' of git://git.linux-nfs.org/projects/anna/linux-nfsLinus Torvalds
Pull NFS client bugfixes from Anna Schumaker: "Most of these fix regressions in 4.9, and none are going to stable this time around. Bugfixes: - Trim extra slashes in v4 nfs_paths to fix tools that use this - Fix a -Wmaybe-uninitialized warnings - Fix suspicious RCU usages - Fix Oops when mounting multiple servers at once - Suppress a false-positive pNFS error - Fix a DMAR failure in NFS over RDMA" * tag 'nfs-for-4.9-3' of git://git.linux-nfs.org/projects/anna/linux-nfs: xprtrdma: Fix DMAR failure in frwr_op_map() after reconnect fs/nfs: Fix used uninitialized warn in nfs4_slot_seqid_in_use() NFS: Don't print a pNFS error if we aren't using pNFS NFS: Ignore connections that have cl_rpcclient uninitialized SUNRPC: Fix suspicious RCU usage NFSv4.1: work around -Wmaybe-uninitialized warning NFS: Trim extra slash in v4 nfs_path
2016-11-10xprtrdma: Fix DMAR failure in frwr_op_map() after reconnectChuck Lever
When a LOCALINV WR is flushed, the frmr is marked STALE, then frwr_op_unmap_sync DMA-unmaps the frmr's SGL. These STALE frmrs are then recovered when frwr_op_map hunts for an INVALID frmr to use. All other cases that need frmr recovery leave that SGL DMA-mapped. The FRMR recovery path unconditionally DMA-unmaps the frmr's SGL. To avoid DMA unmapping the SGL twice for flushed LOCAL_INV WRs, alter the recovery logic (rather than the hot frwr_op_unmap_sync path) to distinguish among these cases. This solution also takes care of the case where multiple LOCAL_INV WRs are issued for the same rpcrdma_req, some complete successfully, but some are flushed. Reported-by: Vasco Steinmetz <linux@kyberraum.net> Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Tested-by: Vasco Steinmetz <linux@kyberraum.net> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2016-11-01svcrdma: backchannel cannot share a page for send and rcv buffersChuck Lever
The underlying transport releases the page pointed to by rq_buffer during xprt_rdma_bc_send_request. When the backchannel reply arrives, rq_rbuffer then points to freed memory. Fixes: 68778945e46f ('SUNRPC: Separate buffer pointers for RPC ...') Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Cc: Jeff Layton <jlayton@redhat.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-10-28sunrpc: fix some missing rq_rbuffer assignmentsJeff Layton
We've been seeing some crashes in testing that look like this: BUG: unable to handle kernel NULL pointer dereference at (null) IP: [<ffffffff8135ce99>] memcpy_orig+0x29/0x110 PGD 212ca2067 PUD 212ca3067 PMD 0 Oops: 0002 [#1] SMP Modules linked in: rpcsec_gss_krb5 nfsv4 dns_resolver nfs fscache ppdev parport_pc i2c_piix4 sg parport i2c_core virtio_balloon pcspkr acpi_cpufreq nfsd auth_rpcgss nfs_acl lockd grace sunrpc ip_tables xfs libcrc32c sd_mod ata_generic pata_acpi virtio_scsi 8139too ata_piix libata 8139cp mii virtio_pci floppy virtio_ring serio_raw virtio CPU: 1 PID: 1540 Comm: nfsd Not tainted 4.9.0-rc1 #39 Hardware name: Red Hat KVM, BIOS 0.5.1 01/01/2007 task: ffff88020d7ed200 task.stack: ffff880211838000 RIP: 0010:[<ffffffff8135ce99>] [<ffffffff8135ce99>] memcpy_orig+0x29/0x110 RSP: 0018:ffff88021183bdd0 EFLAGS: 00010206 RAX: 0000000000000000 RBX: ffff88020d7fa000 RCX: 000000f400000000 RDX: 0000000000000014 RSI: ffff880212927020 RDI: 0000000000000000 RBP: ffff88021183be30 R08: 01000000ef896996 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffff880211704ca8 R13: ffff88021473f000 R14: 00000000ef896996 R15: ffff880211704800 FS: 0000000000000000(0000) GS:ffff88021fc80000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 0000000212ca1000 CR4: 00000000000006e0 Stack: ffffffffa01ea087 ffffffff63400001 ffff880215145e00 ffff880211bacd00 ffff88021473f2b8 0000000000000004 00000000d0679d67 ffff880211bacd00 ffff88020d7fa000 ffff88021473f000 0000000000000000 ffff88020d7faa30 Call Trace: [<ffffffffa01ea087>] ? svc_tcp_recvfrom+0x5a7/0x790 [sunrpc] [<ffffffffa01f84d8>] svc_recv+0xad8/0xbd0 [sunrpc] [<ffffffffa0262d5e>] nfsd+0xde/0x160 [nfsd] [<ffffffffa0262c80>] ? nfsd_destroy+0x60/0x60 [nfsd] [<ffffffff810a9418>] kthread+0xd8/0xf0 [<ffffffff816dbdbf>] ret_from_fork+0x1f/0x40 [<ffffffff810a9340>] ? kthread_park+0x60/0x60 Code: 00 00 48 89 f8 48 83 fa 20 72 7e 40 38 fe 7c 35 48 83 ea 20 48 83 ea 20 4c 8b 06 4c 8b 4e 08 4c 8b 56 10 4c 8b 5e 18 48 8d 76 20 <4c> 89 07 4c 89 4f 08 4c 89 57 10 4c 89 5f 18 48 8d 7f 20 73 d4 RIP [<ffffffff8135ce99>] memcpy_orig+0x29/0x110 RSP <ffff88021183bdd0> CR2: 0000000000000000 Both Bruce and Eryu ran a bisect here and found that the problematic patch was 68778945e46 (SUNRPC: Separate buffer pointers for RPC Call and Reply messages). That patch changed rpc_xdr_encode to use a new rq_rbuffer pointer to set up the receive buffer, but didn't change all of the necessary codepaths to set it properly. In particular the backchannel setup was missing. We need to set rq_rbuffer whenever rq_buffer is set. Ensure that it is. Reviewed-by: Chuck Lever <chuck.lever@oracle.com> Tested-by: Chuck Lever <chuck.lever@oracle.com> Reported-by: Eryu Guan <guaneryu@gmail.com> Tested-by: Eryu Guan <guaneryu@gmail.com> Fixes: 68778945e46 "SUNRPC: Separate buffer pointers..." Reported-by: J. Bruce Fields <bfields@fieldses.org> Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>