kernel/git/stable/linux.git/net/smc, branch linux-4.19.y

net/smc: set rmb's SG_MAX_SINGLE_ALLOC limitation only when CONFIG_ARCH_NO_SG_CHAIN is defined

2024-08-19T03:31:57+00:00

[ Upstream commit 3ac14b9dfbd345e891d48d89f6c2fa519848f0f4 ] SG_MAX_SINGLE_ALLOC is used to limit maximum number of entries that will be allocated in one piece of scatterlist. When the entries of scatterlist exceeds SG_MAX_SINGLE_ALLOC, sg chain will be used. From commit 7c703e54cc71 ("arch: switch the default on ARCH_HAS_SG_CHAIN"), we can know that the macro CONFIG_ARCH_NO_SG_CHAIN is used to identify whether sg chain is supported. So, SMC-R's rmb buffer should be limited by SG_MAX_SINGLE_ALLOC only when the macro CONFIG_ARCH_NO_SG_CHAIN is defined. Fixes: a3fe3d01bd0d ("net/smc: introduce sg-logic for RMBs") Signed-off-by: Guangguan Wang Co-developed-by: Wen Gu Signed-off-by: Wen Gu Signed-off-by: David S. Miller Signed-off-by: Sasha Levin

net/smc: Allow SMC-D 1MB DMB allocations

2024-08-19T03:31:57+00:00

[ Upstream commit 67161779a9ea926fccee8de047ae66cbd3482b91 ] Commit a3fe3d01bd0d7 ("net/smc: introduce sg-logic for RMBs") introduced a restriction for RMB allocations as used by SMC-R. However, SMC-D does not use scatter-gather lists to back its DMBs, yet it was limited by this restriction, still. This patch exempts SMC, but limits allocations to the maximum RMB/DMB size respectively. Signed-off-by: Stefan Raspl Signed-off-by: Guvenc Gulce Signed-off-by: David S. Miller Stable-dep-of: 3ac14b9dfbd3 ("net/smc: set rmb's SG_MAX_SINGLE_ALLOC limitation only when CONFIG_ARCH_NO_SG_CHAIN is defined") Signed-off-by: Sasha Levin

net/smc: fix illegal rmb_desc access in SMC-D connection dump

2024-02-23T07:12:41+00:00

[ Upstream commit dbc153fd3c142909e564bb256da087e13fbf239c ] A crash was found when dumping SMC-D connections. It can be reproduced by following steps: - run nginx/wrk test: smc_run nginx smc_run wrk -t 16 -c 1000 -d -H 'Connection: Close' - continuously dump SMC-D connections in parallel: watch -n 1 'smcss -D' BUG: kernel NULL pointer dereference, address: 0000000000000030 CPU: 2 PID: 7204 Comm: smcss Kdump: loaded Tainted: G E 6.7.0+ #55 RIP: 0010:__smc_diag_dump.constprop.0+0x5e5/0x620 [smc_diag] Call Trace: ? __die+0x24/0x70 ? page_fault_oops+0x66/0x150 ? exc_page_fault+0x69/0x140 ? asm_exc_page_fault+0x26/0x30 ? __smc_diag_dump.constprop.0+0x5e5/0x620 [smc_diag] ? __kmalloc_node_track_caller+0x35d/0x430 ? __alloc_skb+0x77/0x170 smc_diag_dump_proto+0xd0/0xf0 [smc_diag] smc_diag_dump+0x26/0x60 [smc_diag] netlink_dump+0x19f/0x320 __netlink_dump_start+0x1dc/0x300 smc_diag_handler_dump+0x6a/0x80 [smc_diag] ? __pfx_smc_diag_dump+0x10/0x10 [smc_diag] sock_diag_rcv_msg+0x121/0x140 ? __pfx_sock_diag_rcv_msg+0x10/0x10 netlink_rcv_skb+0x5a/0x110 sock_diag_rcv+0x28/0x40 netlink_unicast+0x22a/0x330 netlink_sendmsg+0x1f8/0x420 __sock_sendmsg+0xb0/0xc0 ____sys_sendmsg+0x24e/0x300 ? copy_msghdr_from_user+0x62/0x80 ___sys_sendmsg+0x7c/0xd0 ? __do_fault+0x34/0x160 ? do_read_fault+0x5f/0x100 ? do_fault+0xb0/0x110 ? __handle_mm_fault+0x2b0/0x6c0 __sys_sendmsg+0x4d/0x80 do_syscall_64+0x69/0x180 entry_SYSCALL_64_after_hwframe+0x6e/0x76 It is possible that the connection is in process of being established when we dump it. Assumed that the connection has been registered in a link group by smc_conn_create() but the rmb_desc has not yet been initialized by smc_buf_create(), thus causing the illegal access to conn->rmb_desc. So fix it by checking before dump. Fixes: 4b1b7d3b30a6 ("net/smc: add SMC-D diag support") Signed-off-by: Wen Gu Reviewed-by: Dust Li Reviewed-by: Wenjia Zhang Signed-off-by: David S. Miller Signed-off-by: Sasha Levin

net/smc: fix dangling sock under state SMC_APPFINCLOSEWAIT

2023-11-20T09:29:21+00:00

[ Upstream commit 5211c9729484c923f8d2e06bd29f9322cc42bb8f ] Considering scenario: smc_cdc_rx_handler __smc_release sock_set_flag smc_close_active() sock_set_flag __set_bit(DEAD) __set_bit(DONE) Dues to __set_bit is not atomic, the DEAD or DONE might be lost. if the DEAD flag lost, the state SMC_CLOSED will be never be reached in smc_close_passive_work: if (sock_flag(sk, SOCK_DEAD) && smc_close_sent_any_close(conn)) { sk->sk_state = SMC_CLOSED; } else { /* just shutdown, but not yet closed locally */ sk->sk_state = SMC_APPFINCLOSEWAIT; } Replace sock_set_flags or __set_bit to set_bit will fix this problem. Since set_bit is atomic. Fixes: b38d732477e4 ("smc: socket closing and linkgroup cleanup") Signed-off-by: D. Wythe Reviewed-by: Dust Li Signed-off-by: David S. Miller Signed-off-by: Sasha Levin

net/smc: wait for pending work before clcsock release_sock

2023-11-20T09:29:21+00:00

[ Upstream commit fd57770dd198f5b2ddd5b9e6bf282cf98d63adb9 ] When the clcsock is already released using sock_release() and a pending smc_listen_work accesses the clcsock than that will fail. Solve this by canceling and waiting for the work to complete first. Because the work holds the sock_lock it must make sure that the lock is not hold before the new helper smc_clcsock_release() is invoked. And before the smc_listen_work starts working check if the parent listen socket is still valid, otherwise stop the work early. Signed-off-by: Karsten Graul Signed-off-by: Ursula Braun Signed-off-by: David S. Miller Stable-dep-of: 5211c9729484 ("net/smc: fix dangling sock under state SMC_APPFINCLOSEWAIT") Signed-off-by: Sasha Levin

net/smc: postpone release of clcsock

2023-11-20T09:29:21+00:00

[ Upstream commit b03faa1fafc8018295401dc558bdc76362d860a4 ] According to RFC7609 (http://www.rfc-editor.org/info/rfc7609) first the SMC-R connection is shut down and then the normal TCP connection FIN processing drives cleanup of the internal TCP connection. The unconditional release of the clcsock during active socket closing has to be postponed if the peer has not yet signalled socket closing. Signed-off-by: Ursula Braun Signed-off-by: David S. Miller Stable-dep-of: 5211c9729484 ("net/smc: fix dangling sock under state SMC_APPFINCLOSEWAIT") Signed-off-by: Sasha Levin

net/smc: Remove redundant refcount increase

2022-09-15T10:17:03+00:00

[ Upstream commit a8424a9b4522a3ab9f32175ad6d848739079071f ] For passive connections, the refcount increment has been done in smc_clcsock_accept()-->smc_sock_alloc(). Fixes: 3b2dec2603d5 ("net/smc: restructure client and server code in af_smc") Signed-off-by: Yacan Liu Reviewed-by: Tony Lu Link: https://lore.kernel.org/r/20220830152314.838736-1-liuyacan@corp.netease.com Signed-off-by: Paolo Abeni Signed-off-by: Sasha Levin

net/smc: non blocking recvmsg() return -EAGAIN when no data and signal_pending

2022-05-18T07:42:48+00:00

[ Upstream commit f3c46e41b32b6266cf60b0985c61748f53bf1c61 ] Non blocking sendmsg will return -EAGAIN when any signal pending and no send space left, while non blocking recvmsg return -EINTR when signal pending and no data received. This may makes confused. As TCP returns -EAGAIN in the conditions described above. Align the behavior of smc with TCP. Fixes: 846e344eb722 ("net/smc: add receive timeout check") Signed-off-by: Guangguan Wang Reviewed-by: Tony Lu Acked-by: Karsten Graul Link: https://lore.kernel.org/r/20220512030820.73848-1-guangguan.wang@linux.alibaba.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin

net/smc: correct settings of RMB window update limit

2022-04-15T12:15:02+00:00

[ Upstream commit 6bf536eb5c8ca011d1ff57b5c5f7c57ceac06a37 ] rmbe_update_limit is used to limit announcing receive window updating too frequently. RFC7609 request a minimal increase in the window size of 10% of the receive buffer space. But current implementation used: min_t(int, rmbe_size / 10, SOCK_MIN_SNDBUF / 2) and SOCK_MIN_SNDBUF / 2 == 2304 Bytes, which is almost always less then 10% of the receive buffer space. This causes the receiver always sending CDC message to update its consumer cursor when it consumes more then 2K of data. And as a result, we may encounter something like "TCP silly window syndrome" when sending 2.5~8K message. This patch fixes this using max(rmbe_size / 10, SOCK_MIN_SNDBUF / 2). With this patch and SMC autocorking enabled, qperf 2K/4K/8K tcp_bw test shows 45%/75%/40% increase in throughput respectively. Signed-off-by: Dust Li Signed-off-by: David S. Miller Signed-off-by: Sasha Levin

net/smc: fix unexpected SMC_CLC_DECL_ERR_REGRMB error cause by server

2022-03-08T18:04:08+00:00

commit 4940a1fdf31c39f0806ac831cde333134862030b upstream. The problem of SMC_CLC_DECL_ERR_REGRMB on the server is very clear. Based on the fact that whether a new SMC connection can be accepted or not depends on not only the limit of conn nums, but also the available entries of rtoken. Since the rtoken release is trigger by peer, while the conn nums is decrease by local, tons of thing can happen in this time difference. This only thing that needs to be mentioned is that now all connection creations are completely protected by smc_server_lgr_pending lock, it's enough to check only the available entries in rtokens_used_mask. Fixes: cd6851f30386 ("smc: remote memory buffers (RMBs)") Signed-off-by: D. Wythe Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman