On Thu, Oct 27, 2022 at 05:30 PM +02, Jakub Sitnicki wrote: > On Thu, Oct 27, 2022 at 12:36 PM +02, Jakub Sitnicki wrote: > > [...] > >> While testing Cong's fix for the dead lock in sk_psock_backlog [1], I've >> noticed that this change introduces a memory accounting issue. See >> warnings below. >> >> So what I've proposed is not completely sound. We will need to revisit >> it. >> >> [1] https://lore.kernel.org/bpf/Y0xJUc%2FLRu8K%2FAf8@pop-os.localdomain/ >> >> --8<-- >> bash-5.1# uname -r >> 6.0.0-rc3-00892-g3f8ef65af927 >> bash-5.1# ./test_sockmap >> # 1/ 6 sockmap::txmsg test passthrough:OK >> # 2/ 6 sockmap::txmsg test redirect:OK >> # 3/ 1 sockmap::txmsg test redirect wait send mem:OK >> # 4/ 6 sockmap::txmsg test drop:OK >> # 5/ 6 sockmap::txmsg test ingress redirect:OK >> # 6/ 7 sockmap::txmsg test skb:OK >> # 7/ 8 sockmap::txmsg test apply:OK >> # 8/12 sockmap::txmsg test cork:OK >> [ 46.324023] ------------[ cut here ]------------ >> [ 46.325114] WARNING: CPU: 3 PID: 199 at net/core/stream.c:206 >> sk_stream_kill_queues+0xd6/0xf0 >> [ 46.326573] Modules linked in: >> [ 46.327105] CPU: 3 PID: 199 Comm: test_sockmap Not tainted >> 6.0.0-rc3-00892-g3f8ef65af927 #36 >> [ 46.328406] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS >> 1.15.0-1.fc35 04/01/2014 >> [ 46.330000] RIP: 0010:sk_stream_kill_queues+0xd6/0xf0 >> [ 46.330816] Code: 29 5b 5d 31 c0 89 c2 89 c6 89 c7 c3 48 89 df e8 10 14 ff ff >> 8b 83 70 02 00 00 8b b3 28 02 00 00 85 c0 74 d9 0f 0b 85 f6 74 d7 <0f> 0b 5b 5d >> 31 c0 89 c2 89 c6 89 c7 c3 0f 0b eb 92 66 0f 1f 84 00 >> [ 46.331889] RSP: 0018:ffffc90000bc7d48 EFLAGS: 00010206 >> [ 46.332186] RAX: 0000000000000000 RBX: ffff88810567dc00 RCX: 0000000000000000 >> [ 46.332583] RDX: 0000000000000000 RSI: 0000000000000fc0 RDI: ffff88810567ddb8 >> [ 46.332991] RBP: ffff88810567ddb8 R08: 0000000000000000 R09: 0000000000000000 >> [ 46.333321] R10: 0000000000000000 R11: 0000000000000000 R12: ffff88810567dc00 >> [ 46.333661] R13: ffff888103894500 R14: ffff888101fdf8e0 R15: ffff88810567dd30 >> [ 46.334074] FS: 00007f420a4d8b80(0000) GS:ffff88813bd80000(0000) knlGS:0000000000000000 >> [ 46.334532] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 >> [ 46.334881] CR2: 00007f420a4d8af8 CR3: 0000000102e17001 CR4: 0000000000370ee0 >> [ 46.335300] Call Trace: >> [ 46.335444] <TASK> >> [ 46.335573] inet_csk_destroy_sock+0x4f/0x110 >> [ 46.335832] tcp_rcv_state_process+0xdcf/0x1140 >> [ 46.336076] ? tcp_v4_do_rcv+0x77/0x2a0 >> [ 46.336299] tcp_v4_do_rcv+0x77/0x2a0 >> [ 46.336512] __release_sock+0x58/0xb0 >> [ 46.336721] __tcp_close+0x186/0x450 >> [ 46.336883] tcp_close+0x20/0x70 >> [ 46.337026] inet_release+0x39/0x80 >> [ 46.337177] __sock_release+0x37/0xa0 >> [ 46.337341] sock_close+0x14/0x20 >> [ 46.337486] __fput+0xa2/0x260 >> [ 46.337622] task_work_run+0x59/0xa0 >> [ 46.337785] exit_to_user_mode_prepare+0x185/0x190 >> [ 46.337992] syscall_exit_to_user_mode+0x19/0x40 >> [ 46.338189] do_syscall_64+0x42/0x90 >> [ 46.338350] entry_SYSCALL_64_after_hwframe+0x46/0xb0 >> [ 46.338565] RIP: 0033:0x7f420a618eb7 >> [ 46.338741] Code: ff e8 7d e2 01 00 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 f3 >> 0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 b8 03 00 00 00 0f 05 <48> 3d 00 f0 >> ff ff 77 41 c3 48 83 ec 18 89 7c 24 0c e8 43 cd f5 ff >> [ 46.339596] RSP: 002b:00007ffd54748df8 EFLAGS: 00000246 ORIG_RAX: 0000000000000003 >> [ 46.339944] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00007f420a618eb7 >> [ 46.340349] RDX: 0000000000000018 RSI: 00007ffd54748d50 RDI: 0000000000000019 >> [ 46.340753] RBP: 00007ffd54748e40 R08: 00007ffd54748d50 R09: 00007ffd54748d50 >> [ 46.341162] R10: 00007ffd54748d50 R11: 0000000000000246 R12: 00007ffd54749118 >> [ 46.341574] R13: 000000000040d0ad R14: 0000000000474df8 R15: 00007f420a769000 >> [ 46.341927] </TASK> >> [ 46.342025] irq event stamp: 206385 >> [ 46.342175] hardirqs last enabled at (206393): [<ffffffff810f1f82>] >> __up_console_sem+0x52/0x60 >> [ 46.342546] hardirqs last disabled at (206400): [<ffffffff810f1f67>] >> __up_console_sem+0x37/0x60 >> [ 46.342965] softirqs last enabled at (206414): [<ffffffff8107bcc5>] >> __irq_exit_rcu+0xc5/0x120 >> [ 46.343454] softirqs last disabled at (206409): [<ffffffff8107bcc5>] >> __irq_exit_rcu+0xc5/0x120 >> [ 46.343951] ---[ end trace 0000000000000000 ]--- >> [ 46.344199] ------------[ cut here ]------------ >> [ 46.344421] WARNING: CPU: 3 PID: 199 at net/ipv4/af_inet.c:154 >> inet_sock_destruct+0x1a0/0x1d0 >> [ 46.344897] Modules linked in: >> [ 46.345074] CPU: 3 PID: 199 Comm: test_sockmap Tainted: G W >> 6.0.0-rc3-00892-g3f8ef65af927 #36 >> [ 46.345549] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS >> 1.15.0-1.fc35 04/01/2014 >> [ 46.346028] RIP: 0010:inet_sock_destruct+0x1a0/0x1d0 >> [ 46.346313] Code: ff 49 8b bc 24 60 02 00 00 e8 cc 1e e9 ff 49 8b bc 24 88 00 >> 00 00 5b 41 5c e9 bc 1e e9 ff 41 8b 84 24 28 02 00 00 85 c0 74 ca <0f> 0b eb c6 >> 4c 89 e7 e8 a4 2d e6 ff e9 50 ff ff ff 0f 0b 41 8b 84 >> [ 46.347370] RSP: 0018:ffffc90000bc7e40 EFLAGS: 00010206 >> [ 46.347670] RAX: 0000000000000fc0 RBX: ffff88810567dd60 RCX: 0000000000000000 >> [ 46.348090] RDX: 0000000000000303 RSI: 0000000000000fc0 RDI: ffff88810567dd60 >> [ 46.348495] RBP: ffff88810567dc00 R08: 0000000000000000 R09: 0000000000000000 >> [ 46.348921] R10: 0000000000000000 R11: 0000000000000000 R12: ffff88810567dc00 >> [ 46.349306] R13: ffff8881001d48e0 R14: ffff88810257a3a8 R15: 0000000000000000 >> [ 46.349717] FS: 00007f420a4d8b80(0000) GS:ffff88813bd80000(0000) knlGS:0000000000000000 >> [ 46.350191] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 >> [ 46.350531] CR2: 00007f420a4d8af8 CR3: 0000000102e17001 CR4: 0000000000370ee0 >> [ 46.350947] Call Trace: >> [ 46.351098] <TASK> >> [ 46.351246] __sk_destruct+0x23/0x250 >> [ 46.351599] inet_release+0x39/0x80 >> [ 46.351835] __sock_release+0x37/0xa0 >> [ 46.352059] sock_close+0x14/0x20 >> [ 46.352206] __fput+0xa2/0x260 >> [ 46.352347] task_work_run+0x59/0xa0 >> [ 46.352515] exit_to_user_mode_prepare+0x185/0x190 >> [ 46.352728] syscall_exit_to_user_mode+0x19/0x40 >> [ 46.352954] do_syscall_64+0x42/0x90 >> [ 46.353119] entry_SYSCALL_64_after_hwframe+0x46/0xb0 >> [ 46.353342] RIP: 0033:0x7f420a618eb7 >> [ 46.353498] Code: ff e8 7d e2 01 00 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 f3 >> 0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 b8 03 00 00 00 0f 05 <48> 3d 00 f0 >> ff ff 77 41 c3 48 83 ec 18 89 7c 24 0c e8 43 cd f5 ff >> [ 46.354284] RSP: 002b:00007ffd54748df8 EFLAGS: 00000246 ORIG_RAX: 0000000000000003 >> [ 46.354601] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00007f420a618eb7 >> [ 46.354908] RDX: 0000000000000018 RSI: 00007ffd54748d50 RDI: 0000000000000019 >> [ 46.355308] RBP: 00007ffd54748e40 R08: 00007ffd54748d50 R09: 00007ffd54748d50 >> [ 46.355710] R10: 00007ffd54748d50 R11: 0000000000000246 R12: 00007ffd54749118 >> [ 46.356117] R13: 000000000040d0ad R14: 0000000000474df8 R15: 00007f420a769000 >> [ 46.356532] </TASK> >> [ 46.356664] irq event stamp: 206837 >> [ 46.356873] hardirqs last enabled at (206847): [<ffffffff810f1f82>] >> __up_console_sem+0x52/0x60 >> [ 46.357369] hardirqs last disabled at (206854): [<ffffffff810f1f67>] >> __up_console_sem+0x37/0x60 >> [ 46.357864] softirqs last enabled at (206604): [<ffffffff8107bcc5>] >> __irq_exit_rcu+0xc5/0x120 >> [ 46.358358] softirqs last disabled at (206591): [<ffffffff8107bcc5>] >> __irq_exit_rcu+0xc5/0x120 >> [ 46.358865] ---[ end trace 0000000000000000 ]--- >> # 9/ 3 sockmap::txmsg test hanging corks:OK > > [...] > > Actually, we had a fix for these warnings in 9c34e38c4a87 ("bpf, > sockmap: Fix memleak in tcp_bpf_sendmsg while sk msg is full") [1]. > > But they reappear for me in v5.18-rc1. Trying to bisect what went > wrong... > > [1] https://lore.kernel.org/bpf/20220304081145.2037182-3-wangyufen@xxxxxxxxxx Traced it down to 84472b436e76 ("bpf, sockmap: Fix more uncharged while msg has more_data"), which was the next commit after the one I thought contained the fix, that is 9c34e38c4a87. I started a discussion in the thread for the patch set [1], as the warnings look completely unrelated to this change. [1] https://lore.kernel.org/netdev/87v8o5gdw2.fsf@xxxxxxxxxxxxxx/
