Re: [PATCH net-next v10 08/16] tls: Inline do_tcp_sendpages()

[Tariq Toukan]

On 19/06/2023 12:35, David Howells wrote:
> Tariq Toukan <ttoukan.linux@xxxxxxxxx> wrote:
>
> > Any other debug information that we can provide to progress with the analysis?
>
> Can you see if the problem still happens on this branch of my tree?
>
> https://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs.git/log/?h=sendpage-3-frag
>
> It eases the restriction that the WARN_ON is warning about by (in patch 1[*])
> copying slab objects into page fragments.
>
> David
>
> [*] "net: Copy slab data for sendmsg(MSG_SPLICE_PAGES)"

Hi David,

Unfortunately, it still happens:

------------[ cut here ]------------
WARNING: CPU: 2 PID: 93427 at net/core/skbuff.c:7013 
skb_splice_from_iter+0x299/0x550
Modules linked in: bonding nf_tables vfio_pci ip_gre geneve ib_umad 
rdma_ucm ipip tunnel4 ip6_gre gre ip6_tunnel tunnel6 ib_ipoib 
mlx5_vfio_pci vfio_pci_core mlx5_ib ib_uverbs mlx5_core sch_mqprio 
sch_mqprio_lib sch_netem iptable_raw vfio_iommu_type1 vfio openvswitch 
nsh rpcrdma ib_iser libiscsi scsi_transport_iscsi rdma_cm iw_cm ib_cm 
ib_core xt_conntrack xt_MASQUERADE nf_conntrack_netlink nfnetlink 
xt_addrtype iptable_nat nf_nat br_netfilter rpcsec_gss_krb5 auth_rpcgss 
oid_registry overlay zram zsmalloc fuse [last unloaded: nf_tables]
CPU: 2 PID: 93427 Comm: nginx_openssl_3 Tainted: G        W 
6.4.0-rc6_net_next_mlx5_9b6e6b6 #1
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 
rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014
RIP: 0010:skb_splice_from_iter+0x299/0x550
Code: 49 8b 57 08 f6 c2 01 0f 85 89 01 00 00 8b 0d 22 b3 4a 01 4c 89 fa 
85 c9 0f 8f 81 01 00 00 48 8b 12 80 e6 02 0f 84 a3 00 00 00 <0f> 0b 48 
c7 c1 fb ff ff ff 44 01 6b 70 44 01 6b 74 44 01 ab d0 00
RSP: 0018:ffff8882a16d3a80 EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffff88821a89ee00 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffea0004c2cfc0 RDI: ffff88821a89ee00
RBP: 0000000000000f34 R08: 0000000000000011 R09: 0000000000000f34
R10: 0000000000000000 R11: 000000000000000d R12: 0000000000000004
R13: 0000000000002d0f R14: 0000000000000f34 R15: ffffea0004c2d000
FS:  00007f5c383eb740(0000) GS:ffff88885f880000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000002ea5000 CR3: 0000000264ffe006 CR4: 0000000000370ea0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 ? __warn+0x79/0x120
 ? skb_splice_from_iter+0x299/0x550
 ? report_bug+0x17c/0x190
 ? handle_bug+0x3c/0x60
 ? exc_invalid_op+0x14/0x70
 ? asm_exc_invalid_op+0x16/0x20
 ? skb_splice_from_iter+0x299/0x550
 tcp_sendmsg_locked+0x375/0xd00
 tls_push_sg+0xdd/0x230
 tls_push_data+0x6de/0xb00
 tls_device_sendmsg+0x7a/0xd0
 sock_sendmsg+0x38/0x60
 sock_write_iter+0x97/0x100
 vfs_write+0x2df/0x380
 ksys_write+0xa7/0xe0
 do_syscall_64+0x3d/0x90
 entry_SYSCALL_64_after_hwframe+0x46/0xb0
RIP: 0033:0x7f5c381018b7
Code: 0f 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b7 0f 1f 00 f3 0f 1e 
fa 64 8b 04 25 18 00 00 00 85 c0 75 10 b8 01 00 00 00 0f 05 <48> 3d 00 
f0 ff ff 77 51 c3 48 83 ec 28 48 89 54 24 18 48 89 74 24
RSP: 002b:00007ffee9750848 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000004000 RCX: 00007f5c381018b7
RDX: 0000000000004000 RSI: 0000000002ea2dc0 RDI: 00000000000000d1
RBP: 0000000001d1bbe0 R08: 00007ffee974ffe0 R09: 0000000000000001
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000002ea2dc0
R13: 0000000001d2a7e0 R14: 0000000000004000 R15: 0000000000004000
 </TASK>
---[ end trace 0000000000000000 ]---