46bdf370f6
This happens if assign_name() returns failure when called from ib_register_device(), that will lead to the following panic in every time that someone touches the port_data's data members. BUG: unable to handle kernel NULL pointer dereference at 00000000000000c0 PGD 0 P4D 0 Oops: 0002 [#1] SMP PTI CPU: 19 PID: 1994 Comm: systemd-udevd Not tainted 5.1.0-rc5+ #1 Hardware name: HP ProLiant DL360p Gen8, BIOS P71 12/20/2013 RIP: 0010:_raw_spin_lock_irqsave+0x1e/0x40 Code: 85 ff 66 2e 0f 1f 84 00 00 00 00 00 66 66 66 66 90 53 9c 58 66 66 90 66 90 48 89 c3 fa 66 66 90 66 66 90 31 c0 ba 01 00 00 00 <f0> 0f b1 17 0f 94 c2 84 d2 74 05 48 89 d8 5b c3 89 c6 e8 b4 85 8a RSP: 0018:ffffa8d7079a7c08 EFLAGS: 00010046 RAX: 0000000000000000 RBX: 0000000000000202 RCX: ffffa8d7079a7bf8 RDX: 0000000000000001 RSI: ffff93607c990000 RDI: 00000000000000c0 RBP: 0000000000000001 R08: 0000000000000000 R09: ffffffffc08c4dd8 R10: 0000000000000000 R11: 0000000000000001 R12: 00000000000000c0 R13: ffff93607c990000 R14: ffffffffc05a9740 R15: ffffa8d7079a7e98 FS: 00007f1c6ee438c0(0000) GS:ffff93609f6c0000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000000000c0 CR3: 0000000819fca002 CR4: 00000000000606e0 Call Trace: free_netdevs+0x4d/0xe0 [ib_core] ib_dealloc_device+0x51/0xb0 [ib_core] __mlx5_ib_add+0x5e/0x70 [mlx5_ib] mlx5_add_device+0x57/0xe0 [mlx5_core] mlx5_register_interface+0x85/0xc0 [mlx5_core] ? 0xffffffffc0474000 do_one_initcall+0x4e/0x1d4 ? _cond_resched+0x15/0x30 ? kmem_cache_alloc_trace+0x15f/0x1c0 do_init_module+0x5a/0x218 load_module+0x186b/0x1e40 ? m_show+0x1c0/0x1c0 __do_sys_finit_module+0x94/0xe0 do_syscall_64+0x5b/0x180 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Fixes: 8ceb1357b337 ("RDMA/device: Consolidate ib_device per_port data into one place") Signed-off-by: Kamal Heib <kamalheib1@gmail.com> Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.