Re: [PATCH for-rc 3/4] IB/hfi1: Fix probe time panic when AIP is enabled with a buggy BIOS

[Jason Gunthorpe <jgg@nvidia.com>]

On Mon, Mar 29, 2021 at 09:48:19AM -0400, dennis.dalessandro@cornelisnetworks.com wrote:
> From: Mike Marciniszyn <mike.marciniszyn@cornelisnetworks.com>
> 
> A panic can result when AIP is enabled:
> 
> [ 8.644728] BUG: unable to handle kernel NULL pointer dereference at 000000000000000
> [ 8.657708] PGD 0 P4D 0
> [ 8.664488] Oops: 0000 1 SMP PTI
> [ 8.672190] CPU: 70 PID: 981 Comm: systemd-udevd Tainted: G OE --------- - - 4.18.0-240.el8.x86_64 #1
> [ 8.687916] Hardware name: Intel Corporation S2600KP/S2600KP, BIOS SE5C610.86B.01.01.0005.101720141054 10/17/2014
> [ 8.703340] RIP: 0010:__bitmap_and+0x1b/0x70
> [ 8.741702] RSP: 0018:ffff99aa0845f9f0 EFLAGS: 00010246
> [ 8.751757] RAX: 0000000000000000 RBX: ffff8d5a6fc18000 RCX: 0000000000000048
> [ 8.764203] RDX: 0000000000000000 RSI: ffffffffc06336f0 RDI: ffff8d5a8fa67750
> [ 8.776990] RBP: 0000000000000079 R08: 0000000fffffffff R09: 0000000000000000
> [ 8.789768] R10: 0000000000000000 R11: 0000000000000001 R12: ffffffffc06336f0
> [ 8.802007] R13: 00000000000000a0 R14: ffff8d5a6fc18000 R15: 0000000000000003
> [ 8.814317] FS: 00007fec137a5980(0000) GS:ffff8d5a9fa80000(0000) knlGS:0000000000000000
> [ 8.827629] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> [ 8.838309] CR2: 0000000000000000 CR3: 0000000a04b48002 CR4: 00000000001606e0
> [ 8.850502] Call Trace:
> [ 8.857950] hfi1_num_netdev_contexts+0x7c/0x110 [hfi1]
> [ 8.868295] hfi1_init_dd+0xd7f/0x1a90 [hfi1]
> [ 8.877681] ? pci_bus_read_config_dword+0x49/0x70
> [ 8.887567] ? pci_mmcfg_read+0x3e/0xe0
> [ 8.896797] do_init_one.isra.18+0x336/0x640 [hfi1]
> [ 8.906958] local_pci_probe+0x41/0x90
> [ 8.915784] pci_device_probe+0x105/0x1c0
> [ 8.925002] really_probe+0x212/0x440
> [ 8.933687] driver_probe_device+0x49/0xc0
> [ 8.942918] device_driver_attach+0x50/0x60
> [ 8.952553] __driver_attach+0x61/0x130
> [ 8.961553] ? device_driver_attach+0x60/0x60
> [ 8.971122] bus_for_each_dev+0x77/0xc0
> [ 8.979912] ? klist_add_tail+0x3b/0x70
> [ 8.988886] bus_add_driver+0x14d/0x1e0
> [ 8.998175] ? dev_init+0x10b/0x10b [hfi1]
> [ 9.007531] driver_register+0x6b/0xb0
> [ 9.016757] ? dev_init+0x10b/0x10b [hfi1]
> [ 9.026220] hfi1_mod_init+0x1e6/0x20a [hfi1]
> [ 9.035601] do_one_initcall+0x46/0x1c3
> [ 9.043958] ? free_unref_page_commit+0x91/0x100
> [ 9.053460] ? _cond_resched+0x15/0x30
> [ 9.062426] ? kmem_cache_alloc_trace+0x140/0x1c0
> [ 9.071982] do_init_module+0x5a/0x220
> [ 9.080574] load_module+0x14b4/0x17e0
> [ 9.088911] ? __do_sys_finit_module+0xa8/0x110
> [ 9.098231] __do_sys_finit_module+0xa8/0x110
> [ 9.107307] do_syscall_64+0x5b/0x1a0
> 
> The issue happens when pcibus_to_node() returns NO_NUMA_NODE.
> 
> Fix this issue by moving the initialization of dd->node to hfi1_devdata
> allocation and remove the other pcibus_to_node() calls in the probe
> path and use dd->node instead.
> 
> Affinity logic is adjusted to use a new field dd->affinity_entry
> as a guard instead of dd->node.
> 
> Fixes: 4730f4a6c6b2 ("IB/hfi1: Activate the dummy netdev")
> Cc: stable@vger.kernel.org
> Signed-off-by: Mike Marciniszyn <mike.marciniszyn@cornelisnetworks.com>
> Signed-off-by: Dennis Dalessandro <dennis.dalessandro@cornelisnetworks.com>
> ---
>  drivers/infiniband/hw/hfi1/affinity.c  | 21 +++++----------------
>  drivers/infiniband/hw/hfi1/hfi.h       |  1 +
>  drivers/infiniband/hw/hfi1/init.c      | 10 +++++++++-
>  drivers/infiniband/hw/hfi1/netdev_rx.c |  3 +--
>  4 files changed, 16 insertions(+), 19 deletions(-)

Applied to for-rc

Thanks,
Jason