> -----Original Message-----
> From: Kamal Heib <kamalheib1@xxxxxxxxx>
> Sent: 28 October 2021 02:25
> To: linux-rdma@xxxxxxxxxxxxxxx
> Cc: Selvin Xavier <selvin.xavier@xxxxxxxxxxxx>; Doug Ledford
> <dledford@xxxxxxxxxx>; Jason Gunthorpe <jgg@xxxxxxxx>; Leon Romanovsky
> <leon@xxxxxxxxxx>; Aharon Landau <aharonl@xxxxxxxxxx>; Kamal Heib
> <kamalheib1@xxxxxxxxx>
> Subject: [PATCH for-next] RDMA/bnxt_re: Fix kernel panic when trying to access
> bnxt_re_stat_descs
>
> For some reason when introducing 13f30b0fa0a9 commit the "active_pds" and
> "active_ahs" descriptors got dropped, which lead to the following panic when
> trying to access the first entry in the descriptors. Avoid this by return the
> dropped hunks.
>
> bnxt_re: Broadcom NetXtreme-C/E RoCE Driver
> BUG: kernel NULL pointer dereference, address: 0000000000000000
> #PF: supervisor read access in kernel mode
> #PF: error_code(0x0000) - not-present page PGD 0 P4D 0
> Oops: 0000 [#1] SMP PTI
> CPU: 2 PID: 594 Comm: kworker/u32:1 Not tainted 5.15.0-rc6+ #2 Hardware
> name: Dell Inc. PowerEdge R430/0CN7X8, BIOS 2.12.1 12/07/2020
> Workqueue: bnxt_re bnxt_re_task [bnxt_re]
> RIP: 0010:strlen+0x0/0x20
> Code: 48 89 f9 74 09 48 83 c1 01 80 39 00 75 f7 31 d2 44 0f b6 04 16 44 88 04 11
> 48 83 c2 01 45 84 c0 75 ee c3 0f 1f 80 00 00 00 00 <80> 3f 00 74 10 48 89 f8 48
> 83 c0 01 80 31
> RSP: 0018:ffffb25fc47dfbb0 EFLAGS: 00010246
> RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000008100
> RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
> RBP: 0000000000000000 R08: 00000000fffffff4 R09: 0000000000000000
> R10: ffff8a05c71fc028 R11: 0000000000000000 R12: 0000000000000000
> R13: 0000000000000000 R14: 0000000000000000 R15: ffff8a05c3dee800
> FS: 0000000000000000(0000) GS:ffff8a092fc40000(0000)
> knlGS:0000000000000000
> CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> CR2: 0000000000000000 CR3: 000000048d3da001 CR4: 00000000001706e0
> Call Trace:
> kernfs_name_hash+0x12/0x80
> kernfs_find_ns+0x35/0xd0
> kernfs_remove_by_name_ns+0x32/0x90
> remove_files+0x2b/0x60
> create_files+0x1d3/0x1f0
> internal_create_group+0x17b/0x1f0
> internal_create_groups.part.0+0x3d/0xa0
> setup_port+0x180/0x3b0 [ib_core]
> ? __cond_resched+0x16/0x40
> ? kmem_cache_alloc_trace+0x278/0x3d0
> ib_setup_port_attrs+0x99/0x240 [ib_core]
> ib_register_device+0xcc/0x160 [ib_core]
> bnxt_re_task+0xba/0x170 [bnxt_re]
> process_one_work+0x1eb/0x390
> worker_thread+0x53/0x3d0
> ? process_one_work+0x390/0x390
> kthread+0x10f/0x130
> ? set_kthread_struct+0x40/0x40
> ret_from_fork+0x22/0x30
> Modules linked in: bnxt_re kvm ib_uverbs dell_wmi_descriptor rfkill video
> iTCO_wdt iTCO_vendor_support irqbypass dcdbas ib_core ipmi_ssif rapl
> intel_cstate intel_uncore pcspke
> CR2: 0000000000000000
> ---[ end trace b4637e4c4e3001af ]---
> RIP: 0010:strlen+0x0/0x20
> Code: 48 89 f9 74 09 48 83 c1 01 80 39 00 75 f7 31 d2 44 0f b6 04 16 44 88 04 11
> 48 83 c2 01 45 84 c0 75 ee c3 0f 1f 80 00 00 00 00 <80> 3f 00 74 10 48 89 f8 48
> 83 c0 01 80 31
> RSP: 0018:ffffb25fc47dfbb0 EFLAGS: 00010246
> RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000008100
> RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
> RBP: 0000000000000000 R08: 00000000fffffff4 R09: 0000000000000000
> R10: ffff8a05c71fc028 R11: 0000000000000000 R12: 0000000000000000
> R13: 0000000000000000 R14: 0000000000000000 R15: ffff8a05c3dee800
> FS: 0000000000000000(0000) GS:ffff8a092fc40000(0000)
> knlGS:0000000000000000
> CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> CR2: 0000000000000000 CR3: 000000048d3da001 CR4: 00000000001706e0
> Kernel panic - not syncing: Fatal exception Kernel Offset: 0x400000 from
> 0xffffffff81000000 (relocation range: 0xffffffff80000000-0xffffffffbfffffff)
> ---[ end Kernel panic - not syncing: Fatal exception ]---
>
> Fixes: 13f30b0fa0a9 ("RDMA/counter: Add a descriptor in struct
> rdma_hw_stats")
> Signed-off-by: Kamal Heib <kamalheib1@xxxxxxxxx>
> ---
> drivers/infiniband/hw/bnxt_re/hw_counters.c | 2 ++
> 1 file changed, 2 insertions(+)
>
> diff --git a/drivers/infiniband/hw/bnxt_re/hw_counters.c
> b/drivers/infiniband/hw/bnxt_re/hw_counters.c
> index 78ca6dfd182b..825d512799d9 100644
> --- a/drivers/infiniband/hw/bnxt_re/hw_counters.c
> +++ b/drivers/infiniband/hw/bnxt_re/hw_counters.c
> @@ -58,6 +58,8 @@
> #include "hw_counters.h"
>
> static const struct rdma_stat_desc bnxt_re_stat_descs[] = {
> + [BNXT_RE_ACTIVE_PD].name = "active_pds",
> + [BNXT_RE_ACTIVE_AH].name = "active_ahs",
> [BNXT_RE_ACTIVE_QP].name = "active_qps",
> [BNXT_RE_ACTIVE_SRQ].name = "active_srqs",
> [BNXT_RE_ACTIVE_CQ].name = "active_cqs",
> --
Looks good to me.
Reviewed-By: Devesh Sharma <devesh.s.sharma@xxxxxxxxxx>
> 2.31.1
