On Tue, Aug 26, 2025 at 04:44:42PM +0800, Liu Jian wrote:
> BUG: kernel NULL pointer dereference, address: 00000000000002ec
> PGD 0 P4D 0
> Oops: Oops: 0000 [#1] SMP PTI
> CPU: 28 UID: 0 PID: 343 Comm: kworker/28:1 Kdump: loaded Tainted: G OE 6.17.0-rc2+ #9 NONE
> Tainted: [O]=OOT_MODULE, [E]=UNSIGNED_MODULE
> Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.15.0-1 04/01/2014
> Workqueue: smc_hs_wq smc_listen_work [smc]
> RIP: 0010:smc_ib_is_sg_need_sync+0x9e/0xd0 [smc]
>
> diff --git a/net/smc/smc_ib.c b/net/smc/smc_ib.c
> index 53828833a3f7..85501d2c1f1b 100644
> --- a/net/smc/smc_ib.c
> +++ b/net/smc/smc_ib.c
> @@ -747,6 +747,8 @@ bool smc_ib_is_sg_need_sync(struct smc_link *lnk,
> buf_slot->sgt[lnk->link_idx].nents, i) {
> if (!sg_dma_len(sg))
> break;
> + if (!lnk->smcibdev->ibdev->dma_device)
> + break;
Why check it inside the loop?
