Re: [PATCH for-next v2] RDMA/rxe: Fix mr->map double free

[Jason Gunthorpe]

On Sun, Oct 30, 2022 at 03:04:33AM +0000, Li Zhijian wrote:
> rxe_mr_cleanup() which tries to free mr->map again will be called
> when rxe_mr_init_user() fails.
> 
> [43895.939883] CPU: 0 PID: 4917 Comm: rdma_flush_serv Kdump: loaded Not tainted 6.1.0-rc1-roce-flush+ #25
> [43895.942341] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014
> [43895.945208] Call Trace:
> [43895.946130]  <TASK>
> [43895.946931]  dump_stack_lvl+0x45/0x5d
> [43895.948049]  panic+0x19e/0x349
> [43895.949010]  ? panic_print_sys_info.part.0+0x77/0x77
> [43895.950356]  ? asm_sysvec_apic_timer_interrupt+0x16/0x20
> [43895.952589]  ? preempt_count_sub+0x14/0xc0
> [43895.953809]  end_report.part.0+0x54/0x7c
> [43895.954993]  ? rxe_mr_cleanup+0x9d/0xf0 [rdma_rxe]
> [43895.956406]  kasan_report.cold+0xa/0xf
> [43895.957668]  ? rxe_mr_cleanup+0x9d/0xf0 [rdma_rxe]
> [43895.959090]  rxe_mr_cleanup+0x9d/0xf0 [rdma_rxe]
> [43895.960502]  __rxe_cleanup+0x10a/0x1e0 [rdma_rxe]
> [43895.961983]  rxe_reg_user_mr+0xb7/0xd0 [rdma_rxe]
> [43895.963456]  ib_uverbs_reg_mr+0x26a/0x480 [ib_uverbs]
> [43895.964921]  ? __lock_acquire+0x876/0x31e0
> [43895.966182]  ? ib_uverbs_ex_create_wq+0x630/0x630 [ib_uverbs]
> [43895.967739]  ? uverbs_fill_udata+0x1c6/0x330 [ib_uverbs]
> [43895.969204]  ib_uverbs_handler_UVERBS_METHOD_INVOKE_WRITE+0x1a2/0x250 [ib_uverbs]
> [43895.971126]  ? ib_uverbs_handler_UVERBS_METHOD_QUERY_CONTEXT+0x1a0/0x1a0 [ib_uverbs]
> [43895.973094]  ? ib_uverbs_handler_UVERBS_METHOD_QUERY_CONTEXT+0x1a0/0x1a0 [ib_uverbs]
> [43895.975096]  ? uverbs_fill_udata+0x25f/0x330 [ib_uverbs]
> [43895.976466]  ib_uverbs_cmd_verbs+0x1397/0x15a0 [ib_uverbs]
> [43895.977930]  ? ib_uverbs_handler_UVERBS_METHOD_QUERY_CONTEXT+0x1a0/0x1a0 [ib_uverbs]
> [43895.979937]  ? uverbs_fill_udata+0x330/0x330 [ib_uverbs]

Please dont include timestamps in commit messages

> @@ -163,9 +163,8 @@ int rxe_mr_init_user(struct rxe_dev *rxe, u64 start, u64 length, u64 iova,
>  				pr_warn("%s: Unable to get virtual address\n",
>  						__func__);
>  				err = -ENOMEM;
> -				goto err_cleanup_map;
> +				goto err_release_umem;
>  			}
> -

page_address() fails if this is a highmem system and the page hasn't
been kmap'd yet. So the right thing to do is to use kmap..

But this looks right, so applied to for-next

Thanks,
Jason