On 2024/4/13 11:51, Zhengchao Shao wrote:
> Potential sleeping issue exists in the following processes:
> smc_switch_conns
> spin_lock_bh(&conn->send_lock)
> smc_switch_link_and_count
> smcr_link_put
> __smcr_link_clear
> smc_lgr_put
> __smc_lgr_free
> smc_lgr_free_bufs
> __smc_lgr_free_bufs
> smc_buf_free
> smcr_buf_free
> smcr_buf_unmap_link
> smc_ib_put_memory_region
> ib_dereg_mr
> ib_dereg_mr_user
> mr->device->ops.dereg_mr
> If scheduling exists when the IB driver implements .dereg_mr hook
> function, the bug "scheduling while atomic" will occur. For example,
> cxgb4 and efa driver. Use mutex lock instead of spin lock to fix it.
>
> Fixes: 20c9398d3309 ("net/smc: Resolve the race between SMC-R link access and clear")
> Signed-off-by: Zhengchao Shao <shaozhengchao@xxxxxxxxxx>
> ---
> net/smc/af_smc.c | 2 +-
> net/smc/smc.h | 2 +-
> net/smc/smc_cdc.c | 14 +++++++-------
> net/smc/smc_core.c | 8 ++++----
> net/smc/smc_tx.c | 8 ++++----
> 5 files changed, 17 insertions(+), 17 deletions(-)
>
Hi Zhengchao,
I doubt whether this bug really exists, as efa supports SRD QP while SMC-R relies on RC QP,
cxgb4 is a IWARP adaptor while SMC-R relies on ROCE adaptor.
Thanks,
Guangguan Wang
