Hi Guangguan: Thank you for your review. When I used the hns driver, I ran into the problem of "scheduling while atomic". But the problem was tested on the 5.10 kernel branch, and I'm still trying to reproduce it using the mainline. Zhengchao Shao On 2024/4/17 16:00, Guangguan Wang wrote:
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
