On Tue, 2020-12-22 at 14:12 +0800, Can Guo wrote: > > > + return -EOPNOTSUPP; > > > + > > > + if (kstrtouint(buf, 0, &wb_enable)) > > > + return -EINVAL; > > > + > > > + if (wb_enable != 0 && wb_enable != 1) > > > + return -EINVAL; > > > + > > > + pm_runtime_get_sync(hba->dev); > > > + res = ufshcd_wb_ctrl(hba, wb_enable); > > > > May this operation race with UFS shutdown flow? > > > > To be more clear, ufshcd_wb_ctrl() here may be executed after host > > clock > > is disabled by shutdown flow? > > > > If yes, we need to avoid it. > > I have the same doubt - can user still access sysfs nodes after > system > starts to run shutdown routines? If yes, then we need to remove all > UFS > sysfs nodes in ufshcd_shutdown(). > No, we shouldn't do in this way, user space complains this. I think the nodes in the sysfs can be shileded write, but the nodes shouldn't be flash of its presence frequently. Thanks, Bean > Thanks, > > Can Guo.
