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charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-nvme" Errors-To: linux-nvme-bounces+linux-nvme=archiver.kernel.org@lists.infradead.org On 12/12/2019 01:28 AM, Christoph Hellwig wrote: >> +static ssize_t nvmet_subsys_attr_model_show(struct config_item *item, >> + char *page) >> +{ >> + struct nvmet_subsys *subsys = to_subsys(item); >> + >> + return snprintf(page, PAGE_SIZE, "%s\n", >> + nvmet_model_number(subsys)); > > This whole statements easily fits onto a single line. > >> + down_write(&nvmet_config_sem); >> + kfree(subsys->model); >> + subsys->model = tmp_model; >> + up_write(&nvmet_config_sem); > > Without using something like RCU this means all users of ->model > now need to take nvmet_config_sem. I guess using RCU here is simple > enough - just use rcu_swap_protected and kfree_rcu here. > Since this is not into the fast path subsys->lock can be used for that ? (and in the helper nvmet_model_number() ?) OR Is there a specific reason we need to use rcu ? Also similar pattern(use of nvmet_config_sem) exists for the subsys->serial, does that mean whatever fix we do for subsys->model that needs to be repeated for subsys->serial ? _______________________________________________ linux-nvme mailing list linux-nvme@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-nvme