+ Returns non-empty string on success, negarive error code otherwise. Nit: typo, 'negarive' + if (ctx->kdamond) { + if (targetid_is_pid(ctx)) + dbgfs_put_pids(targets, nr_targets); + ret = -EBUSY; + goto unlock_out; I don't understand this block, what does EBUSY mean in this context? + if (sscanf(kbuf, "%s", kbuf) != 1) { + kfree(kbuf); + return -EINVAL; + }Nit, this diverts from other patterns use elsewhere where error conditions that need to free memory use a goto label.