Re: [PATCH v5 06/18] tracing/remotes: Add dmesg tracefs file
From: sashiko-bot@kernel.org
Date: 2026-08-12 16:42:57
Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider: - [Medium] When CONFIG_PRINTK is disabled, dmesg redirection stalls the event iterator perpetually because `pr_info` returns 0. --
--- Patch [6]: [PATCH v5 06/18] tracing/remotes: Add dmesg tracefs file ---commit b41c280df86084ff7600dad9b61a6fa3dbbdf1dd Author: Vincent Donnefort [off-list ref] tracing/remotes: Add dmesg tracefs file When enabled, the dmesg tracefs file enables the redirection of all events to dmesg. This is similar to tp_printk.
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diff --git a/kernel/trace/trace_remote.c b/kernel/trace/trace_remote.c index 1fbe2f3f20e99..3a5e0d84c1722 100644 --- a/kernel/trace/trace_remote.c +++ b/kernel/trace/trace_remote.c
[ ... ]
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@@ -882,6 +908,87 @@ static const struct file_operations trace_fops = { .release = trace_release, }; +static bool trace_remote_do_dmesg(struct trace_remote *remote) +{ + struct trace_remote_iterator *iter = smp_load_acquire(&remote->dmesg); + unsigned int max_events = 1000; + + if (!iter) + return false; + + trace_remote_iter_read_start(iter); + + while (trace_remote_iter_read_event(iter)) { + trace_seq_init(&iter->seq); + + trace_remote_iter_print_event(iter); + trace_seq_putc(&iter->seq, 0); + if (!pr_info("%s", seq_buf_str(&iter->seq.seq))) + break;
[Severity: Medium] When CONFIG_PRINTK is disabled, pr_info() is defined as no_printk, which unconditionally returns 0. Does this cause the loop to always break early and skip the call to trace_remote_iter_move() below? If so, it appears the background polling work would continually fail to drain the trace remote buffer and run periodically without doing any work, as the iterator never advances.
+ + trace_remote_iter_move(iter); + + if (!(--max_events)) + break; + } + + trace_remote_iter_read_finished(iter); + + return !max_events; +}
-- Sashiko AI review · https://sashiko.dev/#/patchset/20260812161340.2417322-1-vdonnefort@google.com?part=6