On Wed, 8 Jul 2026 09:18:04 -0400
Steven Rostedt [off-list ref] wrote:

On Wed, 8 Jul 2026 21:37:53 +0900
Jeongho Choi [off-list ref] wrote:

quoted

The code at the WARN location mentioned in the log above is as follows.

7374                 if (WARN_ONCE(trys++ > 100, "Error: Too many
  tries to read user space"))
7375                         return NULL;

This happens when something forces a schedule.

quoted

Our current analysis is as follows:

In the Gmail process, during a low memory situation, LMKD writes strings
to /sys/kernel/tracing/trace_marker for systrace recording. At the same
time, it broadcasts a sigkill due to low memory, which is causing the
LMKD trace marker operation to stall.

Can you see what is being scheduled in? Perhaps use the persistent ring
buffer (if you can) and enable sched_switch tracepoint in it.

Nit: If the device just caused oom and not crash/reboot the kernel, you can
just use normal ring buffer (or perfetto).

Thanks, 

-- 
Masami Hiramatsu (Google) [off-list ref]