Re: [PATCH AUTOSEL 6.17-6.1] ftrace: Fix softlockup in ftrace_module_enable

On Sat, Oct 25, 2025 at 03:25:45PM -0400, Steven Rostedt wrote:

On Sat, 25 Oct 2025 12:00:16 -0400 Sasha Levin sashal@kernel.org wrote:

...

• The change inserts `cond_resched()` inside the inner iteration over every ftrace record (`kernel/trace/ftrace.c:7538`). That loop holds the ftrace mutex and, for each record, invokes heavy helpers like `test_for_valid_rec()` which in turn calls `kallsyms_lookup()` (`kernel/trace/ftrace.c:4289`). On huge modules (e.g. amdgpu) this can run for tens of milliseconds with preemption disabled, triggering the

It got the "preemption disabled" wrong. Well maybe when running PREEMPT_NONE it is, but the description doesn't imply that.

Thanks for the review! I've been trying a new LLM for part of this series, and it seems to underperform the one I was previously using.