Hello, Peter, Ingo and Will.
(Q1) Can we change the capacity using kernel config?
(Q2) If we can change the capacity, is it OK to specify these constants
independently? (In other words, is there inter-dependency among
these constants?)
(Q3) Do you think that we can extend lockdep to be used as a tool for auditing
locks held in kernel space and rebuilding lock dependency map in user
space?
On 2020/07/25 14:23, Tetsuo Handa wrote:
>> Also somebody may use it to _reduce_ size of the table for a smaller kernel.
>
> Maybe. But my feeling is that it is very rare that the kernel actually
> deadlocks
> as soon as lockdep warned the possibility of deadlock.
>
> Since syzbot runs many instances in parallel, a lot of CPU resource is spent
> for
> checking the same dependency tree. However, the possibility of deadlock can be
> warned for only locks held within each kernel boot, and it is impossible to
> hold
> all locks with one kernel boot.
>
> Then, it might be nice if lockdep can audit only "which lock was held from
> which
> context and what backtrace" and export that log like KCOV data (instead of
> evaluating
> the possibility of deadlock), and rebuild the whole dependency (and evaluate
> the
> possibility of deadlock) across multiple kernel boots in userspace.
