Messages in this thread | | | Date | Wed, 3 Jun 2020 10:10:26 +0200 | From | Petr Mladek <> | Subject | Re: [PATCH v5 3/4] kdb: Make kdb_printf() console handling more robust |
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On Wed 2020-06-03 12:52:14, Sumit Garg wrote: > While rounding up CPUs via NMIs, its possible that a rounded up CPU > maybe holding a console port lock leading to kgdb master CPU stuck in > a deadlock during invocation of console write operations. A similar > deadlock could also be possible while using synchronous breakpoints. > > So in order to avoid such a deadlock, set oops_in_progress to encourage > the console drivers to disregard their internal spin locks: in the > current calling context the risk of deadlock is a bigger problem than > risks due to re-entering the console driver. We operate directly on > oops_in_progress rather than using bust_spinlocks() because the calls > bust_spinlocks() makes on exit are not appropriate for this calling > context. > > Suggested-by: Petr Mladek <pmladek@suse.com>
I think that this was actually suggested by Sergey.
> Signed-off-by: Sumit Garg <sumit.garg@linaro.org> > Reviewed-by: Douglas Anderson <dianders@chromium.org>
Otherwise, it looks good. With updated suggested by:
Reviewed-by: Petr Mladek <pmladek@suse.com>
Best Regards, Petr
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