Re: [PATCH v4 5/5] eal: avoid deadlock in async IPC alarm callback

[Stephen Hemminger <stephen@networkplumber.org>]

On Tue, 9 Jun 2026 10:04:22 +0200
"Burakov, Anatoly" <anatoly.burakov@intel.com> wrote:

> On 6/5/2026 4:29 PM, Anatoly Burakov wrote:
> > async_reply_handle_thread_unsafe() can run while holding
> > pending_requests.lock and currently calls rte_eal_alarm_cancel().
> > 
> > rte_eal_alarm_cancel() may spin-wait for an executing callback, which can
> > deadlock if that callback is blocked on the same lock.
> > 
> > Remove callback-side alarm cancellation. It is safe to do so, because any
> > callback triggered without a pending request becomes a noop.
> > 
> > Fixes: daf9bfca717e ("ipc: remove thread for async requests")
> > Cc: stable@dpdk.org
> > 
> > Signed-off-by: Anatoly Burakov <anatoly.burakov@intel.com>
> > ---  
> 
> Okay, the AI review seems to keep flagging issues that are technically 
> true in the patches, but are intentional and do get better once the 
> complete patchset is applied.
> 
> Looks like I need to merge some of the patches or rethink the order in 
> which the fixes are applied to avoid these issues.

The automated AI review has limited scope; it never looks at patch set in total,
and doesn't have tools to read source. That is why for complex things I tend
to start a new session and give it everything. Does much better job then.