Messages in this thread | | | Subject | Re: [PATCH 4/7] um: time-travel/signals: fix ndelay() in interrupt | From | Johannes Berg <> | Date | Thu, 25 Feb 2021 14:13:33 +0100 |
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On Tue, 2021-02-23 at 16:27 +0100, Johannes Berg wrote: > > +void unblock_signals_hard(void) > +{ > + if (!signals_blocked) > + return; > + > + if (signals_pending && signals_enabled) { > + /* this is a bit inefficient, but that's not really important */ > + block_signals(); > + unblock_signals(); > + } else if (signals_pending & SIGIO_MASK) { > + /* we need to run time-travel handlers even if not enabled */ > + sigio_run_timetravel_handlers(); > + } > + > + signals_blocked = 0; > +}
This is, of course, racy & wrong - we could set signals_pending just after checking it.
Need to make this
{ if (!signals_blocked) return; signals_blocked = 0; barrier();
if (signals_pending && signals_enabled) { ...
Anyway, I need to repost this series, but I'll wait a bit longer for further feedback before that, since I know Arnd and others wanted to take a look at the IOMEM and PCI bits.
johannes
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