um: time-travel/signals: fix ndelay() in interrupt
We should be able to ndelay() from any context, even from an interrupt context! However, this is broken (not functionally, but locking-wise) in time-travel because we'll get into the time-travel code and enable interrupts to handle messages on other time-travel aware subsystems (only virtio for now). Luckily, I've already reworked the time-travel aware signal (interrupt) delivery for suspend/resume to have a time travel handler, which runs directly in the context of the signal and not from the Linux interrupt. In order to fix this time-travel issue then, we need to do a few things: 1) rework the signal handling code to call time-travel handlers (only) if interrupts are disabled but signals aren't blocked, instead of marking it only pending there. This is needed to not deadlock other communication. 2) rework time-travel to not enable interrupts while it's waiting for a message; 3) rework time-travel to not (just) disable interrupts but rather block signals at a lower level while it needs them disabled for communicating with the controller. Finally, since now we can actually spend even virtual time in interrupts-disabled sections, the delay warning when we deliver a time-travel delayed interrupt is no longer valid, things can (and should) now get delayed. Signed-off-by:Johannes Berg <johannes.berg@intel.com> Signed-off-by:
Richard Weinberger <richard@nod.at>
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