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During suspend/resume the irq_work is not > used as this has been shown to cause suspend problems for some > hardware. Upon resume, any pending modem control is performed. > > Note: A new __serial8250_clear_IER() is introduced for direct > clearing of UART_IER during console writing (which will not be > holding the port lock for atomic printing or KDB/KGDB). This > allows restoring a lockdep check to serial8250_clear_IER() in > a follow-up commit. > > Signed-off-by: John Ogness I accidently responded to V9, but responding here with the same report for completeness. This change is causing a boot regression for our Tegra20 and Tegra30 platforms. Reverting this on top of -next fixes the issue. Previously with V5 I did not see a boot issue only an issue in suspend. So far I have not had chance to dig any further. Jon -- nvpublic