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Such disabling can be done by the handler > > itself, or from a remote CPU. > > I don't think the handler itself can legitimately call any of the functions > setting IRQ_DISABLED. Hm, yes, we still have no interrupt handlers that set IRQ_DISABLED, but we will gain one in the next patch, where ns16550_interrupt() will call disable_irq() that does set IRQ_DISABLED. > > Check for IRQ_DISABLED not being set in the loop condition, as to not > > execute the handler if the IRQ has been disabled. > > > > Signed-off-by: Roger Pau Monné > > Preferably with the description adjusted (or it being pointed out what I may > be overlooking): > Reviewed-by: Jan Beulich I'm happy to clarify the commit message to note that while we have no instances ATM, but that future changes might introduce some. Thanks, Roger.