printf in interrupt handlers

Ralf Corsepius ralf.corsepius at
Thu Jan 20 11:38:35 UTC 2005

On Thu, 2005-01-20 at 12:09 +0100, Jiri Gaisler wrote:
> Simple question: is printf in interrupt handlers allowed?
Simple answer: No.

More verbose: In general no, this doesn't work. In some (corner-) cases
it works. If it can work, depends on various details of a port/BSP. If
it works, in most cases, this is almost a random accident (or a smart
design ;-) )

Rule of thumb: Use printk - printk is supposed to work in ISRs. If it
doesn't, this would qualify as a bug.


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