[PATCH v3 4/4] printk/nmi: Increase the size of NMI buffer and make it configurable
peterz at infradead.org
Fri Dec 18 03:29:02 PST 2015
On Fri, Dec 18, 2015 at 10:18:08AM +0000, Daniel Thompson wrote:
> I'm not entirely sure that this is an improvement.
What I do these days is delete everything in vprintk_emit() and simply
Kill the useless kmsg buffer crap and locking, just pound bytes to the
UART registers without anything in between.
The other semi usable solution is redirecting to trace_printk() and
recovering the trace buffers from your kdump. But I've found that
typically kdump doesn't work anymore if you properly wedge the machine.
So this is very much a second rate solution.
But this globally locked buffer, calling out to console drivers that do
locking and even scheduling, is an unreliable unfixable trainwreck that
I've given up on.
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