Debugging by printing

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Note: This article is currently only a draft and is a part of a series of articles I'm going to publish the next few months - if you want to contribute to it, please feel free to. However it would be nice if you could coordinate your efforts with me

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What this article will be about - ideas

• printk format
• Debug/log levels - dmesg -n /proc/sys/kernel/printk

• printk_ratelimited
• dynamic debug, pr_debug and dev_dbg
• pr_warn and family - see printk.h for details
• early_printk
• printascii, printch and printhex (on ARM only?)
• /dev/kmsg

• Examples - maybe use example module.

References

• Linux Kernel Development, Robert Love, 3rd Edition, Chapter 18 Debugging
• Essential Device Drivers

External links

• http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=blob;f=Documentation/printk-formats.txt;hb=HEAD
• http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=blob;f=Documentation/dynamic-debug-howto.txt;hb=HEAD
• http://en.wikipedia.org/wiki/Printk
• Printk; maybe consolidate