2010/4/12 David VomLehn <dvomlehn@xxxxxxxxx>: > Provide functions for capturing console output for storage. The primary user > is likely to be embedded systems that don't have the storage for core dumps > but do have a need to log kernel panic information for later evaluation. It > offers two main areas of functionality: > > o It can maintain a circular log of console output so that kernel log > messages written before panic() was called can be retrieved to be > added to the failure log. > o A function can be registered to store output from printk() in a > persistent location, such as a reserved location in RAM. Then, > printk() can be used either directly, to print state information, or > indirectly, through standard functions like dump_stack() and > show_regs(). > > During normal operation, we use the circular logging. When we crash, almost > the first thing we do is to switch to storing output. This goes in a memory > buffer that is preserved over reboots. We then write a detailed crash > report using printk() and functions that use printk(). We retrieve the last > n lines of the log before the crash and print it, so that gets captured > in the log, too. > It's very similar to my driver ramoops, have you already seen it? Currently it's in the mm tree, I think it will be included in mainline early. Marco -- To unsubscribe from this list: send the line "unsubscribe linux-embedded" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
