On 10/30/2014 10:03 AM, Prarit Bhargava wrote: > There have been several times where I have had to rebuild a kernel to > cause a panic when hitting a WARN() in the code in order to get a crash > dump from a system. Sometimes this is easy to do, other times (such as > in the case of a remote admin) it is not trivial to send new images to the > user. > > A much easier method would be a switch to change the WARN() over to a > panic. This makes debugging easier in that I can now test the actual > image the WARN() was seen on and I do not have to engage in remote > debugging. > > This patch adds a panic_on_warn kernel parameter and > /proc/sys/kernel/panic_on_warn calls panic() in the warn_slowpath_common() > path. The function will still print out the location of the warning. > > An example of the panic_on_warn output: > > The first line below is from the WARN_ON() to output the WARN_ON()'s location. > After that the panic() output is displayed. > There is another very valid use for this: many operators would rather a machine shuts down than being potentially compromised either functionally or security-wise. -hpa
