Hi Prarit, On 10/24/2014 08:53 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.panic_on_stackoverflow > > A much easier method would be a switch to change the WARN() over to a > BUG(). 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 bug_on_warn kernel parameter and > /proc/sys/kernel/bug_on_warn calls BUG() in the warn_slowpath_common() > path. The function will still print out the location of the warning. > > An example of the bug_on_warn output: > > The first line below is from the WARN_ON() to output the WARN_ON()'s location. > After that the new BUG() call is displayed. > > WARNING: CPU: 27 PID: 3204 at > /home/rhel7/redhat/debug/dummy-module/dummy-module.c:25 init_dummy+0x28/0x30 > [dummy_module]() > bug_on_warn set, calling BUG()... > ------------[ cut here ]------------ > kernel BUG at kernel/panic.c:434! Seems reasonable-I'm wondering why you just don't call panic() in this case. The BUG() call at line '434' doesn't at anything since its just being called from panic.c. So something like 'panic_on_warn' would seem to be more appropriate in keeping with things like 'panic_on_oops' or 'panic_on_stackoverflow'. Thanks, -Jason
