On 10/27/2014 02:05 PM, Jason Baron wrote: > 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. Hmm ... I didn't even think about that. > > So something like 'panic_on_warn' would seem to be more appropriate > in keeping with things like 'panic_on_oops' or 'panic_on_stackoverflow'. I like it a lot better that way too :) I'm changing it to panic_on_warn unless anyone has any strenuous objections. P. > > Thanks, > > -Jason > -- To unsubscribe from this list: send the line "unsubscribe linux-doc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
