On 12/20/2016 at 11:38 PM, Pratyush Anand wrote: > > > On Monday 19 December 2016 08:10 AM, Dave Young wrote: >> Hi, Pingfan >> >> On 12/19/16 at 10:08am, Pingfan Liu wrote: >>> > kexec-tools always allocates program headers for present cpus. But >>> > when crashing, offline cpus have dummy headers. We do not copy these >>> > dummy notes into ELF file, also have no need of warning on them. >> I still think it is not worth such a fix, if you feel a lot of warnings >> in case large cpu numbers, I think you can change the pr_warn to >> pr_warn_once, we do not care the null cpu notes if it has nothing bad >> to the vmcore. >> > > I agree. Warning is more like information here. May be, we can count the number of times real_sz was 0, and then can print an info at the end in stead of warning, like..."N number of CPUs would have been offline, PT_NOTE entries was absent for them." Well, OTOH the warning may also be due to some user-space misuse, we can't distinguish that without extra information added. Another possible user-space fix would be: Firstly fix kexec-tools to add notes only for online cpus, then utilize udev rules(cpu online/offline events) to automatically trigger kdump kernel reload. Regards, Xunlei
