On Fri, Nov 15, 2013 at 06:41:52PM +0900, HATAYAMA Daisuke wrote: [..] > >Given the fact that hpa does not like fixing it in kernel. We are left > >with option of fixing it in following places. > > > >- Drop partial pages in kexec-tools > >- Drop partial pages in makeudmpfile. > >- Read partial pages using read() interface in makedumpfile > >- Modify /proc/vmcore to copy partial pages in second kernel's memory. > > > >It is not clear to me that partial pages are really useful. So I want > >to avoid modifying /proc/vmcore to deal with partial pages and increase > >complexity. > > > >So fixing makedumpfile (either option2 or option 3) seems least risky > >to me. In fact I would say let us keep it simple and truncate partial > >pages in makedumpfile to keep it simple. And look at option 3 once we > >have a strong use case for partial pages. > > > >What do you think? > > > > As you say, it's not clear that partial pages are really useful, but on > the other hand, it seems to me not clear that they are really useless. > I think we should get them as long as we have access to them. > > It seems best to me the option 3). Switching between read and mmap would > be not so complex and also it's by far flexible in makedumpfile than in > kernel. Ok, I am fine with option 3. It is more complicated option but safe option. Is there any chance that you could look into fixing this. I have no experience writing code for makedumpfile. Thanks Vivek
