Re: [PATCH 4.14 023/159] mm/sparsemem: Allocate mem_section at runtime for CONFIG_SPARSEMEM_EXTREME=y

[Baoquan He]

On 02/07/18 at 08:00pm, Dou Liyang wrote:
> Hi Kirill,Mike
> 
> At 02/07/2018 06:45 PM, Mike Galbraith wrote:
> > On Wed, 2018-02-07 at 13:41 +0300, Kirill A. Shutemov wrote:
> > > On Wed, Feb 07, 2018 at 05:25:05PM +0800, Dou Liyang wrote:
> > > > Hi All,
> > > > 
> > > > I met the makedumpfile failed in the upstream kernel which contained
> > > > this patch. Did I missed something else?
> > > 
> > > None I'm aware of.
> > > 
> > > Is there a reason to suspect that the issue is related to the bug this patch
> > > fixed?
> > 
> 
> I did a contrastive test by my colleagues Indoh's suggestion.
> 
> Revert your two commits:
> 
> commit 83e3c48729d9ebb7af5a31a504f3fd6aff0348c4
> Author: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx>
> Date:   Fri Sep 29 17:08:16 2017 +0300
> 
> commit 629a359bdb0e0652a8227b4ff3125431995fec6e
> Author: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx>
> Date:   Tue Nov 7 11:33:37 2017 +0300
> 
> ...and keep others unchanged, the makedumpfile works well.
> 
> > Still works fine for me with .today.  Box is only 16GB desktop box though.
> > 
> Btw, In the upstream kernel which contained this patch, I did two tests:
> 
>  1) use the makedumpfile as core_collector in /etc/kdump.conf, then
> trigger the process of kdump by echo 1 >/proc/sysrq-trigger, the
> makedumpfile works well and I can get the vmcore file.
> 
>      ......It is OK
> 
>  2) use cp as core_collector, do the same operation to get the vmcore file.
> then use makedumpfile to do like above:
> 
>     [douly@localhost code]$ ./makedumpfile -d 31 --message-level 31 -x
> vmlinux_4.15+ vmcore_4.15+_from_cp_command vmcore_4.15+

Oh, then please ignore my previous comment. Adding '-D' can give more
debugging message.

> 
>     ......It causes makedumpfile failed.
> 
> 
> Thanks,
> 	dou.
> 
> > 	-Mike
> > 
> > 
> > 
> 
>