Re: [PATCH] memory hotadd fixes [4/5] avoid check in acpi

[KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>]

On Thu, 03 Aug 2006 20:23:46 -0700
keith mannthey <kmannth@us.ibm.com> wrote:

> On Fri, 2006-08-04 at 12:13 +0900, KAMEZAWA Hiroyuki wrote:
> > On Thu, 03 Aug 2006 20:00:08 -0700
> > keith mannthey <kmannth@us.ibm.com> wrote:
> > 
> > 
> > > > >   What protecting is there for calling add_memory on an already present
> > > > > memory range?  
> > > > > 
> > > > For example, considering ia64, which has 1Gbytes section...
> > > 
> > > Maybe 1gb sections is too large?  
> > > 
> > ia64 machines sometimes to have crazy big memory...so 1gb section is requested.
> > Configurable section_size for small machines was rejected in old days.
> 
> My HW supports about 512gb...... 
> 

> What if you add a partial section.  Then online in sysfs and add another
> section?  messy....
Once a section is onlined, it cannot be re-onlined. My patch just helps memory holes
in "a" memory hot add event.
Our firmware team tells us they may create small memory holes in contiguous memory...


>
> > > What keeps 0xa0000000 to 0xa1000000 from being re-onlined by a bad call
> > > to add_memory?
> > 
> > Usual sparsemem's add_memory() checks whether there are sections in
> > sparse_add_one_section(). then add_pages() returns -EEXIST (nothing to do).
> > And ioresouce collision check will finally find collision because 0-0xbffffff
> > resource will conflict with 0xa0000000 to 0xa10000000 area.
> > But, x86_64 's (not sparsemem) add_pages() doen't do collision check, so it panics.
> 
> I have paniced with your 5 patches while doing SPARSMEM....  I think
> your 6th patch address the issues I was seeing.  
> 
Thank you for testing.
BTW, could you send your current config ? looks I should visit source code again..

-Kame



-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/