[Crash-utility] kmem: WARNING: cannot find mem_map page for address

[Bruce Korb]

Hi Dave,

On Tue, Dec 18, 2012 at 2:12 PM, Dave Anderson <anderson at redhat.com> wrote:
>> > crash> p mem_section[0x400]
>> > $13 = (struct mem_section *) 0xffffffff81a26658
>> > crash> p mem_section[0x400][0x0]
>> > $14 = {
>> >   section_mem_map = 0xffffffff81a26630,
>> >   pageblock_flags = 0xffffffff81a26680
>> > }

I think I did show the memory section.  But it is understandable if
you missed it.
I plodded my way through the macros to figure out that the flag value of

> crash> p $tp->page->flags
> $9 = 0x200000000000000

ultimately maps to indexes of 0x400 and 0.
(47 bit shift for first index)
There are only two fields because of kernel build options.

>  crash> struct mem_section ffff88021e5eb000 -x
>  struct mem_section {
>    section_mem_map = 0xffffea0000000003,
>    pageblock_flags = 0xffff88021e1eaa00,

Since your example has upper 4 bytes of 0xffffea00, similar to
the (cfs_page_t *) 0xffffea001bb1d1e8 page address I am trying to understand,
maybe the 0xffffffff81a26630 address is bogus?

>    page_cgroup = 0xffff880215880000,
>    pad = 0x0