kexec load failure introduced by "x86, memblock: Replace e820_/_early string with memblock_"

[caiqian at redhat.com]

----- "Yinghai Lu" <yinghai at kernel.org> wrote:

> On 09/25/2010 11:55 PM, CAI Qian wrote:
> >>
> >> are you kexec from 2.6.35+ to 2.6.36-rc3+?
> > No, both kernels were the same version. I am sorry the above logs
> were misleading that were copy-and-pasted from different kernel
> versions.
> 
> can you check tip instead of next tree?
No dice,
# /sbin/kexec -p '--command-line=ro root=/dev/mapper/VolGroup-lv_root rd_LVM_LV=VolGroup/lv_root rd_LVM_LV=VolGroup/lv_swap rd_NO_LUKS rd_NO_MD rd_NO_DM LANG=en_US.UTF-8 SYSFONT=latarcyrheb-sun16 KEYBOARDTYPE=pc KEYTABLE=us rhgb quiet console=tty0 console=ttyS0,115200 crashkernel=128M irqpoll maxcpus=1 reset_devices cgroup_disable=memory ' --initrd=/boot/initrd-2.6.36-rc5-tip+kdump.img /boot/vmlinuz-2.6.36-rc5-tip+
Could not find a free area of memory of a000 bytes...
locate_hole failed

After reverted the whole memblock commits, it was working again,
7950c407c0288b223a200c1bba8198941599ca37
fb74fb6db91abc3c1ceeb9d2c17b44866a12c63e
f88eff74aa848e58b1ea49768c0bbb874b31357f
27de794365786b4cdc3461ed4e23af2a33f40612
9dc5d569c133819c1ce069ebb1d771c62de32580
4d5cf86ce187c0d3a4cdf233ab0cc6526ccbe01f
88ba088c18457caaf8d2e5f8d36becc731a3d4f6
edbe7d23b4482e7f33179290bcff3b1feae1c5f3
6bcc8176d07f108da3b1af17fb2c0e82c80e948e
b52c17ce854125700c4e19d4427d39bf2504ff63
e82d42be24bd5d75bf6f81045636e6ca95ab55f2
301ff3e88ef9ff4bdb92f36a3e6170fce4c9dd34
72d7c3b33c980843e756681fb4867dc1efd62a76
a9ce6bc15100023b411f8117e53a016d61889800
a587d2daebcd2bc159d4348b6a7b028950a6d803
6f2a75369e7561e800d86927ecd83c970996b21f

If used crashkernel=128M, the /proc/iomem looks like this. It used a huge offset.
00000000-00000fff : reserved
00001000-0009f3ff : System RAM
0009f400-0009ffff : reserved
000f0000-000fffff : reserved
00100000-dfffafff : System RAM
  01000000-0149a733 : Kernel code
  0149a734-01afc46f : Kernel data
  01d9c000-022b18f7 : Kernel bss
dfffb000-dfffffff : reserved
f0000000-f1ffffff : 0000:00:02.0
f2000000-f2000fff : 0000:00:02.0
f2010000-f201ffff : 0000:00:02.0
f2020000-f20200ff : 0000:00:03.0
  f2020000-f20200ff : 8139cp
f2030000-f203ffff : 0000:00:03.0
fec00000-fec003ff : IOAPIC 0
fee00000-fee00fff : Local APIC
fffbc000-ffffffff : reserved
100000000-c9fffffff : System RAM
  c98000000-c9fffffff : Crash kernel

On kernels that are working, it automatically found the offset at 32M.
00000000-0000ffff : reserved
00010000-0009f3ff : System RAM
0009f400-0009ffff : reserved
000f0000-000fffff : reserved
00100000-dfffafff : System RAM
  01000000-014250bf : Kernel code
  014250c0-018aca8f : Kernel data
  01b1f000-01ff7c07 : Kernel bss
  02000000-09ffffff : Crash kernel
dfffb000-dfffffff : reserved
f0000000-f1ffffff : 0000:00:02.0
f2000000-f2000fff : 0000:00:02.0
f2010000-f201ffff : 0000:00:02.0
f2020000-f20200ff : 0000:00:03.0
  f2020000-f20200ff : 8139cp
f2030000-f203ffff : 0000:00:03.0
fec00000-fec003ff : IOAPIC 0
fee00000-fee00fff : Local APIC
fffbc000-ffffffff : reserved
100000000-c9fffffff : System RAM

If specified a fixed offset like crashkernel=128M at 32M, it failed reservation.
initial memory mapped : 0 - 20000000
init_memory_mapping: 0000000000000000-00000000dfffb000
 0000000000 - 00dfe00000 page 2M
 00dfe00000 - 00dfffb000 page 4k
kernel direct mapping tables up to dfffb000 @ 1fffa000-20000000
init_memory_mapping: 0000000100000000-0000000ca0000000
 0100000000 - 0ca0000000 page 2M
kernel direct mapping tables up to ca0000000 @ dffc7000-dfffb000
RAMDISK: 37599000 - 37ff0000
crashkernel reservation failed - memory is in use.

After reverted those commits, it looks like this,
init_memory_mapping: 0000000000000000-00000000dfffb000
 0000000000 - 00dfe00000 page 2M
 00dfe00000 - 00dfffb000 page 4k
kernel direct mapping tables up to dfffb000 @ 16000-1c000
init_memory_mapping: 0000000100000000-0000000ca0000000
 0100000000 - 0ca0000000 page 2M
kernel direct mapping tables up to ca0000000 @ 1a000-4e000
RAMDISK: 375c9000 - 37ff0000
Reserving 128MB of memory at 32MB for crashkernel (System RAM: 51712MB)

I can't tell where the memory at 32MB was used, but after reverted those commits I can see those early reservations information,
Subtract (76 early reservations)
  #1 [0001000000 - 0001ff7c08]   TEXT DATA BSS
  #2 [00375c9000 - 0037ff0000]         RAMDISK
  #3 [0001ff8000 - 0001ff8079]             BRK
  #4 [000009f400 - 00000f7fb0]   BIOS reserved
  #5 [00000f7fb0 - 00000f7fc0]    MP-table mpf
  #6 [00000f822c - 0000100000]   BIOS reserved
  #7 [00000f7fc0 - 00000f822c]    MP-table mpc
  #8 [0000010000 - 0000012000]      TRAMPOLINE
  #9 [0000012000 - 0000016000]     ACPI WAKEUP
  #10 [0000016000 - 000001a000]         PGTABLE
  #11 [000001a000 - 0000049000]         PGTABLE
  #12 [0002000000 - 000a000000]    CRASH KERNEL

But after those commits, those information was gone.