kdump cp /proc/vmcore exiting with "Invalid Argument" Error

[Sujit V]

I have integrated the kdump in our linux 2.6.23 based kernel. If I do
echo c > /proc/sysrq-trigger then it boots the kdump kernel & I use
the cp /proc/vmcore /local/crash/vmcore-incomplete

On a new x86 based hardware (32 bit PAE kernel)  the "cp /proc/vmcore
" command exits prematurely.

cp -v /proc/vmcore /local/crash/vmcore-incomplete
      cp: reading `/proc/vmcore': Invalid argument  >>> Error >>

ls -l /local/crash/
total 115588
-r--------    1 0        0        2526724096 Feb  5 03:09 vmcore-incomplete

ls -l /proc/vmcore
-r--------    1 0        0        4153763584 Feb  5 03:16 /proc/vmcore


Every time I trigger kdump the cp command exits after copying
2526724096 bytes. So I thought it might be a file size issue.
Googling pointed out a patch in include/linux/proc_fs.h

struct vmcore {
struct list_head list;
unsigned long long paddr;
- unsigned long size;
+ unsigned long long size;
loff_t offset;

I checked my kernel & it already has this patch.


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IOMEM output

debugshell# cat /proc/iomem
00000000-0009fbff : System RAM
0009fc00-0009ffff : reserved
000a0000-000bffff : Video RAM area
000c0000-000dffff : pnp 00:01
000f0000-000fffff : System ROM
00100000-9e86afff : System RAM
  00200000-006c1cec : Kernel code
  006c1ced-008e68af : Kernel data
  01000000-08ffffff : Crash kernel
9e86b000-9e872fff : ACPI Non-volatile Storage
9e873000-9e874fff : reserved
9e875000-9e8acfff : System RAM
9e8ad000-9e8b3fff : reserved
9e8b4000-9e8d8fff : System RAM
9e8d9000-9e8dbfff : ACPI Tables
9e8dc000-9e8dcfff : System RAM
9e8dd000-9e8eafff : ACPI Tables
9e8eb000-9e8f6fff : System RAM
9e8f7000-9e8f9fff : ACPI Tables
9e8fa000-9e8fafff : ACPI Non-volatile Storage
9e8fb000-9e8fbfff : System RAM
9e8fc000-9e8fcfff : ACPI Tables
9e8fd000-9e902fff : System RAM
9e903000-9e903fff : ACPI Non-volatile Storage
9e904000-9e947fff : System RAM
9e948000-9e948fff : ACPI Tables
9e949000-9e9e6fff : System RAM
9e9e7000-9e9e7fff : reserved
9e9e8000-9e9effff : System RAM
9e9f0000-9e9f2fff : reserved
9e9f3000-9e9f6fff : System RAM
9e9f7000-9e9f9fff : reserved
9e9fa000-9ea09fff : System RAM
9ea0a000-9ea0cfff : reserved
9ea0d000-9ea0efff : System RAM
9ea0f000-9ec0ffff : ACPI Non-volatile Storage
9ec10000-9ec3ffff : System RAM
9ec40000-9ec40fff : ACPI Non-volatile Storage
9ec41000-9ec42fff : System RAM
9ec43000-9ec4cfff : ACPI Non-volatile Storage
9ec4d000-9ec55fff : System RAM
9ec56000-9ec57fff : ACPI Non-volatile Storage
9ec58000-9ec58fff : System RAM
9ec59000-9ec5ffff : ACPI Non-volatile Storage
9ec60000-9ec69fff : System RAM
9ec6a000-9ec6afff : ACPI Non-volatile Storage
9ec6b000-9ec82fff : System RAM
9ec83000-9ec83fff : ACPI Non-volatile Storage
9ec84000-9fbfffff : System RAM
9fc00000-9fffffff : reserved
a0000000-a4ffffff : PCI Bus #03
  a0000000-a1ffffff : 0000:03:00.0
    a0000000-a1ffffff : bnx2
  a2000000-a3ffffff : 0000:03:00.1
    a2000000-a3ffffff : bnx2
a5000000-a5ffffff : PCI Bus #01
a6000000-a70fffff : PCI Bus #02
  a6000000-a6000fff : 0000:02:00.0
a7100000-a80fffff : PCI Bus #03
  a7100000-a711ffff : 0000:03:00.0
  a7120000-a713ffff : 0000:03:00.1
a8100000-a90fffff : PCI Bus #04
a9100000-aa0fffff : PCI Bus #05
aa100000-ab0fffff : PCI Bus #06
ab100000-ac0fffff : PCI Bus #06
ac100000-ad0fffff : PCI Bus #05
ad100000-ae0fffff : PCI Bus #04
ae100000-af0fffff : PCI Bus #02
af100000-b01fffff : PCI Bus #01
  af100000-af11ffff : 0000:01:00.0
    af100000-af11ffff : e1000e
  af120000-af123fff : 0000:01:00.0
    af120000-af123fff : e1000e
b0200000-b0203fff : 0000:00:1b.0
b0204000-b0204fff : 0000:00:1f.6
b0205000-b02053ff : 0000:00:1d.7
  b0205000-b02053ff : ehci_hcd
b0205400-b02057ff : 0000:00:1a.7
  b0205400-b02057ff : ehci_hcd
b0205800-b02058ff : 0000:00:1f.3
e0000000-efffffff : reserved
fec00000-fec00fff : reserved
fed00000-fed003ff : HPET 0
fed13000-fed13fff : pnp 00:01
fed1c000-fed1ffff : pnp 00:01
fee00000-fee00fff : reserved
fff00000-ffffffff : reserved
100000000-15fffffff : System RAM
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