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

[Neil Horman]

On Fri, Feb 05, 2010 at 06:45:36PM -0800, Sujit V wrote:
> 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.
> 

Do you use  the mem= kernel command line parameter anywhere?

I ran into something awhile back in which, if memory was
limited in the production kernel with a mem= parameter, the code that setup
/proc/vmcore would still size itself according to the full size of memory, but
error out with -EINVAL after passing the size defined by the previous mem=
command.

Neil

> 
> ---------------------------------------------------------------------------------------
> 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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