Help: strange messages from kernel on IA64 platform

Help: strange messages from kernel on IA64 platform

[Ju, Seokmann]

Hi,

During communication in between application and megaraid driver via
IOCTL, the system displays messages which are not easy to track down.
Following is one of the messages and same messages with different values
are poping up regularly.
---
Kernel unaligned access to 0xe00000007f3d80dc ip=0xa0000002000373b1
---

I understand the kernel is complaining about the address which is not
aligned and, found the message is coming from function
'ia64_handle_unaligned()' in the arch/ia64/kernel/unaligned.c.
But, I couldn't find who is calling this function and further details of
reasons.

Where should I start to figure out it?

Thank you,

Seokmann

Help: strange messages from kernel on IA64 platform

[Ju, Seokmann]

Hi,

During communication in between application and megaraid driver via
IOCTL, the system displays messages which are not easy to track down.
Following is one of the messages and same messages with different values
are poping up regularly.
---
Kernel unaligned access to 0xe00000007f3d80dc ip=0xa0000002000373b1
---

I understand the kernel is complaining about the address which is not
aligned and, found the message is coming from function
'ia64_handle_unaligned()' in the arch/ia64/kernel/unaligned.c.
But, I couldn't find who is calling this function and further details of
reasons.

Where should I start to figure out it?

Thank you,

Seokmann

Re: Help: strange messages from kernel on IA64 platform

[Chase Venters]

On Tue, 16 May 2006, Ju, Seokmann wrote:

> Hi,
>
> During communication in between application and megaraid driver via
> IOCTL, the system displays messages which are not easy to track down.
> Following is one of the messages and same messages with different values
> are poping up regularly.
> ---
> Kernel unaligned access to 0xe00000007f3d80dc ip=0xa0000002000373b1
> ---
>
> I understand the kernel is complaining about the address which is not
> aligned and, found the message is coming from function
> 'ia64_handle_unaligned()' in the arch/ia64/kernel/unaligned.c.
> But, I couldn't find who is calling this function and further details of
> reasons.
>
> Where should I start to figure out it?

It's a trap, which means the CPU is effectively calling that function. My 
best suggestion is to figure out what data is at 0xe00000007f3d80dc and 
what instructions are at 0xa0000002000373b1.

> Thank you,
>
> Seokmann

Thanks,
Chase

RE: Help: strange messages from kernel on IA64 platform

[Ju, Seokmann]

Hi,

Tuesday, May 16, 2006 5:00 PM, Chase Venters wrote:
> It's a trap, which means the CPU is effectively calling that 
> function.
O.K, that's why...
Then, Is there anyway to look up trap table that the CPU has?
> My best suggestion is to figure out what data is at 
> 0xe00000007f3d80dc and 
> what instructions are at 0xa0000002000373b1.
I will try as you suggested.
Thank you very much for comment.

Regards,

> -----Original Message-----
> From: Chase Venters [mailto:chase.venters@clientec.com] 
> Sent: Tuesday, May 16, 2006 5:00 PM
> To: Ju, Seokmann
> Cc: Linux Kernel Mailing List; linux-scsi@vger.kernel.org
> Subject: Re: Help: strange messages from kernel on IA64 platform
> 
> On Tue, 16 May 2006, Ju, Seokmann wrote:
> 
> > Hi,
> >
> > During communication in between application and megaraid driver via
> > IOCTL, the system displays messages which are not easy to 
> track down.
> > Following is one of the messages and same messages with 
> different values
> > are poping up regularly.
> > ---
> > Kernel unaligned access to 0xe00000007f3d80dc ip=0xa0000002000373b1
> > ---
> >
> > I understand the kernel is complaining about the address 
> which is not
> > aligned and, found the message is coming from function
> > 'ia64_handle_unaligned()' in the arch/ia64/kernel/unaligned.c.
> > But, I couldn't find who is calling this function and 
> further details of
> > reasons.
> >
> > Where should I start to figure out it?
> 
> It's a trap, which means the CPU is effectively calling that 
> function. My 
> best suggestion is to figure out what data is at 
> 0xe00000007f3d80dc and 
> what instructions are at 0xa0000002000373b1.
> 
> > Thank you,
> >
> > Seokmann
> 
> Thanks,
> Chase
> 

RE: Help: strange messages from kernel on IA64 platform

[Ju, Seokmann]

Hi,

Tuesday, May 16, 2006 5:00 PM, Chase Venters wrote:
> It's a trap, which means the CPU is effectively calling that 
> function.
O.K, that's why...
Then, Is there anyway to look up trap table that the CPU has?
> My best suggestion is to figure out what data is at 
> 0xe00000007f3d80dc and 
> what instructions are at 0xa0000002000373b1.
I will try as you suggested.
Thank you very much for comment.

Regards,

> -----Original Message-----
> From: Chase Venters [mailto:chase.venters@clientec.com] 
> Sent: Tuesday, May 16, 2006 5:00 PM
> To: Ju, Seokmann
> Cc: Linux Kernel Mailing List; linux-scsi@vger.kernel.org
> Subject: Re: Help: strange messages from kernel on IA64 platform
> 
> On Tue, 16 May 2006, Ju, Seokmann wrote:
> 
> > Hi,
> >
> > During communication in between application and megaraid driver via
> > IOCTL, the system displays messages which are not easy to 
> track down.
> > Following is one of the messages and same messages with 
> different values
> > are poping up regularly.
> > ---
> > Kernel unaligned access to 0xe00000007f3d80dc ip=0xa0000002000373b1
> > ---
> >
> > I understand the kernel is complaining about the address 
> which is not
> > aligned and, found the message is coming from function
> > 'ia64_handle_unaligned()' in the arch/ia64/kernel/unaligned.c.
> > But, I couldn't find who is calling this function and 
> further details of
> > reasons.
> >
> > Where should I start to figure out it?
> 
> It's a trap, which means the CPU is effectively calling that 
> function. My 
> best suggestion is to figure out what data is at 
> 0xe00000007f3d80dc and 
> what instructions are at 0xa0000002000373b1.
> 
> > Thank you,
> >
> > Seokmann
> 
> Thanks,
> Chase
> 

RE: Help: strange messages from kernel on IA64 platform

["Döhr, Markus ICC-H"]

> During communication in between application and megaraid 
> driver via IOCTL, the system displays messages which are not 
> easy to track down.
> Following is one of the messages and same messages with 
> different values are poping up regularly.
> ---
> Kernel unaligned access to 0xe00000007f3d80dc ip=0xa0000002000373b1
> ---

We have this message too on our main database server; the interesting part
is, that the application, which triggers this error, is a database (MaxDB)
and the process name is "kernel"... Just to avoid confusion: look if there's
an application with such name running on your system.


Greetz,


SIEGENIA-AUBI KG
Informationswesen
 
i.A.
 
Markus Döhr
SAP-CC/BC, SAPDB-DBA

Tel.:	 +49 6503 917-152
Fax:	 +49 6503 917-7152
E-Mail: markus.doehr@siegenia-aubi.com
Internet: http://www.siegenia-aubi.com 
  
-
To unsubscribe from this list: send the line "unsubscribe linux-scsi" in
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RE: Help: strange messages from kernel on IA64 platform

["Döhr, Markus ICC-H"]

> During communication in between application and megaraid 
> driver via IOCTL, the system displays messages which are not 
> easy to track down.
> Following is one of the messages and same messages with 
> different values are poping up regularly.
> ---
> Kernel unaligned access to 0xe00000007f3d80dc ip=0xa0000002000373b1
> ---

We have this message too on our main database server; the interesting part
is, that the application, which triggers this error, is a database (MaxDB)
and the process name is "kernel"... Just to avoid confusion: look if there's
an application with such name running on your system.


Greetz,


SIEGENIA-AUBI KG
Informationswesen
 
i.A.
 
Markus Döhr
SAP-CC/BC, SAPDB-DBA

Tel.:	 +49 6503 917-152
Fax:	 +49 6503 917-7152
E-Mail: markus.doehr@siegenia-aubi.com
Internet: http://www.siegenia-aubi.com 
  

RE: Help: strange messages from kernel on IA64 platform

[Ju, Seokmann]

Hi,

Tuesday, May 16, 2006 5:20 PM, "Döhr, Markus ICC-H" wrote:
> We have this message too on our main database server; the 
> interesting part
> is, that the application, which triggers this error, is a 
> database (MaxDB)
> and the process name is "kernel"... Just to avoid confusion: 
> look if there's
> an application with such name running on your system.
I quickly looked at the system with 'ps' command.
It seems there is no such process which starting its name with "kernel.." on the system.
Thank you for your comment.

Regards,

> -----Original Message-----
> From: "Döhr, Markus ICC-H" [mailto:Markus.Doehr@siegenia-aubi.com] 
> Sent: Tuesday, May 16, 2006 5:20 PM
> To: Ju, Seokmann; Linux Kernel Mailing List
> Cc: linux-scsi@vger.kernel.org
> Subject: RE: Help: strange messages from kernel on IA64 platform
> 
> > During communication in between application and megaraid 
> > driver via IOCTL, the system displays messages which are not 
> > easy to track down.
> > Following is one of the messages and same messages with 
> > different values are poping up regularly.
> > ---
> > Kernel unaligned access to 0xe00000007f3d80dc ip=0xa0000002000373b1
> > ---
> 
> We have this message too on our main database server; the 
> interesting part
> is, that the application, which triggers this error, is a 
> database (MaxDB)
> and the process name is "kernel"... Just to avoid confusion: 
> look if there's
> an application with such name running on your system.
> 
> 
> Greetz,
> 
> 
> SIEGENIA-AUBI KG
> Informationswesen
>  
> i.A.
>  
> Markus Döhr
> SAP-CC/BC, SAPDB-DBA
> 
> Tel.:	 +49 6503 917-152
> Fax:	 +49 6503 917-7152
> E-Mail: markus.doehr@siegenia-aubi.com
> Internet: http://www.siegenia-aubi.com 
>   
> 
-
To unsubscribe from this list: send the line "unsubscribe linux-scsi" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

RE: Help: strange messages from kernel on IA64 platform

[Ju, Seokmann]

Hi,

Tuesday, May 16, 2006 5:20 PM, "Döhr, Markus ICC-H" wrote:
> We have this message too on our main database server; the 
> interesting part
> is, that the application, which triggers this error, is a 
> database (MaxDB)
> and the process name is "kernel"... Just to avoid confusion: 
> look if there's
> an application with such name running on your system.
I quickly looked at the system with 'ps' command.
It seems there is no such process which starting its name with "kernel.." on the system.
Thank you for your comment.

Regards,

> -----Original Message-----
> From: "Döhr, Markus ICC-H" [mailto:Markus.Doehr@siegenia-aubi.com] 
> Sent: Tuesday, May 16, 2006 5:20 PM
> To: Ju, Seokmann; Linux Kernel Mailing List
> Cc: linux-scsi@vger.kernel.org
> Subject: RE: Help: strange messages from kernel on IA64 platform
> 
> > During communication in between application and megaraid 
> > driver via IOCTL, the system displays messages which are not 
> > easy to track down.
> > Following is one of the messages and same messages with 
> > different values are poping up regularly.
> > ---
> > Kernel unaligned access to 0xe00000007f3d80dc ip=0xa0000002000373b1
> > ---
> 
> We have this message too on our main database server; the 
> interesting part
> is, that the application, which triggers this error, is a 
> database (MaxDB)
> and the process name is "kernel"... Just to avoid confusion: 
> look if there's
> an application with such name running on your system.
> 
> 
> Greetz,
> 
> 
> SIEGENIA-AUBI KG
> Informationswesen
>  
> i.A.
>  
> Markus Döhr
> SAP-CC/BC, SAPDB-DBA
> 
> Tel.:	 +49 6503 917-152
> Fax:	 +49 6503 917-7152
> E-Mail: markus.doehr@siegenia-aubi.com
> Internet: http://www.siegenia-aubi.com 
>   
> 

RE: Help: strange messages from kernel on IA64 platform

[Chen, Kenneth W]

Ju, Seokmann wrote on Tuesday, May 16, 2006 2:13 PM
> Tuesday, May 16, 2006 5:00 PM, Chase Venters wrote:
> > It's a trap, which means the CPU is effectively calling that 
> function.
> O.K, that's why...
> Then, Is there anyway to look up trap table that the CPU has?

By looking at the instruction address that triggered the unaligned
fault, it is coming from a kernel module.

You should look at the runtime symbol table /proc/kallsyms and try
to map that ip into a function.

- Ken

RE: Help: strange messages from kernel on IA64 platform

[Chen, Kenneth W]

Ju, Seokmann wrote on Tuesday, May 16, 2006 2:13 PM
> Tuesday, May 16, 2006 5:00 PM, Chase Venters wrote:
> > It's a trap, which means the CPU is effectively calling that 
> function.
> O.K, that's why...
> Then, Is there anyway to look up trap table that the CPU has?

By looking at the instruction address that triggered the unaligned
fault, it is coming from a kernel module.

You should look at the runtime symbol table /proc/kallsyms and try
to map that ip into a function.

- Ken

RE: Help: strange messages from kernel on IA64 platform

[Chen, Kenneth W]

Döhr, Markus ICC-H wrote on Tuesday, May 16, 2006 2:20 PM
> > During communication in between application and megaraid 
> > driver via IOCTL, the system displays messages which are not 
> > easy to track down.
> > Following is one of the messages and same messages with 
> > different values are poping up regularly.
> > ---
> > Kernel unaligned access to 0xe00000007f3d80dc ip=0xa0000002000373b1
> > ---
> 
> We have this message too on our main database server; the interesting part
> is, that the application, which triggers this error, is a database (MaxDB)
> and the process name is "kernel"... Just to avoid confusion: look if there's
> an application with such name running on your system.

Unaligned access warning for user space process will print in a slightly
different format.  It will print process name and its pid, something like:

cgc(15270): unaligned access to 0x20000000002b8025, ip=0x4000000000000b21

(you can also make the differentiation by looking at the data and instruction
 address).

- Ken
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To unsubscribe from this list: send the line "unsubscribe linux-scsi" in
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RE: Help: strange messages from kernel on IA64 platform

[Chen, Kenneth W]

Döhr, Markus ICC-H wrote on Tuesday, May 16, 2006 2:20 PM
> > During communication in between application and megaraid 
> > driver via IOCTL, the system displays messages which are not 
> > easy to track down.
> > Following is one of the messages and same messages with 
> > different values are poping up regularly.
> > ---
> > Kernel unaligned access to 0xe00000007f3d80dc ip=0xa0000002000373b1
> > ---
> 
> We have this message too on our main database server; the interesting part
> is, that the application, which triggers this error, is a database (MaxDB)
> and the process name is "kernel"... Just to avoid confusion: look if there's
> an application with such name running on your system.

Unaligned access warning for user space process will print in a slightly
different format.  It will print process name and its pid, something like:

cgc(15270): unaligned access to 0x20000000002b8025, ip=0x4000000000000b21

(you can also make the differentiation by looking at the data and instruction
 address).

- Ken

RE: Help: strange messages from kernel on IA64 platform

[Peter Chubb]

>>>>> "Kenneth" == Kenneth W Chen <Chen> writes:

Kenneth> Ju, Seokmann wrote on Tuesday, May 16, 2006 2:13 PM
>> Tuesday, May 16, 2006 5:00 PM, Chase Venters wrote: > It's a trap,
>> which means the CPU is effectively calling that function.  O.K,
>> that's why...  Then, Is there anyway to look up trap table that the
>> CPU has?

Kenneth> By looking at the instruction address that triggered the
Kenneth> unaligned fault, it is coming from a kernel module.

General details for tracking down unaligned access problems in IA64
linux at http://www.gelato.unsw.edu.au/IA64wiki/UnalignedAccesses
-- 
Dr Peter Chubb  http://www.gelato.unsw.edu.au  peterc AT gelato.unsw.edu.au
http://www.ertos.nicta.com.au           ERTOS within National ICT Australia

RE: Help: strange messages from kernel on IA64 platform

[Peter Chubb]

>>>>> "Kenneth" == Kenneth W Chen <Chen> writes:

Kenneth> Ju, Seokmann wrote on Tuesday, May 16, 2006 2:13 PM
>> Tuesday, May 16, 2006 5:00 PM, Chase Venters wrote: > It's a trap,
>> which means the CPU is effectively calling that function.  O.K,
>> that's why...  Then, Is there anyway to look up trap table that the
>> CPU has?

Kenneth> By looking at the instruction address that triggered the
Kenneth> unaligned fault, it is coming from a kernel module.

General details for tracking down unaligned access problems in IA64
linux at http://www.gelato.unsw.edu.au/IA64wiki/UnalignedAccesses
-- 
Dr Peter Chubb  http://www.gelato.unsw.edu.au  peterc AT gelato.unsw.edu.au
http://www.ertos.nicta.com.au           ERTOS within National ICT Australia

Re: Help: strange messages from kernel on IA64 platform

[Sakurai Hiroomi]

Hi,

I saw same message.

When GAM(Global Array Manager) is started, The following message output.
kernel: kernel unaligned access to 0xe0000001fe1080d4, ip=0xa000000200053371

The uioc structure used by ioctl is defined by packed,
the allignment of each member are disturbed.
In a 64 bit structure, the allignment of member doesn't fit 64 bit
boundary. this causes this messages.
In a 32 bit structure, we don't see the message because the allinment
of member fit 32 bit boundary even if packed is specified. 

patch
I Add 32 bit dummy member to fit 64 bit boundary. I tested.
We confirmed this patch fix the problem by IA64 server.

******************************************************************************
--- linux-2.6.9/drivers/scsi/megaraid/megaraid_ioctl.h.orig	2006-04-03 17:13:03.000000000 +0900
+++ linux-2.6.9/drivers/scsi/megaraid/megaraid_ioctl.h	2006-04-03 17:14:09.000000000 +0900
@@ -132,6 +132,10 @@
 /* Driver Data: */
         void __user *           user_data;
         uint32_t                user_data_len;
+
+        /* 64bit alignment */
+        uint32_t                pad_0xBC;
+
         mraid_passthru_t        __user *user_pthru;
 
         mraid_passthru_t        *pthru32;
******************************************************************************

I'm not participated in the linux-scsi mailing list.
Please reply to the following addresses. 

    E-Mail : sakurai_hiro@soft.fujitsu.com


Best regards,
Hiroomi Sakurai

RE: Help: strange messages from kernel on IA64 platform

[Ju, Seokmann]

On Wednesday, July 12, 2006 4:20 AM, Sakurai Hiroomi wrote:
> When GAM(Global Array Manager) is started, The following 
> message output.
> kernel: kernel unaligned access to 0xe0000001fe1080d4, 
> ip=0xa000000200053371
This is a patch required to address  the issue.
Thank you for the patch.

Seokmann

> -----Original Message-----
> From: linux-scsi-owner@vger.kernel.org 
> [mailto:linux-scsi-owner@vger.kernel.org] On Behalf Of Sakurai Hiroomi
> Sent: Wednesday, July 12, 2006 4:20 AM
> To: linux-scsi@vger.kernel.org; linux-kernel@vger.kernel.org
> Subject: Re: Help: strange messages from kernel on IA64 platform
> 
> Hi,
> 
> I saw same message.
> 
> When GAM(Global Array Manager) is started, The following 
> message output.
> kernel: kernel unaligned access to 0xe0000001fe1080d4, 
> ip=0xa000000200053371
> 
> The uioc structure used by ioctl is defined by packed,
> the allignment of each member are disturbed.
> In a 64 bit structure, the allignment of member doesn't fit 64 bit
> boundary. this causes this messages.
> In a 32 bit structure, we don't see the message because the allinment
> of member fit 32 bit boundary even if packed is specified. 
> 
> patch
> I Add 32 bit dummy member to fit 64 bit boundary. I tested.
> We confirmed this patch fix the problem by IA64 server.
> 
> **************************************************************
> ****************
> --- linux-2.6.9/drivers/scsi/megaraid/megaraid_ioctl.h.orig	
> 2006-04-03 17:13:03.000000000 +0900
> +++ linux-2.6.9/drivers/scsi/megaraid/megaraid_ioctl.h	
> 2006-04-03 17:14:09.000000000 +0900
> @@ -132,6 +132,10 @@
>  /* Driver Data: */
>          void __user *           user_data;
>          uint32_t                user_data_len;
> +
> +        /* 64bit alignment */
> +        uint32_t                pad_0xBC;
> +
>          mraid_passthru_t        __user *user_pthru;
>  
>          mraid_passthru_t        *pthru32;
> **************************************************************
> ****************
> 
> I'm not participated in the linux-scsi mailing list.
> Please reply to the following addresses. 
> 
>     E-Mail : sakurai_hiro@soft.fujitsu.com
> 
> 
> Best regards,
> Hiroomi Sakurai
> 
> 
> -
> To unsubscribe from this list: send the line "unsubscribe 
> linux-scsi" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
> 

RE: Help: strange messages from kernel on IA64 platform

[Ju, Seokmann]

On Wednesday, July 12, 2006 4:20 AM, Sakurai Hiroomi wrote:
> When GAM(Global Array Manager) is started, The following 
> message output.
> kernel: kernel unaligned access to 0xe0000001fe1080d4, 
> ip=0xa000000200053371
This is a patch required to address  the issue.
Thank you for the patch.

Seokmann

> -----Original Message-----
> From: linux-scsi-owner@vger.kernel.org 
> [mailto:linux-scsi-owner@vger.kernel.org] On Behalf Of Sakurai Hiroomi
> Sent: Wednesday, July 12, 2006 4:20 AM
> To: linux-scsi@vger.kernel.org; linux-kernel@vger.kernel.org
> Subject: Re: Help: strange messages from kernel on IA64 platform
> 
> Hi,
> 
> I saw same message.
> 
> When GAM(Global Array Manager) is started, The following 
> message output.
> kernel: kernel unaligned access to 0xe0000001fe1080d4, 
> ip=0xa000000200053371
> 
> The uioc structure used by ioctl is defined by packed,
> the allignment of each member are disturbed.
> In a 64 bit structure, the allignment of member doesn't fit 64 bit
> boundary. this causes this messages.
> In a 32 bit structure, we don't see the message because the allinment
> of member fit 32 bit boundary even if packed is specified. 
> 
> patch
> I Add 32 bit dummy member to fit 64 bit boundary. I tested.
> We confirmed this patch fix the problem by IA64 server.
> 
> **************************************************************
> ****************
> --- linux-2.6.9/drivers/scsi/megaraid/megaraid_ioctl.h.orig	
> 2006-04-03 17:13:03.000000000 +0900
> +++ linux-2.6.9/drivers/scsi/megaraid/megaraid_ioctl.h	
> 2006-04-03 17:14:09.000000000 +0900
> @@ -132,6 +132,10 @@
>  /* Driver Data: */
>          void __user *           user_data;
>          uint32_t                user_data_len;
> +
> +        /* 64bit alignment */
> +        uint32_t                pad_0xBC;
> +
>          mraid_passthru_t        __user *user_pthru;
>  
>          mraid_passthru_t        *pthru32;
> **************************************************************
> ****************
> 
> I'm not participated in the linux-scsi mailing list.
> Please reply to the following addresses. 
> 
>     E-Mail : sakurai_hiro@soft.fujitsu.com
> 
> 
> Best regards,
> Hiroomi Sakurai
> 
> 
> -
> To unsubscribe from this list: send the line "unsubscribe 
> linux-scsi" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
> 

Re: Help: strange messages from kernel on IA64 platform

[Arjan van de Ven]

On Wed, 2006-07-12 at 17:19 +0900, Sakurai Hiroomi wrote:
> Hi,
> 
> I saw same message.
> 
> When GAM(Global Array Manager) is started, The following message output.
> kernel: kernel unaligned access to 0xe0000001fe1080d4, ip=0xa000000200053371

first of all you should file a bug against this kernel; the kernel
should not printk about unaligned accesses by default!

> 
> The uioc structure used by ioctl is defined by packed,
> the allignment of each member are disturbed.
> In a 64 bit structure, the allignment of member doesn't fit 64 bit
> boundary. this causes this messages.
> In a 32 bit structure, we don't see the message because the allinment
> of member fit 32 bit boundary even if packed is specified. 
> 
> patch
> I Add 32 bit dummy member to fit 64 bit boundary. I tested.
> We confirmed this patch fix the problem by IA64 server.


this changes the calling convention of this structure!
If there is no strict calling convention, then the packed can be
removed, but if there is your patch changes the ABI!!
(and you could then fix it by using get_unaligned() in the places that
use this field)