Re: Linix-3.6.3 sda, sdb drives in reverse order (with a USB 2.0 drives and a monolithic kernel configuration)

2012-10-27 Thread Andi Kleen
On Sun, Oct 28, 2012 at 04:17:00AM +0100, Wallak wrote:
> I've found where this issue come from. This behavior was introduced
> with the commit: 0cc15d03bcccdf95e2bd82e094e6064e61b54207.The
> description is available below. Removing this patch fix the drive
> order.

Hmm the patch should only affect the floppy. I don't see how it could 
affect anything else. Maybe it's just generic timing change
that disrupts your boot sequence (if that's the case something else
could have caused it too)

Maybe Arjan has an idea.

-Andi

> 
> 
> Best Regards,
> Wallak.
> 
> 
> commit 0cc15d03bcccdf95e2bd82e094e6064e61b54207
> Author: Andi Kleen 
> Date:   Mon Jul 2 17:27:04 2012 -0700
> 
> floppy: Run floppy initialization asynchronous
> 
> floppy_init is quite slow, 3s on my test system to determine
> that there is no floppy. Run it asynchronous to the other
> init calls to improve boot time.
> 
> [jkos...@suse.cz: fix modular build]
> 
> Signed-off-by: Andi Kleen 
> Signed-off-by: Jiri Kosina 
> 
> 
> 
> 
> Wallak wrote:
> >Chris Friesen wrote:
> >>On 10/26/2012 01:43 PM, Wallak wrote:
> >>>Chris Friesen wrote:
> On 10/25/2012 04:49 PM, Wallak wrote:
> >I've a very annoying behavior with the linux-3.6.x kernels
> >release, and
> >a monolithic configuration. The USB 2.0 drives are mapped first with
> >/dev/sda, /dev/sdb... devices, and than the SATA AHCI
> >drives come after.
> >This is out of order with the BIOS configuration and breaks a program
> >like lilo. This is also annoying when we use a static
> >partition mapping.
> >
> >Linux-3.5 works fine. Where this bug come from ? Is this a
> >patch to get
> >the old, and classical behavior ?
> 
> As you have discovered it's fragile to rely on /dev/sd* names since a
> BIOS update, kernel update, or motherboard replacement could
> conceivably cause them to change.
> 
> Better to use something like partition labels that you control and
> that don't change.
> 
> Chris
> 
> >>>You are right, when we have a configuration with a lot of drvies and
> >>>adapters SATA, old SCSI,.. etc. the order may change. But having the
> >>>main SATA hard drive defined, as the BIOS boot device, behind external
> >>>and removable USB drives is in my opinion a bug.And may lead
> >>>to security
> >>>issues (drives with the same label, etc...).
> >>>
> >>>Using =LABEL, or =UUID with a bootloader like grub or lilo,
> >>>save the the
> >>>boot device mapped drive partition number , and so booting on an older
> >>>kernel like linux 3.5 will fail. If we remove the external USB drive,
> >>>the boot process will fail too...
> >>>
> >>>So such a bug have to be fix.
> >>
> >>If you specify "root=LABEL=" as part of the kernel boot
> >>args in grub does it not check the label at boot time?
> >
> >Using root=LABEL= or root=UUID= don't work on a plain kernel, this
> >feature may be handled by an initrd trick. Otherwise for all non
> >root partitions UUID= work fine.
> >Nevertheless not fixing this bug yields some other issues:  Using
> >lilo to launch a second OS (other= option) fail, the command try
> >to parse partitions available on /dev/sda, and miss the real main
> >HDD. Boot drive must be force with lilo options...
> >SATA drives have, most of the time, no reason to be behind USB
> >drives. If we want to get a reliable behavior: /dev/sda must be
> >mapped to the BIOS boot device. Using the same behavior as
> >linux-3.5 will be fine.
> >
> >Wallak.
> >
> >>
> >>Chris
> >>
> >
> 

-- 
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Re: Linix-3.6.3 sda, sdb drives in reverse order (with a USB 2.0 drives and a monolithic kernel configuration)

2012-10-27 Thread Wallak
I've found where this issue come from. This behavior was introduced with 
the commit: 0cc15d03bcccdf95e2bd82e094e6064e61b54207.The description is 
available below. Removing this patch fix the drive order.



Best Regards,
Wallak.


commit 0cc15d03bcccdf95e2bd82e094e6064e61b54207
Author: Andi Kleen 
Date:   Mon Jul 2 17:27:04 2012 -0700

floppy: Run floppy initialization asynchronous

floppy_init is quite slow, 3s on my test system to determine
that there is no floppy. Run it asynchronous to the other
init calls to improve boot time.

[jkos...@suse.cz: fix modular build]

Signed-off-by: Andi Kleen 
Signed-off-by: Jiri Kosina 




Wallak wrote:

Chris Friesen wrote:

On 10/26/2012 01:43 PM, Wallak wrote:

Chris Friesen wrote:

On 10/25/2012 04:49 PM, Wallak wrote:
I've a very annoying behavior with the linux-3.6.x kernels 
release, and

a monolithic configuration. The USB 2.0 drives are mapped first with
/dev/sda, /dev/sdb... devices, and than the SATA AHCI drives come 
after.

This is out of order with the BIOS configuration and breaks a program
like lilo. This is also annoying when we use a static partition 
mapping.


Linux-3.5 works fine. Where this bug come from ? Is this a patch 
to get

the old, and classical behavior ?


As you have discovered it's fragile to rely on /dev/sd* names since a
BIOS update, kernel update, or motherboard replacement could
conceivably cause them to change.

Better to use something like partition labels that you control and
that don't change.

Chris


You are right, when we have a configuration with a lot of drvies and
adapters SATA, old SCSI,.. etc. the order may change. But having the
main SATA hard drive defined, as the BIOS boot device, behind external
and removable USB drives is in my opinion a bug.And may lead to 
security

issues (drives with the same label, etc...).

Using =LABEL, or =UUID with a bootloader like grub or lilo, save the 
the

boot device mapped drive partition number , and so booting on an older
kernel like linux 3.5 will fail. If we remove the external USB drive,
the boot process will fail too...

So such a bug have to be fix.


If you specify "root=LABEL=" as part of the kernel boot args 
in grub does it not check the label at boot time?


Using root=LABEL= or root=UUID= don't work on a plain kernel, this 
feature may be handled by an initrd trick. Otherwise for all non root 
partitions UUID= work fine.
Nevertheless not fixing this bug yields some other issues:  Using lilo 
to launch a second OS (other= option) fail, the command try to parse 
partitions available on /dev/sda, and miss the real main HDD. Boot 
drive must be force with lilo options...
SATA drives have, most of the time, no reason to be behind USB drives. 
If we want to get a reliable behavior: /dev/sda must be mapped to the 
BIOS boot device. Using the same behavior as linux-3.5 will be fine.


Wallak.



Chris





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Re: Linix-3.6.3 sda, sdb drives in reverse order (with a USB 2.0 drives and a monolithic kernel configuration)

2012-10-27 Thread Wallak
I've found where this issue come from. This behavior was introduced with 
the commit: 0cc15d03bcccdf95e2bd82e094e6064e61b54207.The description is 
available below. Removing this patch fix the drive order.



Best Regards,
Wallak.


commit 0cc15d03bcccdf95e2bd82e094e6064e61b54207
Author: Andi Kleen a...@linux.intel.com
Date:   Mon Jul 2 17:27:04 2012 -0700

floppy: Run floppy initialization asynchronous

floppy_init is quite slow, 3s on my test system to determine
that there is no floppy. Run it asynchronous to the other
init calls to improve boot time.

[jkos...@suse.cz: fix modular build]

Signed-off-by: Andi Kleen a...@linux.intel.com
Signed-off-by: Jiri Kosina jkos...@suse.cz




Wallak wrote:

Chris Friesen wrote:

On 10/26/2012 01:43 PM, Wallak wrote:

Chris Friesen wrote:

On 10/25/2012 04:49 PM, Wallak wrote:
I've a very annoying behavior with the linux-3.6.x kernels 
release, and

a monolithic configuration. The USB 2.0 drives are mapped first with
/dev/sda, /dev/sdb... devices, and than the SATA AHCI drives come 
after.

This is out of order with the BIOS configuration and breaks a program
like lilo. This is also annoying when we use a static partition 
mapping.


Linux-3.5 works fine. Where this bug come from ? Is this a patch 
to get

the old, and classical behavior ?


As you have discovered it's fragile to rely on /dev/sd* names since a
BIOS update, kernel update, or motherboard replacement could
conceivably cause them to change.

Better to use something like partition labels that you control and
that don't change.

Chris


You are right, when we have a configuration with a lot of drvies and
adapters SATA, old SCSI,.. etc. the order may change. But having the
main SATA hard drive defined, as the BIOS boot device, behind external
and removable USB drives is in my opinion a bug.And may lead to 
security

issues (drives with the same label, etc...).

Using =LABEL, or =UUID with a bootloader like grub or lilo, save the 
the

boot device mapped drive partition number , and so booting on an older
kernel like linux 3.5 will fail. If we remove the external USB drive,
the boot process will fail too...

So such a bug have to be fix.


If you specify root=LABEL=label as part of the kernel boot args 
in grub does it not check the label at boot time?


Using root=LABEL= or root=UUID= don't work on a plain kernel, this 
feature may be handled by an initrd trick. Otherwise for all non root 
partitions UUID= work fine.
Nevertheless not fixing this bug yields some other issues:  Using lilo 
to launch a second OS (other= option) fail, the command try to parse 
partitions available on /dev/sda, and miss the real main HDD. Boot 
drive must be force with lilo options...
SATA drives have, most of the time, no reason to be behind USB drives. 
If we want to get a reliable behavior: /dev/sda must be mapped to the 
BIOS boot device. Using the same behavior as linux-3.5 will be fine.


Wallak.



Chris





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Re: Linix-3.6.3 sda, sdb drives in reverse order (with a USB 2.0 drives and a monolithic kernel configuration)

2012-10-27 Thread Andi Kleen
On Sun, Oct 28, 2012 at 04:17:00AM +0100, Wallak wrote:
 I've found where this issue come from. This behavior was introduced
 with the commit: 0cc15d03bcccdf95e2bd82e094e6064e61b54207.The
 description is available below. Removing this patch fix the drive
 order.

Hmm the patch should only affect the floppy. I don't see how it could 
affect anything else. Maybe it's just generic timing change
that disrupts your boot sequence (if that's the case something else
could have caused it too)

Maybe Arjan has an idea.

-Andi

 
 
 Best Regards,
 Wallak.
 
 
 commit 0cc15d03bcccdf95e2bd82e094e6064e61b54207
 Author: Andi Kleen a...@linux.intel.com
 Date:   Mon Jul 2 17:27:04 2012 -0700
 
 floppy: Run floppy initialization asynchronous
 
 floppy_init is quite slow, 3s on my test system to determine
 that there is no floppy. Run it asynchronous to the other
 init calls to improve boot time.
 
 [jkos...@suse.cz: fix modular build]
 
 Signed-off-by: Andi Kleen a...@linux.intel.com
 Signed-off-by: Jiri Kosina jkos...@suse.cz
 
 
 
 
 Wallak wrote:
 Chris Friesen wrote:
 On 10/26/2012 01:43 PM, Wallak wrote:
 Chris Friesen wrote:
 On 10/25/2012 04:49 PM, Wallak wrote:
 I've a very annoying behavior with the linux-3.6.x kernels
 release, and
 a monolithic configuration. The USB 2.0 drives are mapped first with
 /dev/sda, /dev/sdb... devices, and than the SATA AHCI
 drives come after.
 This is out of order with the BIOS configuration and breaks a program
 like lilo. This is also annoying when we use a static
 partition mapping.
 
 Linux-3.5 works fine. Where this bug come from ? Is this a
 patch to get
 the old, and classical behavior ?
 
 As you have discovered it's fragile to rely on /dev/sd* names since a
 BIOS update, kernel update, or motherboard replacement could
 conceivably cause them to change.
 
 Better to use something like partition labels that you control and
 that don't change.
 
 Chris
 
 You are right, when we have a configuration with a lot of drvies and
 adapters SATA, old SCSI,.. etc. the order may change. But having the
 main SATA hard drive defined, as the BIOS boot device, behind external
 and removable USB drives is in my opinion a bug.And may lead
 to security
 issues (drives with the same label, etc...).
 
 Using =LABEL, or =UUID with a bootloader like grub or lilo,
 save the the
 boot device mapped drive partition number , and so booting on an older
 kernel like linux 3.5 will fail. If we remove the external USB drive,
 the boot process will fail too...
 
 So such a bug have to be fix.
 
 If you specify root=LABEL=label as part of the kernel boot
 args in grub does it not check the label at boot time?
 
 Using root=LABEL= or root=UUID= don't work on a plain kernel, this
 feature may be handled by an initrd trick. Otherwise for all non
 root partitions UUID= work fine.
 Nevertheless not fixing this bug yields some other issues:  Using
 lilo to launch a second OS (other= option) fail, the command try
 to parse partitions available on /dev/sda, and miss the real main
 HDD. Boot drive must be force with lilo options...
 SATA drives have, most of the time, no reason to be behind USB
 drives. If we want to get a reliable behavior: /dev/sda must be
 mapped to the BIOS boot device. Using the same behavior as
 linux-3.5 will be fine.
 
 Wallak.
 
 
 Chris
 
 
 

-- 
a...@linux.intel.com -- Speaking for myself only
--
To unsubscribe from this list: send the line unsubscribe linux-kernel in
the body of a message to majord...@vger.kernel.org
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Please read the FAQ at  http://www.tux.org/lkml/


Re: Linix-3.6.3 sda, sdb drives in reverse order (with a USB 2.0 drives and a monolithic kernel configuration)

2012-10-26 Thread Wallak

Chris Friesen wrote:

On 10/26/2012 01:43 PM, Wallak wrote:

Chris Friesen wrote:

On 10/25/2012 04:49 PM, Wallak wrote:
I've a very annoying behavior with the linux-3.6.x kernels release, 
and

a monolithic configuration. The USB 2.0 drives are mapped first with
/dev/sda, /dev/sdb... devices, and than the SATA AHCI drives come 
after.

This is out of order with the BIOS configuration and breaks a program
like lilo. This is also annoying when we use a static partition 
mapping.


Linux-3.5 works fine. Where this bug come from ? Is this a patch to 
get

the old, and classical behavior ?


As you have discovered it's fragile to rely on /dev/sd* names since a
BIOS update, kernel update, or motherboard replacement could
conceivably cause them to change.

Better to use something like partition labels that you control and
that don't change.

Chris


You are right, when we have a configuration with a lot of drvies and
adapters SATA, old SCSI,.. etc. the order may change. But having the
main SATA hard drive defined, as the BIOS boot device, behind external
and removable USB drives is in my opinion a bug.And may lead to security
issues (drives with the same label, etc...).

Using =LABEL, or =UUID with a bootloader like grub or lilo, save the the
boot device mapped drive partition number , and so booting on an older
kernel like linux 3.5 will fail. If we remove the external USB drive,
the boot process will fail too...

So such a bug have to be fix.


If you specify "root=LABEL=" as part of the kernel boot args in 
grub does it not check the label at boot time?


Using root=LABEL= or root=UUID= don't work on a plain kernel, this 
feature may be handled by an initrd trick. Otherwise for all non root 
partitions UUID= work fine.
Nevertheless not fixing this bug yields some other issues:  Using lilo 
to launch a second OS (other= option) fail, the command try to parse 
partitions available on /dev/sda, and miss the real main HDD. Boot drive 
must be force with lilo options...
SATA drives have, most of the time, no reason to be behind USB drives. 
If we want to get a reliable behavior: /dev/sda must be mapped to the 
BIOS boot device. Using the same behavior as linux-3.5 will be fine.


Wallak.



Chris



--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/


Re: Linix-3.6.3 sda, sdb drives in reverse order (with a USB 2.0 drives and a monolithic kernel configuration)

2012-10-26 Thread Chris Friesen

On 10/26/2012 01:43 PM, Wallak wrote:

Chris Friesen wrote:

On 10/25/2012 04:49 PM, Wallak wrote:

I've a very annoying behavior with the linux-3.6.x kernels release, and
a monolithic configuration. The USB 2.0 drives are mapped first with
/dev/sda, /dev/sdb... devices, and than the SATA AHCI drives come after.
This is out of order with the BIOS configuration and breaks a program
like lilo. This is also annoying when we use a static partition mapping.

Linux-3.5 works fine. Where this bug come from ? Is this a patch to get
the old, and classical behavior ?


As you have discovered it's fragile to rely on /dev/sd* names since a
BIOS update, kernel update, or motherboard replacement could
conceivably cause them to change.

Better to use something like partition labels that you control and
that don't change.

Chris


You are right, when we have a configuration with a lot of drvies and
adapters SATA, old SCSI,.. etc. the order may change. But having the
main SATA hard drive defined, as the BIOS boot device, behind external
and removable USB drives is in my opinion a bug.And may lead to security
issues (drives with the same label, etc...).

Using =LABEL, or =UUID with a bootloader like grub or lilo, save the the
boot device mapped drive partition number , and so booting on an older
kernel like linux 3.5 will fail. If we remove the external USB drive,
the boot process will fail too...

So such a bug have to be fix.


If you specify "root=LABEL=" as part of the kernel boot args in 
grub does it not check the label at boot time?


Chris
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
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Re: Linix-3.6.3 sda, sdb drives in reverse order (with a USB 2.0 drives and a monolithic kernel configuration)

2012-10-26 Thread Wallak

Chris Friesen wrote:

On 10/25/2012 04:49 PM, Wallak wrote:

I've a very annoying behavior with the linux-3.6.x kernels release, and
a monolithic configuration. The USB 2.0 drives are mapped first with
/dev/sda, /dev/sdb... devices, and than the SATA AHCI drives come after.
This is out of order with the BIOS configuration and breaks a program
like lilo. This is also annoying when we use a static partition mapping.

Linux-3.5 works fine. Where this bug come from ? Is this a patch to get
the old, and classical behavior ?


As you have discovered it's fragile to rely on /dev/sd* names since a 
BIOS update, kernel update, or motherboard replacement could 
conceivably cause them to change.


Better to use something like partition labels that you control and 
that don't change.


Chris

  You are right, when we have a configuration with a lot of drvies and 
adapters SATA, old SCSI,.. etc. the order may change. But having the 
main SATA hard drive defined, as the BIOS boot device, behind external 
and removable USB drives is in my opinion a bug.And may lead to security 
issues (drives with the same label, etc...).


 Using =LABEL, or =UUID with a bootloader like grub or lilo, save the 
the boot device mapped drive partition number , and so booting on an 
older kernel like linux 3.5 will fail. If we remove the external USB 
drive, the boot process will fail too...


So such a bug have to be fix.


Wallak.

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/


Re: Linix-3.6.3 sda, sdb drives in reverse order (with a USB 2.0 drives and a monolithic kernel configuration)

2012-10-26 Thread Wallak

Chris Friesen wrote:

On 10/25/2012 04:49 PM, Wallak wrote:

I've a very annoying behavior with the linux-3.6.x kernels release, and
a monolithic configuration. The USB 2.0 drives are mapped first with
/dev/sda, /dev/sdb... devices, and than the SATA AHCI drives come after.
This is out of order with the BIOS configuration and breaks a program
like lilo. This is also annoying when we use a static partition mapping.

Linux-3.5 works fine. Where this bug come from ? Is this a patch to get
the old, and classical behavior ?


As you have discovered it's fragile to rely on /dev/sd* names since a 
BIOS update, kernel update, or motherboard replacement could 
conceivably cause them to change.


Better to use something like partition labels that you control and 
that don't change.


Chris

  You are right, when we have a configuration with a lot of drvies and 
adapters SATA, old SCSI,.. etc. the order may change. But having the 
main SATA hard drive defined, as the BIOS boot device, behind external 
and removable USB drives is in my opinion a bug.And may lead to security 
issues (drives with the same label, etc...).


 Using =LABEL, or =UUID with a bootloader like grub or lilo, save the 
the boot device mapped drive partition number , and so booting on an 
older kernel like linux 3.5 will fail. If we remove the external USB 
drive, the boot process will fail too...


So such a bug have to be fix.


Wallak.

--
To unsubscribe from this list: send the line unsubscribe linux-kernel in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/


Re: Linix-3.6.3 sda, sdb drives in reverse order (with a USB 2.0 drives and a monolithic kernel configuration)

2012-10-26 Thread Chris Friesen

On 10/26/2012 01:43 PM, Wallak wrote:

Chris Friesen wrote:

On 10/25/2012 04:49 PM, Wallak wrote:

I've a very annoying behavior with the linux-3.6.x kernels release, and
a monolithic configuration. The USB 2.0 drives are mapped first with
/dev/sda, /dev/sdb... devices, and than the SATA AHCI drives come after.
This is out of order with the BIOS configuration and breaks a program
like lilo. This is also annoying when we use a static partition mapping.

Linux-3.5 works fine. Where this bug come from ? Is this a patch to get
the old, and classical behavior ?


As you have discovered it's fragile to rely on /dev/sd* names since a
BIOS update, kernel update, or motherboard replacement could
conceivably cause them to change.

Better to use something like partition labels that you control and
that don't change.

Chris


You are right, when we have a configuration with a lot of drvies and
adapters SATA, old SCSI,.. etc. the order may change. But having the
main SATA hard drive defined, as the BIOS boot device, behind external
and removable USB drives is in my opinion a bug.And may lead to security
issues (drives with the same label, etc...).

Using =LABEL, or =UUID with a bootloader like grub or lilo, save the the
boot device mapped drive partition number , and so booting on an older
kernel like linux 3.5 will fail. If we remove the external USB drive,
the boot process will fail too...

So such a bug have to be fix.


If you specify root=LABEL=label as part of the kernel boot args in 
grub does it not check the label at boot time?


Chris
--
To unsubscribe from this list: send the line unsubscribe linux-kernel in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/


Re: Linix-3.6.3 sda, sdb drives in reverse order (with a USB 2.0 drives and a monolithic kernel configuration)

2012-10-26 Thread Wallak

Chris Friesen wrote:

On 10/26/2012 01:43 PM, Wallak wrote:

Chris Friesen wrote:

On 10/25/2012 04:49 PM, Wallak wrote:
I've a very annoying behavior with the linux-3.6.x kernels release, 
and

a monolithic configuration. The USB 2.0 drives are mapped first with
/dev/sda, /dev/sdb... devices, and than the SATA AHCI drives come 
after.

This is out of order with the BIOS configuration and breaks a program
like lilo. This is also annoying when we use a static partition 
mapping.


Linux-3.5 works fine. Where this bug come from ? Is this a patch to 
get

the old, and classical behavior ?


As you have discovered it's fragile to rely on /dev/sd* names since a
BIOS update, kernel update, or motherboard replacement could
conceivably cause them to change.

Better to use something like partition labels that you control and
that don't change.

Chris


You are right, when we have a configuration with a lot of drvies and
adapters SATA, old SCSI,.. etc. the order may change. But having the
main SATA hard drive defined, as the BIOS boot device, behind external
and removable USB drives is in my opinion a bug.And may lead to security
issues (drives with the same label, etc...).

Using =LABEL, or =UUID with a bootloader like grub or lilo, save the the
boot device mapped drive partition number , and so booting on an older
kernel like linux 3.5 will fail. If we remove the external USB drive,
the boot process will fail too...

So such a bug have to be fix.


If you specify root=LABEL=label as part of the kernel boot args in 
grub does it not check the label at boot time?


Using root=LABEL= or root=UUID= don't work on a plain kernel, this 
feature may be handled by an initrd trick. Otherwise for all non root 
partitions UUID= work fine.
Nevertheless not fixing this bug yields some other issues:  Using lilo 
to launch a second OS (other= option) fail, the command try to parse 
partitions available on /dev/sda, and miss the real main HDD. Boot drive 
must be force with lilo options...
SATA drives have, most of the time, no reason to be behind USB drives. 
If we want to get a reliable behavior: /dev/sda must be mapped to the 
BIOS boot device. Using the same behavior as linux-3.5 will be fine.


Wallak.



Chris



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Re: Linix-3.6.3 sda, sdb drives in reverse order (with a USB 2.0 drives and a monolithic kernel configuration)

2012-10-25 Thread Chris Friesen

On 10/25/2012 04:49 PM, Wallak wrote:

I've a very annoying behavior with the linux-3.6.x kernels release, and
a monolithic configuration. The USB 2.0 drives are mapped first with
/dev/sda, /dev/sdb... devices, and than the SATA AHCI drives come after.
This is out of order with the BIOS configuration and breaks a program
like lilo. This is also annoying when we use a static partition mapping.

Linux-3.5 works fine. Where this bug come from ? Is this a patch to get
the old, and classical behavior ?


As you have discovered it's fragile to rely on /dev/sd* names since a 
BIOS update, kernel update, or motherboard replacement could conceivably 
cause them to change.


Better to use something like partition labels that you control and that 
don't change.


Chris
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Re: Linix-3.6.3 sda, sdb drives in reverse order (with a USB 2.0 drives and a monolithic kernel configuration)

2012-10-25 Thread Chris Friesen

On 10/25/2012 04:49 PM, Wallak wrote:

I've a very annoying behavior with the linux-3.6.x kernels release, and
a monolithic configuration. The USB 2.0 drives are mapped first with
/dev/sda, /dev/sdb... devices, and than the SATA AHCI drives come after.
This is out of order with the BIOS configuration and breaks a program
like lilo. This is also annoying when we use a static partition mapping.

Linux-3.5 works fine. Where this bug come from ? Is this a patch to get
the old, and classical behavior ?


As you have discovered it's fragile to rely on /dev/sd* names since a 
BIOS update, kernel update, or motherboard replacement could conceivably 
cause them to change.


Better to use something like partition labels that you control and that 
don't change.


Chris
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To unsubscribe from this list: send the line unsubscribe linux-kernel in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/