64 bit kernel won't mount /

64 bit kernel won't mount /

[Gene Heskett]

Greetings;

Amd Phenom, 8Gb of dram on an Asus M2N-SLI Deluxe board.  So old USB3 
isn't.

Ubuntu 10.04.4 LTS 32 bit server install here.  A recent experiment with a 
32 bit Wheezy (2.7) worked extremely well when I enabled it to install an 
amd64 kernel, fastest and smoothest this machine has ever worked.  
Unfortunately I destroyed it by installing a library firefox was 
complaining about the lack thereof, it pulled in about 20 other packages 
and destroyed what little KDE I had installed to be able to use kmail.

I have been reading up on man fstab, but it has not solved my problem of 
the boot waiting, sometimes for 30 seconds, for the drive to be mounted at 
/ to appear.  There is no disk activity during this wait period, and it 
does not always do it when booting a 32 bit PAE kernel.

But if I build an amd64 version of that kernel, it stops dead, no disk 
activity after announcing that the / device has not yet checked in.

But, after waiting a minute, I hit m to get what is marked as a root 
terminal, but which has no rights, I see that the directory contents of / 
are visible.

Fdisk complains that there are 3503 unallocated 512 byte sectors after 
partition 1 on the disk, but its been doing that for 3 or 4 years.  
Terrabyte disk so its not seriously effected unless it slows it somehow 
that I haven't noticed.

On wheezy, for as long as it worked, it worked a treat.

Suggested fix for the 64 bit boot stall? I am familiar with make xconfig.

Thanks all.

Cheers, Gene Heskett
-- 
"There are four boxes to be used in defense of liberty:
 soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
Genes Web page <http://geneslinuxbox.net:6309/gene>
US V Castleman, SCOTUS, Mar 2014 is grounds for Impeaching SCOTUS

Re: 64 bit kernel won't mount /

[Gene Heskett]

On Monday 19 January 2015 11:45:41 Gene Heskett did opine
And Gene did reply:
> Greetings;
> 
> Amd Phenom, 8Gb of dram on an Asus M2N-SLI Deluxe board.  So old USB3
> isn't.
> 
> Ubuntu 10.04.4 LTS 32 bit server install here.  A recent experiment
> with a 32 bit Wheezy (2.7) worked extremely well when I enabled it to
> install an amd64 kernel, fastest and smoothest this machine has ever
> worked. Unfortunately I destroyed it by installing a library firefox
> was complaining about the lack thereof, it pulled in about 20 other
> packages and destroyed what little KDE I had installed to be able to
> use kmail.
> 
> I have been reading up on man fstab, but it has not solved my problem
> of the boot waiting, sometimes for 30 seconds, for the drive to be
> mounted at / to appear.  There is no disk activity during this wait
> period, and it does not always do it when booting a 32 bit PAE kernel.
> 
> But if I build an amd64 version of that kernel, it stops dead, no disk
> activity after announcing that the / device has not yet checked in.
> 
> But, after waiting a minute, I hit m to get what is marked as a root
> terminal, but which has no rights, I see that the directory contents of
> / are visible.
> 
> Fdisk complains that there are 3503 unallocated 512 byte sectors after
> partition 1 on the disk, but its been doing that for 3 or 4 years.
> Terrabyte disk so its not seriously effected unless it slows it somehow
> that I haven't noticed.
> 
> On wheezy, for as long as it worked, it worked a treat.
> 
> Suggested fix for the 64 bit boot stall? I am familiar with make
> xconfig.
> 
> Thanks all.
> 
> Cheers, Gene Heskett

Ping?

Secondary problem, seems like a miss-match between partitioning tools.

2 of my 4 1Tb drives can do 4096 byte sectors.
fdisk complains noisily about the partitions I have setup on one of these 
disks not being starting sector aligned, yet when I did the partitioning 
with gparted, the align with "cylinders" was checked.

Do we have a partitioning tool that can actually sort this correctly on a 
4k sector disk?

Cheers, Gene Heskett
-- 
"There are four boxes to be used in defense of liberty:
 soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
Genes Web page <http://geneslinuxbox.net:6309/gene>
US V Castleman, SCOTUS, Mar 2014 is grounds for Impeaching SCOTUS

Re: 64 bit kernel won't mount /

[One Thousand Gnomes]

On Mon, 19 Jan 2015 11:45:41 -0500
Gene Heskett <gheskett@wdtv.com> wrote:

> Greetings;
> 
> Amd Phenom, 8Gb of dram on an Asus M2N-SLI Deluxe board.  So old USB3 
> isn't.
> 
> Ubuntu 10.04.4 LTS 32 bit server install here.  A recent experiment with a 

Then you want to ask Ubuntu lists, nobody here can remember that far back
8) or did you mean 14.04 ?

> I have been reading up on man fstab, but it has not solved my problem of 
> the boot waiting, sometimes for 30 seconds, for the drive to be mounted at 
> / to appear.  There is no disk activity during this wait period, and it 
> does not always do it when booting a 32 bit PAE kernel.

30 seconds is about the timeout for the case when there appears to be a
drive but probing it gets no results.

> Fdisk complains that there are 3503 unallocated 512 byte sectors after 
> partition 1 on the disk, but its been doing that for 3 or 4 years.  

Doesn't matter.

Alan

Re: 64 bit kernel won't mount /

[Gene Heskett]

On Wednesday 21 January 2015 12:23:26 One Thousand Gnomes did opine
And Gene did reply:
> On Mon, 19 Jan 2015 11:45:41 -0500
> 
> Gene Heskett <gheskett@wdtv.com> wrote:
> > Greetings;
> > 
> > Amd Phenom, 8Gb of dram on an Asus M2N-SLI Deluxe board.  So old USB3
> > isn't.
> > 
> > Ubuntu 10.04.4 LTS 32 bit server install here.  A recent experiment
> > with a
> 
> Then you want to ask Ubuntu lists, nobody here can remember that far
> back 8) or did you mean 14.04 ?

Nope, stuck on the 10.04.4 release as yet as we haven't managed to 
successfully build an RTAI enabled kernel for wheezy or any of the other 
LTS distros like Mint 17.

We are running computer numerically controlled software, known as LinuxCNC 
on these machines as they demand an IRQ latency of less than 20 
microseconds when you are generating the step and dir pulses with 
software.  Even a 20% wobble in this timing destroys the stay locked 
torque of a stepper motor.

> > I have been reading up on man fstab, but it has not solved my problem
> > of the boot waiting, sometimes for 30 seconds, for the drive to be
> > mounted at / to appear.  There is no disk activity during this wait
> > period, and it does not always do it when booting a 32 bit PAE
> > kernel.
> 
> 30 seconds is about the timeout for the case when there appears to be a
> drive but probing it gets no results.

I've waited 10 minutes or more.  No biscuit.

I am convinced ATM that this boot stall is an artifact of the fact that 
none of the linux installers used, knows a thing about 4k/sector disks, 
and that somehow in my configuring a .config, I have crippled the kernels 
ability to deal with a miss-aligned disk partition, and none of the 
installers is smart enough to align its partitions.  The net results of 
course are 15M/sec write speeds on a disk that can do 120M/sec when it 
does work. But first, it has to boot.
 
> > Fdisk complains that there are 3503 unallocated 512 byte sectors
> > after partition 1 on the disk, but its been doing that for 3 or 4
> > years.
> 
> Doesn't matter.

I didn't think so.  But fdisk still complains about the miss-alignment if 
it exists. This disk is pure 512 byte sectors=no problem.

> Alan

Thanks Alan.

Cheers, Gene Heskett
-- 
"There are four boxes to be used in defense of liberty:
 soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
Genes Web page <http://geneslinuxbox.net:6309/gene>
US V Castleman, SCOTUS, Mar 2014 is grounds for Impeaching SCOTUS

Re: 64 bit kernel won't mount /

[One Thousand Gnomes]

> I am convinced ATM that this boot stall is an artifact of the fact that 
> none of the linux installers used, knows a thing about 4k/sector disks, 
> and that somehow in my configuring a .config, I have crippled the kernels 
> ability to deal with a miss-aligned disk partition, and none of the 
> installers is smart enough to align its partitions.  The net results of 
> course are 15M/sec write speeds on a disk that can do 120M/sec when it 
> does work. But first, it has to boot.

Unlikely. Apart from fdisk the setup is basically invisible. The drive
reports a block size and an offset. The firmware offset is chosen so that
the chassic DOS alignments in fdisk happen to just fall nicely on 4K
boundaries for partition starts.

There is nothing special the OS does to deal with ATA/SATA 4K sectors.

Alan

Re: 64 bit kernel won't mount /

[Gene Heskett]

On Thursday 22 January 2015 10:34:58 One Thousand Gnomes did opine
And Gene did reply:
> > I am convinced ATM that this boot stall is an artifact of the fact
> > that none of the linux installers used, knows a thing about
> > 4k/sector disks, and that somehow in my configuring a .config, I
> > have crippled the kernels ability to deal with a miss-aligned disk
> > partition, and none of the installers is smart enough to align its
> > partitions.  The net results of course are 15M/sec write speeds on a
> > disk that can do 120M/sec when it does work. But first, it has to
> > boot.
> 
> Unlikely. Apart from fdisk the setup is basically invisible. The drive
> reports a block size and an offset. The firmware offset is chosen so
> that the chassic DOS alignments in fdisk happen to just fall nicely on
> 4K boundaries for partition starts.
> 
> There is nothing special the OS does to deal with ATA/SATA 4K sectors.
> 
> Alan

Good to know Alan, thanks. I'll turn my flashlight in a different 
direction then.

Cheers, Gene Heskett
-- 
"There are four boxes to be used in defense of liberty:
 soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
Genes Web page <http://geneslinuxbox.net:6309/gene>
US V Castleman, SCOTUS, Mar 2014 is grounds for Impeaching SCOTUS

Re: 64 bit kernel won't mount /

[Phillip Susi]

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Hash: SHA512

On 01/22/2015 10:34 AM, One Thousand Gnomes wrote:
> Unlikely. Apart from fdisk the setup is basically invisible. The
> drive reports a block size and an offset. The firmware offset is
> chosen so that the chassic DOS alignments in fdisk happen to just
> fall nicely on 4K boundaries for partition starts.
> 
> There is nothing special the OS does to deal with ATA/SATA 4K
> sectors.

Incorrect: the kernel bogus/synthetic "geometry" is the maximum
allowed of 63 sectors per track, and the old dos default alignment for
the first partition on the disk places its start at sector 63, which
is not 4k aligned.  The special thing that partitioning tools have to
do is to align the partition start to a 4k boundary.  For several
years now, parted has defaulted to 1 MiB alignment, like Windows has
done, which gives a 4k alignment.  I don't recall if Ubuntu 10.04 is
old enough to predate this change.  You certainly do NOT want to use
the cylinder alignment option in gparted.


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Re: 64 bit kernel won't mount /

[One Thousand Gnomes]

On Sun, 25 Jan 2015 16:18:27 -0500
Phillip Susi <psusi@ubuntu.com> wrote:

> -----BEGIN PGP SIGNED MESSAGE-----
> Hash: SHA512
> 
> On 01/22/2015 10:34 AM, One Thousand Gnomes wrote:
> > Unlikely. Apart from fdisk the setup is basically invisible. The
> > drive reports a block size and an offset. The firmware offset is
> > chosen so that the chassic DOS alignments in fdisk happen to just
> > fall nicely on 4K boundaries for partition starts.
> > 
> > There is nothing special the OS does to deal with ATA/SATA 4K
> > sectors.
> 
> Incorrect: the kernel bogus/synthetic "geometry" is the maximum
> allowed of 63 sectors per track, and the old dos default alignment for
> the first partition on the disk places its start at sector 63, which
> is not 4k aligned.  The special thing that partitioning tools 

I guess if you count partitioning tools as the "OS" this is true, but by
the OS I meant "system call layer and below".

Alan