2.6.14, udev: unknown symbols for ehci_hcd

2.6.14, udev: unknown symbols for ehci_hcd

[Harald Dunkel]

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Hi folks,

I can't say since when this problem is in, but currently
I get error messages about unknown symbols at boot time
(after mounting the root disk, as it seems):

:
:
scsi0 : sata_sil
ata2: no device found (phy stat 00000000)
scsi1 : sata_sil
  Vendor: ATA       Model: SAMSUNG SP1614C   Rev: SW10
  Type:   Direct-Access                      ANSI SCSI revision: 05
SCSI device sda: 312581808 512-byte hdwr sectors (160042 MB)
SCSI device sda: drive cache: write back
SCSI device sda: 312581808 512-byte hdwr sectors (160042 MB)
SCSI device sda: drive cache: write back
 sda: sda1 sda2 sda3 sda4
Attached scsi disk sda at scsi0, channel 0, id 0, lun 0
ReiserFS: sda1: found reiserfs format "3.6" with standard journal
ReiserFS: sda1: using ordered data mode
ReiserFS: sda1: journal params: device sda1, size 8192, journal first block 18, max trans len 1024, max batch 900, max commit age 30, max trans age 30
ReiserFS: sda1: checking transaction log (sda1)
ReiserFS: sda1: Using r5 hash to sort names
NET: Registered protocol family 1
parport: PnPBIOS parport detected.
parport0: PC-style at 0x378, irq 7 [PCSPP,TRISTATE]
usbcore: registered new driver usbfs
usbcore: registered new driver hub
ehci_hcd: Unknown symbol usb_hcd_pci_suspend
ehci_hcd: Unknown symbol usb_free_urb
ehci_hcd: Unknown symbol usb_hub_tt_clear_buffer
ehci_hcd: Unknown symbol usb_hcd_pci_probe
ehci_hcd: Unknown symbol usb_disabled
ehci_hcd: Unknown symbol usb_unlock_device
ehci_hcd: Unknown symbol usb_put_dev
ehci_hcd: Unknown symbol usb_get_dev
:

If I modprobe ehci_hcd later, then there is no error message.
It is loaded as expected.

uname -a:
Linux pluto 2.6.14 #1 PREEMPT Sat Nov 5 08:47:20 CET 2005 x86_64 GNU/Linux
udev is version 0.071-1.


???

Regards

Harri


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Re: 2.6.14, udev: unknown symbols for ehci_hcd

[Greg KH]

On Sat, Nov 05, 2005 at 04:37:32PM +0100, Harald Dunkel wrote:
> Hi folks,
> 
> I can't say since when this problem is in, but currently
> I get error messages about unknown symbols at boot time
> (after mounting the root disk, as it seems):

Are you using Debian?

thanks,

greg k-h

Re: 2.6.14, udev: unknown symbols for ehci_hcd

[Kay Sievers]

On Sat, Nov 05, 2005 at 04:37:32PM +0100, Harald Dunkel wrote:
> I can't say since when this problem is in, but currently
> I get error messages about unknown symbols at boot time
> (after mounting the root disk, as it seems):
> :
> scsi0 : sata_sil
> ata2: no device found (phy stat 00000000)
> scsi1 : sata_sil
>   Vendor: ATA       Model: SAMSUNG SP1614C   Rev: SW10
>   Type:   Direct-Access                      ANSI SCSI revision: 05
> SCSI device sda: 312581808 512-byte hdwr sectors (160042 MB)
> SCSI device sda: drive cache: write back
> SCSI device sda: 312581808 512-byte hdwr sectors (160042 MB)
> SCSI device sda: drive cache: write back
>  sda: sda1 sda2 sda3 sda4
> Attached scsi disk sda at scsi0, channel 0, id 0, lun 0
> ReiserFS: sda1: found reiserfs format "3.6" with standard journal
> ReiserFS: sda1: using ordered data mode
> ReiserFS: sda1: journal params: device sda1, size 8192, journal first block 18, max trans len 1024, max batch 900, max commit age 30, max trans age 30
> ReiserFS: sda1: checking transaction log (sda1)
> ReiserFS: sda1: Using r5 hash to sort names
> NET: Registered protocol family 1
> parport: PnPBIOS parport detected.
> parport0: PC-style at 0x378, irq 7 [PCSPP,TRISTATE]
> usbcore: registered new driver usbfs
> usbcore: registered new driver hub
> ehci_hcd: Unknown symbol usb_hcd_pci_suspend
> ehci_hcd: Unknown symbol usb_free_urb
> ehci_hcd: Unknown symbol usb_hub_tt_clear_buffer
> ehci_hcd: Unknown symbol usb_hcd_pci_probe
> ehci_hcd: Unknown symbol usb_disabled
> ehci_hcd: Unknown symbol usb_unlock_device
> ehci_hcd: Unknown symbol usb_put_dev
> ehci_hcd: Unknown symbol usb_get_dev
> :
> 
> If I modprobe ehci_hcd later, then there is no error message.
> It is loaded as expected.
> 
> uname -a:
> Linux pluto 2.6.14 #1 PREEMPT Sat Nov 5 08:47:20 CET 2005 x86_64 GNU/Linux
> udev is version 0.071-1.

We (Debian and SUSE udev) are currently doing "coldplug" with udev,
sysfs and the kernel exported $MODALIAS value instead of the old
hotplug rc-scripts. Sysfs is scanned for all devices and hotplug
events are synthesized, or with kernel 2.6.14+ are just triggered
by a "uevent" file in sysfs. These events look like the same hotplug
event as it happened (but was lost in initramfs) at device creation
time. This approach does a heavy parallel module loading, which
may nobody have ever tried before and seen this "bug" ...

I've got these messages several times on the experimental SUSE too,
but can't reproduce it so far, even without Rusty's patch to modprobe
they have disappeared. See here for the details:
  http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=333052

Thanks,
Kay

Re: 2.6.14, udev: unknown symbols for ehci_hcd

[Pozsar Balazs]

On Sat, Nov 05, 2005 at 06:31:04PM +0100, Kay Sievers wrote:
> I've got these messages several times on the experimental SUSE too,
> but can't reproduce it so far, even without Rusty's patch to modprobe
> they have disappeared. See here for the details:
>   http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=333052


Just to let you know, I've also met this problem (on another distro), 
and did not know about this bugreport until now.
So I've done another workaround: modprobe already parses /proc/modules 
to check whether the modules needed are already loaded, and this file 
also shows us the state of the modules, being "Loading", "Live" or 
"Unloading".

With my patch, modprobe waits until the needed modules come out of the 
"Loading" or "Unloading" state.


-- 
pozsy


--- module-init-tools-3.2-pre4.orig/modprobe.c	2005-05-08 09:38:52.000000000 +0200
+++ module-init-tools-3.2-pre4/modprobe.c	2005-10-24 13:19:39.000000000 +0200
@@ -363,6 +363,7 @@
 	FILE *proc_modules;
 	char *line;
 
+start:
 	/* Might not be mounted yet.  Don't fail. */
 	proc_modules = fopen("/proc/modules", "r");
 	if (!proc_modules)
@@ -373,12 +374,31 @@
 
 		if (entry && strcmp(entry, modname) == 0) {
 			/* If it exists, usecount is the third entry. */
-			if (usecount) {
-				entry = strtok(NULL, " \n");
-				if (entry
-				    && (entry = strtok(NULL, " \n")) != NULL)
+			if (!(entry = strtok(NULL, " \n")))
+				goto out;
+
+			if (!(entry = strtok(NULL, " \n"))) /* usecount */
+				goto out;
+			else
+				if (usecount)
 					*usecount = atoi(entry);
+
+			if (!(entry = strtok(NULL, " \n"))) /* "-" */
+				goto out;
+
+			if (!(entry = strtok(NULL, " \n"))) /* status */
+				goto out;
+			else {
+				if (!strcmp(entry, "Loading") || !strcmp(entry, "Unloading")) {
+					usleep(100000);
+					free(line);
+					fclose(proc_modules);
+					goto start;
+				}
+				goto out;
 			}
+
+		out:
 			free(line);
 			fclose(proc_modules);
 			return 1;

Re: 2.6.14, udev: unknown symbols for ehci_hcd

[Rusty Russell]

On Sat, 2005-11-05 at 19:48 +0100, Pozsar Balazs wrote:
> On Sat, Nov 05, 2005 at 06:31:04PM +0100, Kay Sievers wrote:
> > I've got these messages several times on the experimental SUSE too,
> > but can't reproduce it so far, even without Rusty's patch to modprobe
> > they have disappeared. See here for the details:
> >   http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=333052
> 
> 
> Just to let you know, I've also met this problem (on another distro), 
> and did not know about this bugreport until now.
> So I've done another workaround: modprobe already parses /proc/modules 
> to check whether the modules needed are already loaded, and this file 
> also shows us the state of the modules, being "Loading", "Live" or 
> "Unloading".
> 
> With my patch, modprobe waits until the needed modules come out of the 
> "Loading" or "Unloading" state.

Yes, this was going to be my solution.  However, we only need to resort
to this is locking fails (read-only root filesystem).

Rusty.
-- 
A bad analogy is like a leaky screwdriver -- Richard Braakman

Re: 2.6.14, udev: unknown symbols for ehci_hcd

[Harald Dunkel]

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Greg KH wrote:
> On Sat, Nov 05, 2005 at 04:37:32PM +0100, Harald Dunkel wrote:
> 
>>Hi folks,
>>
>>I can't say since when this problem is in, but currently
>>I get error messages about unknown symbols at boot time
>>(after mounting the root disk, as it seems):
> 
> 
> Are you using Debian?
> 
Of course :=)


Regards

Harri

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Re: Bug#333052: 2.6.14, udev: unknown symbols for ehci_hcd

[Harald Dunkel]

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Pozsar Balazs wrote:
> On Sat, Nov 05, 2005 at 06:31:04PM +0100, Kay Sievers wrote:
> 
> 
> With my patch, modprobe waits until the needed modules come out of the 
> "Loading" or "Unloading" state.
> 
> 

For testing I have added it to Debian's
module-init-tools 3.2-pre9. Works for me.


Regards

Harri

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Re: Bug#333052: 2.6.14, udev: unknown symbols for ehci_hcd

[Harald Dunkel]

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Harald Dunkel wrote:
> 
> For testing I have added it to Debian's
> module-init-tools 3.2-pre9. Works for me.
> 

No, it doesn't. After the 3rd reboot the
problem was back.


Regards

Harri

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Re: Bug#333052: 2.6.14, udev: unknown symbols for ehci_hcd

[Pozsar Balazs]

On Sun, Nov 06, 2005 at 03:50:05PM +0100, Harald Dunkel wrote:
> Harald Dunkel wrote:
> > 
> > For testing I have added it to Debian's
> > module-init-tools 3.2-pre9. Works for me.
> > 
> 
> No, it doesn't. After the 3rd reboot the
> problem was back.

Well, that's really wierd, It Should Work(tm) :)
Did you apply both patches (Rusty's + mine), or only the latter?

Could you send me debug output please? The first time I met the problem, 
I used a modprobe wrapper which dumped /proc/modules and modprobe 
stdout/stderr to a temp file.

I would like to also mention, that my patch leaves a very little time 
window open, but that's only a problem if module unloading is also 
happening: after parsing /proc/modules, but before actually loading the 
module, it is possible that an rmmod unloads (starts to unload) a 
dependant module. But this does not affect booting.


-- 
pozsy

Re: 2.6.14, udev: unknown symbols for ehci_hcd

[Gustavo Guillermo Pérez]

El Sábado, 5 de Noviembre de 2005 23:59, escribió:
> Greg KH wrote:
> > On Sat, Nov 05, 2005 at 04:37:32PM +0100, Harald Dunkel wrote:
> >>Hi folks,
> >>
> >>I can't say since when this problem is in, but currently
> >>I get error messages about unknown symbols at boot time
> >>(after mounting the root disk, as it seems):
> >
> > Are you using Debian?
>
> Of course :=)

I was having that problem using busybox insmod, changing to latest kernel 
tools was fixed for me, I don't know why, but in my case was a ramdisk to 
load sata drivers before mounting the root disk. Anyway module-init-tools is 
not too bigger even building them with glibc instead uClibc as static 
binaries.

:)
-- 
Gustavo Guillermo Pérez
Compunauta uLinux
www.compunauta.com

Re: Bug#333052: 2.6.14, udev: unknown symbols for ehci_hcd

[Harald Dunkel]

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Pozsar Balazs wrote:
> 
> Well, that's really wierd, It Should Work(tm) :)
> Did you apply both patches (Rusty's + mine), or only the latter?
> 

I hadn't seen Rusty's patch on Debian's bts, until you mentioned
it. I have applied both patches now, and rebooted twice: By now
it worked. But that's what I thought before.

> Could you send me debug output please? The first time I met the problem, 
> I used a modprobe wrapper which dumped /proc/modules and modprobe 
> stdout/stderr to a temp file.
> 
If the problem comes back then I will do.

> I would like to also mention, that my patch leaves a very little time 
> window open, but that's only a problem if module unloading is also 
> happening: after parsing /proc/modules, but before actually loading the 
> module, it is possible that an rmmod unloads (starts to unload) a 
> dependant module. But this does not affect booting.
> 
> 

Are there several modprobe's running in parallel? Or does modprobe
return SUCCESS while the kernel is still busy "making the module
usable somehow"?


Regards

Harri

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Re: Bug#333052: 2.6.14, udev: unknown symbols for ehci_hcd

[Marco d'Itri]

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On Nov 06, Harald Dunkel <harald.dunkel@t-online.de> wrote:

> I hadn't seen Rusty's patch on Debian's bts, until you mentioned
> it. I have applied both patches now, and rebooted twice: By now
> it worked. But that's what I thought before.
It cannot be relevant, because when the bug is triggered / is still
read-only.

> Are there several modprobe's running in parallel? Or does modprobe
Yes.

-- 
ciao,
Marco

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Re: 2.6.14, udev: unknown symbols for ehci_hcd

[Greg KH]

On Sun, Nov 06, 2005 at 06:59:58AM +0100, Harald Dunkel wrote:
> Greg KH wrote:
> > On Sat, Nov 05, 2005 at 04:37:32PM +0100, Harald Dunkel wrote:
> > 
> >>Hi folks,
> >>
> >>I can't say since when this problem is in, but currently
> >>I get error messages about unknown symbols at boot time
> >>(after mounting the root disk, as it seems):
> > 
> > 
> > Are you using Debian?
> > 
> Of course :=)

This seems to be a Debian issue for some odd reason, I suggest filing a
bug against the udev package (or just tagging onto the existing bug for
this problem, I've seen it in there already...)

Good luck,

greg k-h

Re: Bug#333052: 2.6.14, udev: unknown symbols for ehci_hcd

[Harald Dunkel]

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Marco d'Itri wrote:
> 
>>Are there several modprobe's running in parallel? Or does modprobe
> 
> Yes.
> 
Is this supposed to be synchronized in user space, or in the
kernel?

Regards

Harri

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Re: 2.6.14, udev: unknown symbols for ehci_hcd

[Marco d'Itri]

On Nov 06, Greg KH <greg@kroah.com> wrote:

> This seems to be a Debian issue for some odd reason, I suggest filing a
> bug against the udev package (or just tagging onto the existing bug for
> this problem, I've seen it in there already...)
The reason this is usually seen only on Debian systems is that I am the
first one who shipped an udev package which runs many parallel modprobe
commands, but this is a genuine kernel/modprobe bug.

-- 
ciao,
Marco

Re: 2.6.14, udev: unknown symbols for ehci_hcd

[Greg KH]

On Mon, Nov 07, 2005 at 12:33:29PM +0100, Marco d'Itri wrote:
> On Nov 06, Greg KH <greg@kroah.com> wrote:
> 
> > This seems to be a Debian issue for some odd reason, I suggest filing a
> > bug against the udev package (or just tagging onto the existing bug for
> > this problem, I've seen it in there already...)
> The reason this is usually seen only on Debian systems is that I am the
> first one who shipped an udev package which runs many parallel modprobe
> commands, but this is a genuine kernel/modprobe bug.

I'm pretty sure OpenSuSE 10.0 does the same thing, and I don't think
anyone has reported the same kind of bugs there.  Makes me wonder what
is really happening here...

thanks,

greg k-h

Re: 2.6.14, udev: unknown symbols for ehci_hcd

[Pozsar Balazs]

On Mon, Nov 07, 2005 at 09:31:57AM -0800, Greg KH wrote:
> On Mon, Nov 07, 2005 at 12:33:29PM +0100, Marco d'Itri wrote:
> > On Nov 06, Greg KH <greg@kroah.com> wrote:
> > 
> > > This seems to be a Debian issue for some odd reason, I suggest filing a
> > > bug against the udev package (or just tagging onto the existing bug for
> > > this problem, I've seen it in there already...)
> > The reason this is usually seen only on Debian systems is that I am the
> > first one who shipped an udev package which runs many parallel modprobe
> > commands, but this is a genuine kernel/modprobe bug.
> 
> I'm pretty sure OpenSuSE 10.0 does the same thing, and I don't think
> anyone has reported the same kind of bugs there.  Makes me wonder what
> is really happening here...

If module A depends on module B, and "modprobe A" and "modprobe B" are 
run parallel, there is time window when module B is already listed in 
/proc/modules, but not completely loaded/initialized, it is in the state 
"Loading". At this point "modprobe A" checks /proc/modules if module B 
is already loaded, but it does not take into account that it is in the 
state "Loading" and not yet "Live". So it tries to load module A, but it 
fails, because there are missing symbols because module A did not 
register them yet.


-- 
pozsy

Re: 2.6.14, udev: unknown symbols for ehci_hcd

[Greg KH]

On Mon, Nov 07, 2005 at 08:07:38PM +0100, Pozsar Balazs wrote:
> On Mon, Nov 07, 2005 at 09:31:57AM -0800, Greg KH wrote:
> > On Mon, Nov 07, 2005 at 12:33:29PM +0100, Marco d'Itri wrote:
> > > On Nov 06, Greg KH <greg@kroah.com> wrote:
> > > 
> > > > This seems to be a Debian issue for some odd reason, I suggest filing a
> > > > bug against the udev package (or just tagging onto the existing bug for
> > > > this problem, I've seen it in there already...)
> > > The reason this is usually seen only on Debian systems is that I am the
> > > first one who shipped an udev package which runs many parallel modprobe
> > > commands, but this is a genuine kernel/modprobe bug.
> > 
> > I'm pretty sure OpenSuSE 10.0 does the same thing, and I don't think
> > anyone has reported the same kind of bugs there.  Makes me wonder what
> > is really happening here...
> 
> If module A depends on module B, and "modprobe A" and "modprobe B" are 
> run parallel

Why would they be run in parallel?  modprobe doesn't do this, why would
you?

> , there is time window when module B is already listed in 
> /proc/modules, but not completely loaded/initialized, it is in the state 
> "Loading". At this point "modprobe A" checks /proc/modules if module B 
> is already loaded, but it does not take into account that it is in the 
> state "Loading" and not yet "Live". So it tries to load module A, but it 
> fails, because there are missing symbols because module A did not 
> register them yet.

Sounds like a locking issue within the module core.  I thought we could
only load one at a time, otherwise we have other races within the
kernel.

thanks,

greg k-h

Re: 2.6.14, udev: unknown symbols for ehci_hcd

[Pozsar Balazs]

On Mon, Nov 07, 2005 at 11:12:14AM -0800, Greg KH wrote:
> On Mon, Nov 07, 2005 at 08:07:38PM +0100, Pozsar Balazs wrote:
> > On Mon, Nov 07, 2005 at 09:31:57AM -0800, Greg KH wrote:
> > > On Mon, Nov 07, 2005 at 12:33:29PM +0100, Marco d'Itri wrote:
> > > > On Nov 06, Greg KH <greg@kroah.com> wrote:
> > > > 
> > > > > This seems to be a Debian issue for some odd reason, I suggest filing a
> > > > > bug against the udev package (or just tagging onto the existing bug for
> > > > > this problem, I've seen it in there already...)
> > > > The reason this is usually seen only on Debian systems is that I am the
> > > > first one who shipped an udev package which runs many parallel modprobe
> > > > commands, but this is a genuine kernel/modprobe bug.
> > > 
> > > I'm pretty sure OpenSuSE 10.0 does the same thing, and I don't think
> > > anyone has reported the same kind of bugs there.  Makes me wonder what
> > > is really happening here...
> > 
> > If module A depends on module B, and "modprobe A" and "modprobe B" are 
> > run parallel
> 
> Why would they be run in parallel?  modprobe doesn't do this, why would
> you?

On my machine it happened while loading pcmcia modules. It was two 
modprobes running in parallel (invoked by udev), not 1 modprobe loading 
modules in parallel.

> > , there is time window when module B is already listed in 
> > /proc/modules, but not completely loaded/initialized, it is in the state 
> > "Loading". At this point "modprobe A" checks /proc/modules if module B 
> > is already loaded, but it does not take into account that it is in the 
> > state "Loading" and not yet "Live". So it tries to load module A, but it 
> > fails, because there are missing symbols because module A did not 
> > register them yet.
> 
> Sounds like a locking issue within the module core.  I thought we could
> only load one at a time, otherwise we have other races within the
> kernel.

That's what I thought too, but this is not the case it seems.


-- 
pozsy

Re: 2.6.14, udev: unknown symbols for ehci_hcd

[Greg KH]

On Mon, Nov 07, 2005 at 08:20:15PM +0100, Pozsar Balazs wrote:
> On Mon, Nov 07, 2005 at 11:12:14AM -0800, Greg KH wrote:
> > On Mon, Nov 07, 2005 at 08:07:38PM +0100, Pozsar Balazs wrote:
> > > On Mon, Nov 07, 2005 at 09:31:57AM -0800, Greg KH wrote:
> > > > On Mon, Nov 07, 2005 at 12:33:29PM +0100, Marco d'Itri wrote:
> > > > > On Nov 06, Greg KH <greg@kroah.com> wrote:
> > > > > 
> > > > > > This seems to be a Debian issue for some odd reason, I suggest filing a
> > > > > > bug against the udev package (or just tagging onto the existing bug for
> > > > > > this problem, I've seen it in there already...)
> > > > > The reason this is usually seen only on Debian systems is that I am the
> > > > > first one who shipped an udev package which runs many parallel modprobe
> > > > > commands, but this is a genuine kernel/modprobe bug.
> > > > 
> > > > I'm pretty sure OpenSuSE 10.0 does the same thing, and I don't think
> > > > anyone has reported the same kind of bugs there.  Makes me wonder what
> > > > is really happening here...
> > > 
> > > If module A depends on module B, and "modprobe A" and "modprobe B" are 
> > > run parallel
> > 
> > Why would they be run in parallel?  modprobe doesn't do this, why would
> > you?
> 
> On my machine it happened while loading pcmcia modules. It was two 
> modprobes running in parallel (invoked by udev), not 1 modprobe loading 
> modules in parallel.

Ah, ok, that explains how it is happening, thanks.

> > > , there is time window when module B is already listed in 
> > > /proc/modules, but not completely loaded/initialized, it is in the state 
> > > "Loading". At this point "modprobe A" checks /proc/modules if module B 
> > > is already loaded, but it does not take into account that it is in the 
> > > state "Loading" and not yet "Live". So it tries to load module A, but it 
> > > fails, because there are missing symbols because module A did not 
> > > register them yet.
> > 
> > Sounds like a locking issue within the module core.  I thought we could
> > only load one at a time, otherwise we have other races within the
> > kernel.
> 
> That's what I thought too, but this is not the case it seems.

Um, why not?  Rusty?

thanks,

greg k-h

Re: 2.6.14, udev: unknown symbols for ehci_hcd

[Marco d'Itri]

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On Nov 08, Rusty Russell <rusty@rustcorp.com.au> wrote:

> The current simple fix for that (thanks Pozsar!) is to poll while a
> module we rely on is still loading as indicated in /proc/modules.  This
> fix will be needed to cover existing kernels, even if we were to get
> fancy in new kernels.
I have *not* been able to verify this, but at least two people still
reported problems after using this patch.

-- 
ciao,
Marco

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Re: 2.6.14, udev: unknown symbols for ehci_hcd

[Rob Landley]

On Sunday 06 November 2005 11:03, Gustavo Guillermo Pérez wrote:
> El Sábado, 5 de Noviembre de 2005 23:59, escribió:
> > Greg KH wrote:
> > > On Sat, Nov 05, 2005 at 04:37:32PM +0100, Harald Dunkel wrote:
> > >>Hi folks,
> > >>
> > >>I can't say since when this problem is in, but currently
> > >>I get error messages about unknown symbols at boot time
> > >>(after mounting the root disk, as it seems):
> > >
> > > Are you using Debian?
> >
> > Of course :=)
>
> I was having that problem using busybox insmod, changing to latest kernel
> tools was fixed for me, I don't know why, but in my case was a ramdisk to
> load sata drivers before mounting the root disk. Anyway module-init-tools
> is not too bigger even building them with glibc instead uClibc as static
> binaries.
>
> :)

Which version of busybox?  (If something's wrong with it, I'm interested in 
fixing it.  Insmod underwent a lot of changes to support 2.6, and it took a 
while to stabilize again...)

Rob