Red Hat Bugzilla – Bug 50856
Secondary PCI bus not seen on Compaq Proliant 6400
Last modified: 2007-04-18 12:35:28 EDT
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Description of problem:
PCI network card is not seen in secondary PCI bus. When moved to the
Primary PCI bus it appears. 7.1 on this same Proliant 6400 did not have
this problem. lspci does not seem to show cards or PCI Hot Plug device
from the secondary PCI bus. The 6400 is based on a Intel 450NX chipset.
Steps to Reproduce:
1.Put a PCI card in a secondary PCI bus slot
3.OS does not see the card and lspci does not show it
Additional info: Machine is located in Compaq lab at Red Hat
This defect is considered MUST-FIX for Fairfax
The fact that it's the hotplug part of the system is interesting.
Is this by chance the enterprise kernel ?
Created attachment 27533 [details]
lspci -v output from machine booted with stock 2.4.6 kernel
The install created a -smp kernel entry. During the install I originally had
the NIC in the secondary PCI bus, and the install did not see it. That is when
I first noticed the problem. I moved the NIC to the primary PCI bus to make is
All the slots in the Proliant 6400 are Hot Plug.
I created a kernel from a stock 2.4.6 kernel tree and booted it. The secondary
PCI bus shows up with that kernel, but does not with the install built
2.4.6-3.1-smp kernel. I am attaching lspci output from the stock 2.4.6 kernel
and the 2.4.6-3.1-smp kernel. The stock 2.4.6 kernel shows two PCI-Hot plug
devices, while the 2.4.6-3.1-smp kernel shows just one.
Could you try installing the enterprise kernel ?
That one has hotplug PCI enabled
Created attachment 27534 [details]
lspci -v output from machine booted with 2.4.6-3.1smp kernel
Installed Enterprise kernel rpm from CD 1. It failed to boot with:
freeing unused memory
Kernel Panic no init found try passing init= to kernel
Ealier boot messages:
pivot_root:pivot_root (/sysroot, /sysroot/initrd) failed:2
error 19 mounting ext2
I created an entry in grub.boot that used the new kernel image and initrd that
were installed by the rpm. Maybe I didn't set something up correctly. Any
Looks like you are using the wrong initrd. The -enterprise kernel installs it's
own initrd, which is different from the smp one.
Created attachment 28115 [details]
lilo.conf (not grub as stated earlier) used to boot linux_ent entry. Initrd file used was the one installed by Enterprise rpm.
- Tried installing Roswell2 on the machine. Still didn't see the secondary PCI
- Tried booting with the enterprise kernel from Roswell2. Still didn't see
secondary PCI bus.
The issue is evident at install time because the kernel booted during the
install process does not see the NIC and cciss controller in the secondary bus
and therefore does not allow NIC configuration and does not load the cciss driver.
Went back and started an install from a 7.1 CD and the install saw the NIC and
asked for configuration info, and the cciss driver was loaded during install
kernel boot. So the kernel on the 7.1CD is seeing the secondary PCI bus correctly.
Have now verified that this behavior was introduced between
2.4.2-2 and 2.4.3-12; 2.4.2-2 shows the full lspci output and
2.4.3-12 has the truncated lspci output that shows nothing on
the secondary bus.
2.4.3-6 kernel works
Also see Bug #50755
Fixed in 2.4.7-2.8 and later