Regressions in the last kernels

[werner]

During preparation and own testing for my distro; installation on computers for neighbours, by reclamations by users, I learned about the following problems of 2.6.26-rcX :

1) When compiling for i486,  one cannot select/configurate more memory than 4 GB, menuconfig don't show items with higher values.  My own computer/server has 8 GB, but when I compile the kernel with 4 GB and i486 then 'free' shows only 3.2 GB (no shared grafics, the grafic card has its own memory) ...

2) On some laptops, especially IBM/Centrinho laptops, 2.6.26-rcX dont find the CD devices, nor that from what was booted.   This problem is independend on the edd problem.  It wasn't present at the 2.6.25-rc9 kernel or earliers (i didn't test it on 2.6.25 defin.), but it's present at 2.6.26-rc4 and -rc5 (-rc6 i didnt test).  Just because of this problem it wasnt possible to install something on this kind laptop, and I had yesterday to make a new Install .iso with an older kernel as alternative:  ftp://ftp.uni-siegen.de/pub/sys-linux/SYS_Linux-0.23-rc3.iso    

Exactly happens the following:   BIOS finds correctly the CD drive for booting and boots, but later Linux dont find it (only older kernels), on some laptops.             I insert in the drive the Install DVD:  It boots, loads the kernel and the initrd correctly.   This is the small install / rescue system.  However, although everything present in /dev, inclusive the device nodes /dev/hdb  etc (but empty),  Linux don't find /dev/hdb f.ex. for mount it or calling with hdparm or anyhow else. Thus, also the system installation fails, because the packages or lzma-zipped system cannot be readed from the same CD what was used for boot and what BIOS found/managed ...     With exactly the same system/initrd, configuration etc everything the same but just change to an older kernel, everything works normally; thus this is a kernel regression

*** At this point, I want to suggest, that Linux should have a special devide node /dev/<anyname> on what one can mount ANYWAY and ANYHOW that boot device what BIOS used and understood to boot from, even when the hardware detection of Linux fails completely.   When bios managed it to read that device and to load the kernel and the initrd , then Linux should manage it too, to read from the same CD other files.  This is necessary in order to perform the installation anyway, even when Linux dont find hardware or the boot CD. ***  


Werner Landgraf
werner#guyane.dyn-o-saur.com
werner@xxxxxxxxxxxxx 

Linux  SYS   
0.23-rc3