[Date Prev][Date Next] [Thread Prev][Thread Next] [Date Index] [Thread Index]

Re: boot parameter libata.force=1.5Gbps not recognized

Selim T. Erdogan,  3.10.2012:
> Adding "libata.force=1.5Gbps" to the boot parameters for the installer 
> doesn't work.  It leads to a message saying "unknown parameter 5Gbps".
> (Trying 3.0Gbps leads to "unknown parameter 0Gbps" so it looks like it 
> could be a parsing issue.)
> Details:
> I have a Sony Vaio VGN-NS140E laptop that was working fine with sid 
> until its hard drive died recently, so I got an SSD and prepared a usb 
> stick with the wheezy beta2 installer.  The install was okay generally, 
> though there were many serious errors when accessing the drive, making 
> the system unusable.  Searching online, I found out that some computers,
> even ones whose SATA controllers are supposedly capable of 3Gbps, can 
> only manage 1.5Gbps and have problems with the auto-negotiation to drop 
> from 3Gbps to 1.5Gbps.  The old hard drive that came out of the laptop 
> had a jumper on it, limiting its speed to 1.5Gbps, but this new SSD 
> doesn't have such a jumper setting, as far as I could find out.  
> To test that dropping to 1.5Gbps would solve the problems, I tried 
> installing Linux Mint.  It recognized the boot parameter correctly, 
> leading to no drive errors at all and good performance (within the 
> bounds of 1.5Gbps, or course --- still much faster than my old hard 
> drive).  The kernel for Mint was 3.2.0-23 and the one in the Debian 
> installer was 3.2.0-3, I think.  (By the way, without that parameter, 
> Mint also had massive problems with the new drive.)

It turns out this wasn't limited to just the installer.  It's a problem 
with the libkmod2 package.  Module parameters given in the kernel 
command line are parsed incorrectly if the parameter value has a '.' in 
it, like 1.5Gbps.  I filed a bug report with a fix:

Reply to: