Comment 445 for bug 88746

Turns out the Intrepid standard kernel gives me the disconnects on my main desktop too, although they don't make the machine lose connectivity to the USB drives - things just work slowly for a brief moment and then everything stabilises again. This machine has an nVidia MCP73 chipset.

The max_sectors fix seem however to do the trick, so here is a udev rule that will make udev set the correct max_sectors on all USB drives automatically and while YMMV it does in fact work for me.

It seems like the safe thing is to default max_sectors to 128 instead of 240 as it works with more chipsets and doesn't require kernel workarounds.

Anyway, drop the following into /etc/udev/rules.d/81-usb_max_sectors.rules and make sure that the SUBSYSTEM line is in fact on one line and not broken into two.

# Set max_sectors to 128 for USB HDDs as the default 240 causes problems
#
SUBSYSTEM=="block", BUS=="usb", KERNEL=="sd*", RUN+="/bin/sh -c 'echo 128 > /sys/block/%k/device/max_sectors'"

I need this machine for work purposes so am a little hesitant to try out the jaunty kernel especially since the workaround works and the workaround can be implemented by policy as opposed to waiting for kernel support.