Wow! A hole in linuxbios PCI mastery setup?

Ronald G. Minnich rminnich at lanl.gov
Tue Jan 14 09:42:00 CET 2003


we don't turn on bus master as that could be very hazardous to your health 
-- imagine an unitialized PCI device coming up with bus master enabled. It 
is at that point allowed to do DMA cycles to RAM without having been 
initialized by a driver. OUCH. 

In my opinion if the driver is not turning on bus master it is a buggy 
driver. If the device comes up with bus master enabled it is a buggy 
device. Ollie has pointed this out too. There's a lot of buggy PCI 
hardware in existence. 

I think the Award BIOS is buggy, possibly intentionally, to deal with 
buggy drivers (there are lots of BIOS patches that are in there, I am 
told, to fix buggy device drivers in Windows). 

I would recommend fixing the 802.11 driver, rather than modifying 
LinuxBIOS. But let's see what other people say.

ron




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