On Wed, 23 Sep 2009 17:49:22 +0200, Henrik Kretzschmar wrote: > Jean Delvare schrieb: > > > That's right, but it doesn't explain why i2c-piix4 crashes in the first > > place, not why merely loading it causes further lspci -xxx to crash > > when they did not beforehand. I admit I am totally clueless. > > > Sorry, I expressed myself a bit unclear. > > With _worked_ I meant the system crashed (thats what killer commands are for). > > lspci -xxx (and co) bring this system down in every case, module loaded or not. > Obvious this crash occuress when reading the config space in short periods. Ah, OK, thanks for the clarification. > lspci (or better proc-fs and sys-fs) do that, and i2c-piix4 does it sometimes. > > Looking at read() of drivers/pci/proc.c i had the idea of stalking the critical area with: > > #!/bin/sh > for i in `seq 100`; do > dd if=/proc/bus/pci/00/07.3 of=/dev/null bs=1 count=n 2>/dev/null; > done > > > I got no crashes with n == 192, but with n == 193 theres no reaction from the system. > > Maybe it's interesting, that (all the time after crashes) the screen > (in my case the console with a blinking cursor) can still be seen. > But no reaction on keyboard hits. I think it is typical of IRQ routing gone out to lunch. > Also strange is, that the device works well IF those two read accesses have not done the crash. > I'll test tomorrow without the second read access, just to know if it works. -- Jean Delvare -- To unsubscribe from this list: send the line "unsubscribe linux-i2c" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
