Red Hat Bugzilla – Bug 30694
Use of dangerous parms for IDE disks
Last modified: 2007-04-18 12:31:58 EDT
While checking with hdparms I noticed that on my machine (with a VIA Apollo MVP3 chipset) you were using "dma=1 unmasq_irq=1". Unmasq_irq is supposed to be _very_dangerous and reportedly can cause MASSIVE data corruption. In addition these settings are enforceed directly in the kernel since I got them after a reboot with "noinitrd init=/bin/sh". This makes it still more dangerouus that if it were the result of an hdparm in the init scripts since there will be disk activity and possibly an fsck before we have the opportunity to turn this off. Please don't paly russian roulette with our hard disks.
The VIA driver _ITSELF_ turns that on unconditionally; regardless of the DMA setting. The maintainer of the driver most likely determined it was safe to do so with his driver. If we disable this, we run the risk of more corruption as the rest of the driver might assume it is always 1.