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
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.