Greg Lehey wrote:
> Technical explanation: A buffer header gets corrupted between the
> time the top half of the driver issues the request to the disk
> driver, and when the I/O completes. Currently, the evidence is
> pointing towards the disk driver, but the corruption is of such an
> unusual nature that it's difficult to guess what's going on.
This type of bug sounds like a perfect candidate for using the
kernel's hardware debug support (on IA32), and would allow you to take
a trace trap and drop to the kernel debugger when anyone modifies the
buffer header, assuming you can cover the corrupted area with the 4
debug registers available, which can cover a range of 16 bytes, in 4
byte chunks. This is exactly the type of situation that inspired me
to add the support in the first place.
Hopefully, when I get a little bit of time, I can merge the code that
I use so that we can do this in a straight forward way from within the
kernel debugger.
-Brian
--
Brian Dean [EMAIL PROTECTED]
SAS Institute Inc. [EMAIL PROTECTED]
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