GoogleCodeExporter
commented
8 years ago ok, now i remember this issue. the differences are in the return codes from the
nand driver that are stored after each page in the dump. each page is written
in the following format :
page data (usually 8192 bytes) + spare area (12 bytes) + iokit return code (4
bytes) + other return code (4 bytes)
i assume the "dumpedPageSize" in your plist file is set to 8212 (8192+12+8).
with that assumption i verified that each of the offsets you posted are in fact
the offsets of the first byte of the "other return code" value.
When we read a page through the kernel driver, there are two return codes : the
first one is a standard iokit return code, that can be used to check if a page
is blank or not (kIOReturnUnformattedMedia). To be honest i don't know yet what
the second return code is for, but i now remember that i encountered the same
issue as you when testing. Maybe it indicates the "number of errors corrected
while reading the page" but i have to clear this out.
So i guess it was a bad idea to include this in the dump, because even if there
is no difference in the actual data (page data + spare), the second return code
seems to change from one acquisition to another. I'll probably change the dump
format in a future update to remove this.
Thanks a lot for reporting this.
Original comment by jean.sig...@gmail.com on 15 Feb 2013 at 9:48
- Changed state: Accepted
Attachments:
Original issue reported on code.google.com by
kay...@gmail.comon 15 Feb 2013 at 8:52