On Sat, Jan 28, 2012 at 03:36:28PM +0530, Rabin Vincent wrote:
I have access to a system whose crashdump extraction mechanism
unfortunately trashes the first few hundred kilobytes of physical
memory, which includes the page tables at swapper_pg_dir.
crash does chug along and remains quite useful without these page tables
since much of the interesting information is in the direct mapped
region, but it disables the use of the unwind tables because it
fails to read the module unwind tables, which are placed at a
non-direct-mapped address.
The patch below allows unwind tables to be used only for core kernel
addresses if the module tables are inaccessible.
Alternatively, we could perhaps not attempt to read the
module unwind tables when --no_modules is specified.
IMHO crash should at least try to allow user to perform analysis even if it
cannot do V<->P translations via page tables. The patch looks good and makes
ARM port of crash a bit more tolerant so,
Acked-by: Mika Westerberg <mika.westerberg(a)iki.fi>
Thanks!