On 10/15/2017 11:56 PM, Simon Horman wrote:
On Thu, Oct 12, 2017 at 02:02:27PM -0700, David Daney wrote:
The OCTEON family of MIPS64 CPUs uses a PAGE_OFFSET of
0x8000000000000000ULL, which is differs from other CPUs.
Scan /proc/cpuinfo to see if the current system is "Octeon", if so,
patch the page_offset so that usable kdump core files are produced.
Signed-off-by: David Daney <david.daney@xxxxxxxxxx>
Is it possible to read this offset from the system rather than
checking for an Octeon CPU? It seems that such an approach, if possible,
would be somewhat more general.
Before implementing this scanning of /proc/cpuinfo, I thought long and
hard about this, and couldn't think of how the PAGE_OFFSET could be
derived from information available in userspace.
Ralf (MIPS maintainer) may have an idea, but these address bits don't
show up in /proc/kallsyms or any other file in /proc or /sys that I am
aware of.
David
