tree e1ef98e60c0f91fd59fc14f3983525d21c62760a
parent 4be0f4bf9943f5f6c84d1c13dee70b7442f99bd0
author Robert Zieba <robertzieba@google.com> 1649954175 -0600
committer Nick Vaccaro <nvaccaro@google.com> 1652370438 +0000

arch/x86: Add support for catching null dereferences through debug regs

This commit adds support for catching null dereferences and execution
through x86's debug registers. This is particularly useful when running
32-bit coreboot as paging is not enabled to catch these through page
faults. This commit adds three new configs to support this feature:
DEBUG_HW_BREAKPOINTS, DEBUG_NULL_DEREF_BREAKPOINTS and
DEBUG_NULL_DEREF_HALT.

BUG=b:223902046
TEST=Ran on nipperkin device, verifying that HW breakpoints work as
expected.

Change-Id: I113590689046a13c2a552741bbfe7668a834354a
Signed-off-by: Robert Zieba <robertzieba@google.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/63657
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Raul Rangel <rrangel@chromium.org>