All RAM may not be mapped. Check the mapping for the main kernel
image and the locore if it exists.
Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
All RAM may not be mapped. Check the mapping for the main kernel
image and the locore if it exists.
Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
Show the page table layout for a user thread. This
may be somewhat different from a supervisor thread
especially if KPTI is enabled.
Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
We provide an option for low-memory systems to use a single set
of page tables for all threads. This is only supported if
KPTI and SMP are disabled. This configuration saves a considerable
amount of RAM, especially if multiple memory domains are used,
at a cost of context switching overhead.
Some caching techniques are used to reduce the amount of context
switch updates; the page tables aren't updated if switching to
a supervisor thread, and the page table configuration of the last
user thread switched in is cached.
Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
If KPTI is not enabled, then the US bit will be set for all
the default memory partitions in the _app_smem section.
The error printed when a mismatch occurs now shows the
expected flags.
Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
For boards with (relatively) large memory, the test which dumps
page tables takes a long time to finish. The default timeout of
sanitycheck is not enough for those boards. UP Squared board is
such a board. So limits to pagetable dumping to boards with
less than 32MB.
Fixes#28548
Signed-off-by: Daniel Leung <daniel.leung@intel.com>
We no longer plan to support a split address space with
the kernel in high memory and per-process address spaces.
Because of this, we can simplify some things. System RAM
is now always identity mapped at boot.
We no longer require any virtual-to-physical translation
for page tables, and can remove the dual-mapping logic
from the page table generation script since we won't need
to transition the instruction point off of physical
addresses.
CONFIG_KERNEL_VM_BASE and CONFIG_KERNEL_VM_LIMIT
have been removed. The kernel's address space always
starts at CONFIG_SRAM_BASE_ADDRESS, of a fixed size
specified by CONFIG_KERNEL_VM_SIZE.
Driver MMIOs and other uses of k_mem_map() are still
virtually mapped, and the later introduction of demand
paging will result in only a subset of system RAM being
a fixed identity mapping instead of all of it.
Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
For the moment, we validate the flags on all RAM pages,
ensure that NULL is never mapped, and show that dumping
page tables doesn't crash.
Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
Andrew Boie