On Sun, Mar 24, 2024 at 11:31:39AM +0100, Ingo Molnar wrote:
- Steve Wahl steve.wahl@hpe.com wrote:
Some systems have ACPI tables that don't include everything that needs to be mapped for a successful kexec. These systems rely on identity maps that include the full gigabyte surrounding any smaller region requested for kexec success. Without this, they fail to kexec and end up doing a full firmware reboot.
So, reduce the use of GB pages only on systems where this is known to be necessary (specifically, UV systems).
Signed-off-by: Steve Wahl steve.wahl@hpe.com Fixes: d794734c9bbf ("x86/mm/ident_map: Use gbpages only where full GB page should be mapped.") Reported-by: Pavin Joseph me@pavinjoseph.com
Sigh, why was d794734c9bbf marked for a -stable backport? The commit never explains ...
If it's broken, it should be reverted - instead of trying to partially revert and then maybe break some other systems.
When there's boot breakage with new patches, we back out the bad patch and re-try in 99.9% of the cases.
Fine with me, especially as you've already done the revert. :-)
I will create a new patch that combines the two. If you have any specific actions you'd like to be sure I do for this, let me know.
Thanks,
--> Steve Wahl