[PATCH 0/5] Fixes for ITS mitigation and execmem

[Mike Rapoport]

From: "Mike Rapoport (Microsoft)" <rppt@xxxxxxxxxx>

Hi,

Jürgen Groß reported some bugs in interaction of ITS mitigation with
execmem [1] when running on a Xen PV guest.

These patches fix the issue by moving all the permissions management of
ITS memory allocated from execmem into ITS code.

I didn't test on a real Xen PV guest, but I emulated !PSE variant by
force-disabling the ROX cache in x86::execmem_arch_setup().

Peter, I took liberty to put your SoB in the patch that actually
implements the execmem permissions management in ITS, please let me know
if I need to update something about the authorship.

The patches are against v6.15.
They are also available in git:
https://web.git.kernel.org/pub/scm/linux/kernel/git/rppt/linux.git/log/?h=its-execmem/v1

[1] https://lore.kernel.org/all/20250528123557.12847-2-jgross@xxxxxxxx/

Juergen Gross (1):
  x86/mm/pat: don't collapse pages without PSE set

Mike Rapoport (Microsoft) (3):
  x86/Kconfig: only enable ROX cache in execmem when STRICT_MODULE_RWX is set
  x86/its: move its_pages array to struct mod_arch_specific
  Revert "mm/execmem: Unify early execmem_cache behaviour"

Peter Zijlstra (Intel) (1):
  x86/its: explicitly manage permissions for ITS pages

 arch/x86/Kconfig              |  2 +-
 arch/x86/include/asm/module.h |  8 ++++
 arch/x86/kernel/alternative.c | 89 ++++++++++++++++++++++++++---------
 arch/x86/mm/init_32.c         |  3 --
 arch/x86/mm/init_64.c         |  3 --
 arch/x86/mm/pat/set_memory.c  |  3 ++
 include/linux/execmem.h       |  8 +---
 include/linux/module.h        |  5 --
 mm/execmem.c                  | 40 ++--------------
 9 files changed, 82 insertions(+), 79 deletions(-)


base-commit: 0ff41df1cb268fc69e703a08a57ee14ae967d0ca
-- 
2.47.2