+ x86-mm-pat-remove-strict_prot-parameter-from-reserve_pfn_range.patch added to mm-new branch

+ x86-mm-pat-remove-strict_prot-parameter-from-reserve_pfn_range.patch added to mm-new branch

[Andrew Morton]

The patch titled
     Subject: x86/mm/pat: remove strict_prot parameter from reserve_pfn_range()
has been added to the -mm mm-new branch.  Its filename is
     x86-mm-pat-remove-strict_prot-parameter-from-reserve_pfn_range.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/x86-mm-pat-remove-strict_prot-parameter-from-reserve_pfn_range.patch

This patch will later appear in the mm-new branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Note, mm-new is a provisional staging ground for work-in-progress
patches, and acceptance into mm-new is a notification for others take
notice and to finish up reviews.  Please do not hesitate to respond to
review feedback and post updated versions to replace or incrementally
fixup patches in mm-new.

Before you just go and hit "reply", please:
   a) Consider who else should be cc'ed
   b) Prefer to cc a suitable mailing list as well
   c) Ideally: find the original patch on the mailing list and do a
      reply-to-all to that, adding suitable additional cc's

*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***

The -mm tree is included into linux-next via the mm-everything
branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
and is updated there every 2-3 working days

------------------------------------------------------
From: David Hildenbrand <david@redhat.com>
Subject: x86/mm/pat: remove strict_prot parameter from reserve_pfn_range()
Date: Mon, 12 May 2025 14:34:20 +0200

Always set to 0, so let's remove it.

Link: https://lkml.kernel.org/r/20250512123424.637989-8-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Acked-by: Ingo Molnar <mingo@kernel.org> # x86 bits
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Betkov <bp@alien8.de>
Cc: Dave Airlie <airlied@gmail.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Jann Horn <jannh@google.com>
Cc: Jonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: "Masami Hiramatsu (Google)" <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleinxer <tglx@linutronix.de>
Cc: Tvrtko Ursulin <tursulin@ursulin.net>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 arch/x86/mm/pat/memtype.c |   12 +++---------
 1 file changed, 3 insertions(+), 9 deletions(-)

--- a/arch/x86/mm/pat/memtype.c~x86-mm-pat-remove-strict_prot-parameter-from-reserve_pfn_range
+++ a/arch/x86/mm/pat/memtype.c
@@ -858,8 +858,7 @@ int memtype_kernel_map_sync(u64 base, un
  * Reserved non RAM regions only and after successful memtype_reserve,
  * this func also keeps identity mapping (if any) in sync with this new prot.
  */
-static int reserve_pfn_range(u64 paddr, unsigned long size, pgprot_t *vma_prot,
-				int strict_prot)
+static int reserve_pfn_range(u64 paddr, unsigned long size, pgprot_t *vma_prot)
 {
 	int is_ram = 0;
 	int ret;
@@ -895,8 +894,7 @@ static int reserve_pfn_range(u64 paddr,
 		return ret;
 
 	if (pcm != want_pcm) {
-		if (strict_prot ||
-		    !is_new_memtype_allowed(paddr, size, want_pcm, pcm)) {
+		if (!is_new_memtype_allowed(paddr, size, want_pcm, pcm)) {
 			memtype_free(paddr, paddr + size);
 			pr_err("x86/PAT: %s:%d map pfn expected mapping type %s for [mem %#010Lx-%#010Lx], got %s\n",
 			       current->comm, current->pid,
@@ -906,10 +904,6 @@ static int reserve_pfn_range(u64 paddr,
 			       cattr_name(pcm));
 			return -EINVAL;
 		}
-		/*
-		 * We allow returning different type than the one requested in
-		 * non strict case.
-		 */
 		pgprot_set_cachemode(vma_prot, pcm);
 	}
 
@@ -959,7 +953,7 @@ int pfnmap_track(unsigned long pfn, unsi
 {
 	const resource_size_t paddr = (resource_size_t)pfn << PAGE_SHIFT;
 
-	return reserve_pfn_range(paddr, size, prot, 0);
+	return reserve_pfn_range(paddr, size, prot);
 }
 
 void pfnmap_untrack(unsigned long pfn, unsigned long size)
_

Patches currently in -mm which might be from david@redhat.com are

selftests-mm-add-simple-vm_pfnmap-tests-based-on-mmaping-dev-mem.patch
x86-mm-pat-factor-out-setting-cachemode-into-pgprot_set_cachemode.patch
mm-convert-track_pfn_insert-to-pfnmap_setup_cachemode.patch
mm-introduce-pfnmap_track-and-pfnmap_untrack-and-use-them-for-memremap.patch
mm-convert-vm_pfnmap-tracking-to-pfnmap_track-pfnmap_untrack.patch
x86-mm-pat-remove-old-pfnmap-tracking-interface.patch
mm-remove-vm_pat.patch
x86-mm-pat-remove-strict_prot-parameter-from-reserve_pfn_range.patch
x86-mm-pat-remove-memtype__match.patch
x86-mm-pat-inline-memtype_match-into-memtype_erase.patch
drm-i915-track_pfn-pfnmap-tracking.patch
mm-io-mapping-track_pfn-pfnmap-tracking.patch