From: Peter Xu <peterx@redhat.com>
Date: Mon, 26 Aug 2024 20:43:37 +0000 (-0400)
Subject: mm: mark special bits for huge pfn mappings when inject
X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=3c8e44c9b369b3d422516b3f2bf47a6e3c61d1ea;p=users%2Fwilly%2Fxarray.git

mm: mark special bits for huge pfn mappings when inject

We need these special bits to be around on pfnmaps.  Mark properly for
!devmap case, reflecting that there's no page struct backing the entry.

Link: https://lkml.kernel.org/r/20240826204353.2228736-4-peterx@redhat.com
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Acked-by: David Hildenbrand <david@redhat.com>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Alex Williamson <alex.williamson@redhat.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christian Borntraeger <borntraeger@linux.ibm.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Gavin Shan <gshan@redhat.com>
Cc: Gerald Schaefer <gerald.schaefer@linux.ibm.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Niklas Schnelle <schnelle@linux.ibm.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Sean Christopherson <seanjc@google.com>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index a4a14b81e013..f0983b17621c 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -1370,6 +1370,8 @@ static void insert_pfn_pmd(struct vm_area_struct *vma, unsigned long addr,
 	entry = pmd_mkhuge(pfn_t_pmd(pfn, prot));
 	if (pfn_t_devmap(pfn))
 		entry = pmd_mkdevmap(entry);
+	else
+		entry = pmd_mkspecial(entry);
 	if (write) {
 		entry = pmd_mkyoung(pmd_mkdirty(entry));
 		entry = maybe_pmd_mkwrite(entry, vma);
@@ -1466,6 +1468,8 @@ static void insert_pfn_pud(struct vm_area_struct *vma, unsigned long addr,
 	entry = pud_mkhuge(pfn_t_pud(pfn, prot));
 	if (pfn_t_devmap(pfn))
 		entry = pud_mkdevmap(entry);
+	else
+		entry = pud_mkspecial(entry);
 	if (write) {
 		entry = pud_mkyoung(pud_mkdirty(entry));
 		entry = maybe_pud_mkwrite(entry, vma);