linux-kernel - [PATCH 31/45] mm/mincore: Create mincore_pud_range to handle PUD-mapped hugetlb vmas

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20240704043132.28501-32-osalvador@suse.de>
Date: Thu,  4 Jul 2024 06:31:18 +0200
From: Oscar Salvador <osalvador@...e.de>
To: Andrew Morton <akpm@...ux-foundation.org>
Cc: linux-kernel@...r.kernel.org,
	linux-mm@...ck.org,
	Peter Xu <peterx@...hat.com>,
	Muchun Song <muchun.song@...ux.dev>,
	David Hildenbrand <david@...hat.com>,
	SeongJae Park <sj@...nel.org>,
	Miaohe Lin <linmiaohe@...wei.com>,
	Michal Hocko <mhocko@...e.com>,
	Matthew Wilcox <willy@...radead.org>,
	Christophe Leroy <christophe.leroy@...roup.eu>,
	Oscar Salvador <osalvador@...e.de>
Subject: [PATCH 31/45] mm/mincore: Create mincore_pud_range to handle PUD-mapped hugetlb vmas

Normal THP cannot be PUD-mapped (besides devmap), but hugetlb can, so create
mincore_pud_range in order to handle PUD-mapped hugetlb vmas.

Signed-off-by: Oscar Salvador <osalvador@...e.de>
---
 mm/mincore.c | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/mm/mincore.c b/mm/mincore.c
index 5154bc705f60..786df7246899 100644
--- a/mm/mincore.c
+++ b/mm/mincore.c
@@ -98,6 +98,25 @@ static int mincore_unmapped_range(unsigned long addr, unsigned long end,
 	return 0;
 }
 
+static int mincore_pud_range(pud_t *pud, unsigned long addr, unsigned long end,
+			     struct mm_walk *walk)
+{
+#ifdef CONFIG_PGTABLE_HAS_HUGE_LEAVES
+	spinlock_t *ptl;
+	unsigned char *vec = walk->private;
+	int nr = (end - addr) >> PAGE_SHIFT;
+	struct vm_area_struct *vma = walk->vma;
+
+	ptl = pud_huge_lock(pud, vma);
+	if (!ptl)
+		return 0;
+
+	memset(vec, 1, nr);
+	spin_unlock(ptl);
+#endif
+	return 0;
+}
+
 static int mincore_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end,
 			struct mm_walk *walk)
 {
@@ -175,6 +194,7 @@ static inline bool can_do_mincore(struct vm_area_struct *vma)
 }
 
 static const struct mm_walk_ops mincore_walk_ops = {
+	.pud_entry		= mincore_pud_range,
 	.pmd_entry		= mincore_pte_range,
 	.pte_hole		= mincore_unmapped_range,
 	.hugetlb_entry		= mincore_hugetlb,
-- 
2.26.2