linux-kernel - [PATCH 03/30] mm/mmap: Add new config ARCH_HAS_VM_GET_PAGE

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]

Date:   Mon, 14 Feb 2022 08:00:26 +0530
From:   Anshuman Khandual <anshuman.khandual@....com>
To:     linux-mm@...ck.org
Cc:     linux-kernel@...r.kernel.org,
        Anshuman Khandual <anshuman.khandual@....com>,
        Christoph Hellwig <hch@...radead.org>,
        Andrew Morton <akpm@...ux-foundation.org>,
        linux-arch@...r.kernel.org
Subject: [PATCH 03/30] mm/mmap: Add new config ARCH_HAS_VM_GET_PAGE_PROT

Add a new config ARCH_HAS_VM_GET_PAGE_PROT, which when subscribed enables a
given platform to define its own vm_get_page_prot(). This framework will
help remove protection_map[] dependency going forward.

Cc: Andrew Morton <akpm@...ux-foundation.org>
Cc: linux-mm@...ck.org
Cc: linux-kernel@...r.kernel.org
Suggested-by: Christoph Hellwig <hch@...radead.org>
Signed-off-by: Anshuman Khandual <anshuman.khandual@....com>
---
 mm/Kconfig | 3 +++
 mm/mmap.c  | 2 ++
 2 files changed, 5 insertions(+)

diff --git a/mm/Kconfig b/mm/Kconfig
index 257ed9c86de3..fa436478a94c 100644
--- a/mm/Kconfig
+++ b/mm/Kconfig
@@ -747,6 +747,9 @@ config ARCH_HAS_CACHE_LINE_SIZE
 config ARCH_HAS_FILTER_PGPROT
 	bool
 
+config ARCH_HAS_VM_GET_PAGE_PROT
+	bool
+
 config ARCH_HAS_PTE_DEVMAP
 	bool
 
diff --git a/mm/mmap.c b/mm/mmap.c
index 670c68f5fbf1..ffd70a0c8ddf 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -81,6 +81,7 @@ static void unmap_region(struct mm_struct *mm,
 		struct vm_area_struct *vma, struct vm_area_struct *prev,
 		unsigned long start, unsigned long end);
 
+#ifndef CONFIG_ARCH_HAS_VM_GET_PAGE_PROT
 /* description of effects of mapping type and prot in current implementation.
  * this is due to the limited x86 page protection hardware.  The expected
  * behavior is in parens:
@@ -136,6 +137,7 @@ pgprot_t vm_get_page_prot(unsigned long vm_flags)
 	return arch_filter_pgprot(ret);
 }
 EXPORT_SYMBOL(vm_get_page_prot);
+#endif	/* CONFIG_ARCH_HAS_VM_GET_PAGE_PROT */
 
 static pgprot_t vm_pgprot_modify(pgprot_t oldprot, unsigned long vm_flags)
 {
-- 
2.25.1