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[1/3] mm: hugetlb: allow hugepages_supported to be architecture specific

Message ID 1474548015-16119-2-git-send-email-luis.henriques@canonical.com
State New
Headers show

Commit Message

Luis Henriques Sept. 22, 2016, 12:40 p.m. UTC 
From: Dominik Dingel <dingel@linux.vnet.ibm.com>

s390 has a constant hugepage size, by setting HPAGE_SHIFT we also change
e.g. the pageblock_order, which should be independent in respect to
hugepage support.

With this patch every architecture is free to define how to check
for hugepage support.

Signed-off-by: Dominik Dingel <dingel@linux.vnet.ibm.com>
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Cc: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
CVE-2016-3961
BugLink: https://bugs.launchpad.net/bugs/1571020
(cherry picked from commit 2531c8cf56a640cd7d17057df8484e570716a450)
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
---
 include/linux/hugetlb.h | 17 ++++++++---------
 1 file changed, 8 insertions(+), 9 deletions(-)
diff mbox

Patch

diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h
index 57f4e9368ec4..4367316ff4c6 100644
--- a/include/linux/hugetlb.h
+++ b/include/linux/hugetlb.h
@@ -404,15 +404,14 @@  static inline spinlock_t *huge_pte_lockptr(struct hstate *h,
 	return &mm->page_table_lock;
 }
 
-static inline bool hugepages_supported(void)
-{
-	/*
-	 * Some platform decide whether they support huge pages at boot
-	 * time. On these, such as powerpc, HPAGE_SHIFT is set to 0 when
-	 * there is no such support
-	 */
-	return HPAGE_SHIFT != 0;
-}
+#ifndef hugepages_supported
+/*
+ * Some platform decide whether they support huge pages at boot
+ * time. Some of them, such as powerpc, set HPAGE_SHIFT to 0
+ * when there is no such support
+ */
+#define hugepages_supported() (HPAGE_SHIFT != 0)
+#endif
 
 #else	/* CONFIG_HUGETLB_PAGE */
 struct hstate {};