linux-kernel - [PATCH 2/2] mm/hugetlb: pass correct order_per_bit to cma_declare_contiguous

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: Thu,  4 Apr 2024 16:25:15 +0000
From: Frank van der Linden <fvdl@...gle.com>
To: linux-mm@...ck.org, muchun.song@...ux.dev, akpm@...ux-foundation.org
Cc: linux-kernel@...r.kernel.org, Frank van der Linden <fvdl@...gle.com>, 
	Roman Gushchin <roman.gushchin@...ux.dev>
Subject: [PATCH 2/2] mm/hugetlb: pass correct order_per_bit to cma_declare_contiguous_nid

The hugetlb_cma code passes 0 in the order_per_bit argument to
cma_declare_contiguous_nid (the alignment, computed using the
page order, is correctly passed in).

This causes a bit in the cma allocation bitmap to always represent
a 4k page, making the bitmaps potentially very large, and slower.

So, correctly pass in the order instead.

Signed-off-by: Frank van der Linden <fvdl@...gle.com>
Cc: Roman Gushchin <roman.gushchin@...ux.dev>
Fixes: cf11e85fc08c ("mm: hugetlb: optionally allocate gigantic hugepages using cma")
---
 mm/hugetlb.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 23ef240ba48a..6dc62d8b2a3a 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -7873,9 +7873,9 @@ void __init hugetlb_cma_reserve(int order)
 		 * huge page demotion.
 		 */
 		res = cma_declare_contiguous_nid(0, size, 0,
-						PAGE_SIZE << HUGETLB_PAGE_ORDER,
-						 0, false, name,
-						 &hugetlb_cma[nid], nid);
+					PAGE_SIZE << HUGETLB_PAGE_ORDER,
+					HUGETLB_PAGE_ORDER, false, name,
+					&hugetlb_cma[nid], nid);
 		if (res) {
 			pr_warn("hugetlb_cma: reservation failed: err %d, node %d",
 				res, nid);
-- 
2.44.0.478.gd926399ef9-goog