linux-kernel - [PATCH v12 20/29] HMM: handle HMM device page table entry on mirror page table fault and update.

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: <1457469802-11850-21-git-send-email-jglisse@redhat.com>
Date:	Tue,  8 Mar 2016 15:43:13 -0500
From:	Jérôme Glisse <jglisse@...hat.com>
To:	akpm@...ux-foundation.org, <linux-kernel@...r.kernel.org>,
	linux-mm@...ck.org
Cc:	Linus Torvalds <torvalds@...ux-foundation.org>, <joro@...tes.org>,
	Mel Gorman <mgorman@...e.de>, "H. Peter Anvin" <hpa@...or.com>,
	Peter Zijlstra <peterz@...radead.org>,
	Andrea Arcangeli <aarcange@...hat.com>,
	Johannes Weiner <jweiner@...hat.com>,
	Larry Woodman <lwoodman@...hat.com>,
	Rik van Riel <riel@...hat.com>,
	Dave Airlie <airlied@...hat.com>,
	Brendan Conoboy <blc@...hat.com>,
	Joe Donohue <jdonohue@...hat.com>,
	Christophe Harle <charle@...dia.com>,
	Duncan Poole <dpoole@...dia.com>,
	Sherry Cheung <SCheung@...dia.com>,
	Subhash Gutti <sgutti@...dia.com>,
	John Hubbard <jhubbard@...dia.com>,
	Mark Hairgrove <mhairgrove@...dia.com>,
	Lucien Dunning <ldunning@...dia.com>,
	Cameron Buschardt <cabuschardt@...dia.com>,
	Arvind Gopalakrishnan <arvindg@...dia.com>,
	Haggai Eran <haggaie@...lanox.com>,
	Shachar Raindel <raindel@...lanox.com>,
	Liran Liss <liranl@...lanox.com>,
	Roland Dreier <roland@...estorage.com>,
	Ben Sander <ben.sander@....com>,
	Greg Stoner <Greg.Stoner@....com>,
	John Bridgman <John.Bridgman@....com>,
	Michael Mantor <Michael.Mantor@....com>,
	Paul Blinzer <Paul.Blinzer@....com>,
	Leonid Shamis <Leonid.Shamis@....com>,
	Laurent Morichetti <Laurent.Morichetti@....com>,
	Alexander Deucher <Alexander.Deucher@....com>,
	Jérôme Glisse <jglisse@...hat.com>
Subject: [PATCH v12 20/29] HMM: handle HMM device page table entry on mirror page table fault and update.

When faulting or updating the device page table properly handle the case of
device memory entry.

Signed-off-by: Jérôme Glisse <jglisse@...hat.com>
---
 mm/hmm.c | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/mm/hmm.c b/mm/hmm.c
index a5706d2..9455443 100644
--- a/mm/hmm.c
+++ b/mm/hmm.c
@@ -616,6 +616,13 @@ static void hmm_mirror_update_pte(struct hmm_mirror *mirror,
 		goto out;
 	}
 
+	if (hmm_pte_test_valid_dev(hmm_pte)) {
+		*hmm_pte &= event->pte_mask;
+		if (!hmm_pte_test_valid_dev(hmm_pte))
+			hmm_pt_iter_directory_unref(iter);
+		return;
+	}
+
 	if (!hmm_pte_test_valid_dma(hmm_pte))
 		return;
 
@@ -808,6 +815,12 @@ static int hmm_mirror_fault_pmd(pmd_t *pmdp,
 		ptep = pte_offset_map(pmdp, start);
 		hmm_pt_iter_directory_lock(iter);
 		do {
+			if (hmm_pte_test_valid_dev(&hmm_pte[i])) {
+				if (write)
+					hmm_pte_set_write(&hmm_pte[i]);
+				continue;
+			}
+
 			if (!pte_present(*ptep) ||
 			    (write && !pte_write(*ptep)) ||
 			    pte_protnone(*ptep)) {
-- 
2.4.3