From: Jason Gunthorpe <jgg@ziepe.ca>
To: Pavel Tatashin <pasha.tatashin@soleen.com>
Cc: LKML <linux-kernel@vger.kernel.org>,
linux-mm <linux-mm@kvack.org>,
Andrew Morton <akpm@linux-foundation.org>,
Vlastimil Babka <vbabka@suse.cz>, Michal Hocko <mhocko@suse.com>,
David Hildenbrand <david@redhat.com>,
Oscar Salvador <osalvador@suse.de>,
Dan Williams <dan.j.williams@intel.com>,
Sasha Levin <sashal@kernel.org>,
Tyler Hicks <tyhicks@linux.microsoft.com>,
Joonsoo Kim <iamjoonsoo.kim@lge.com>,
mike.kravetz@oracle.com, Steven Rostedt <rostedt@goodmis.org>,
Ingo Molnar <mingo@redhat.com>,
Peter Zijlstra <peterz@infradead.org>,
Mel Gorman <mgorman@suse.de>,
Matthew Wilcox <willy@infradead.org>,
David Rientjes <rientjes@google.com>,
John Hubbard <jhubbard@nvidia.com>,
Linux Doc Mailing List <linux-doc@vger.kernel.org>,
Ira Weiny <ira.weiny@intel.com>,
linux-kselftest@vger.kernel.org
Subject: Re: [PATCH v5 08/14] mm/gup: do not allow zero page for pinned pages
Date: Tue, 19 Jan 2021 19:35:21 -0400 [thread overview]
Message-ID: <20210119233521.GE4605@ziepe.ca> (raw)
In-Reply-To: <CA+CK2bDGDR9B=n5d4Dz6my6kKyFF=6y79HJt-k-SCpLhF1fUQQ@mail.gmail.com>
On Tue, Jan 19, 2021 at 03:14:04PM -0500, Pavel Tatashin wrote:
> I was thinking about a use case where userland would pin an address
> without FOLL_WRITE, because the PTE for that address is not going to
> be writable, but some device via DMA will write to it.
That would be a serious bug in the get_user_pages caller to write to a
page without using FOLL_WRITE
Jason
next prev parent reply other threads:[~2021-01-19 23:35 UTC|newest]
Thread overview: 25+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-01-19 4:39 [PATCH v5 00/14] prohibit pinning pages in ZONE_MOVABLE Pavel Tatashin
2021-01-19 4:39 ` [PATCH v5 01/14] mm/gup: don't pin migrated cma pages in movable zone Pavel Tatashin
2021-01-19 4:39 ` [PATCH v5 02/14] mm/gup: check every subpage of a compound page during isolation Pavel Tatashin
2021-01-19 18:05 ` Jason Gunthorpe
2021-01-19 4:39 ` [PATCH v5 03/14] mm/gup: return an error on migration failure Pavel Tatashin
2021-01-19 18:28 ` Jason Gunthorpe
2021-01-19 4:39 ` [PATCH v5 04/14] mm/gup: check for isolation errors Pavel Tatashin
2021-01-19 18:22 ` Jason Gunthorpe
2021-01-19 18:27 ` Pavel Tatashin
2021-01-19 4:39 ` [PATCH v5 05/14] mm cma: rename PF_MEMALLOC_NOCMA to PF_MEMALLOC_PIN Pavel Tatashin
2021-01-19 4:39 ` [PATCH v5 06/14] mm: apply per-task gfp constraints in fast path Pavel Tatashin
2021-01-19 4:39 ` [PATCH v5 07/14] mm: honor PF_MEMALLOC_PIN for all movable pages Pavel Tatashin
2021-01-19 4:39 ` [PATCH v5 08/14] mm/gup: do not allow zero page for pinned pages Pavel Tatashin
2021-01-19 18:30 ` Jason Gunthorpe
2021-01-19 18:34 ` Pavel Tatashin
2021-01-19 18:47 ` Jason Gunthorpe
2021-01-19 20:14 ` Pavel Tatashin
2021-01-19 20:48 ` Pavel Tatashin
2021-01-19 23:35 ` Jason Gunthorpe [this message]
2021-01-19 4:39 ` [PATCH v5 09/14] mm/gup: migrate pinned pages out of movable zone Pavel Tatashin
2021-01-19 4:39 ` [PATCH v5 10/14] memory-hotplug.rst: add a note about ZONE_MOVABLE and page pinning Pavel Tatashin
2021-01-19 4:39 ` [PATCH v5 11/14] mm/gup: change index type to long as it counts pages Pavel Tatashin
2021-01-19 4:39 ` [PATCH v5 12/14] mm/gup: longterm pin migration cleaup Pavel Tatashin
2021-01-19 4:39 ` [PATCH v5 13/14] selftests/vm: test flag is broken Pavel Tatashin
2021-01-19 4:39 ` [PATCH v5 14/14] selftests/vm: test faulting in kernel, and verify pinnable pages Pavel Tatashin
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