From: Dan Williams <dan.j.williams@intel.com>
To: "Darrick J. Wong" <darrick.wong@oracle.com>
Cc: Matthew Wilcox <willy@infradead.org>,
Ira Weiny <ira.weiny@intel.com>,
Thomas Gleixner <tglx@linutronix.de>,
Andrew Morton <akpm@linux-foundation.org>,
Dave Hansen <dave.hansen@intel.com>,
Christoph Hellwig <hch@infradead.org>,
Al Viro <viro@zeniv.linux.org.uk>,
Eric Biggers <ebiggers@kernel.org>,
Joonas Lahtinen <joonas.lahtinen@linux.intel.com>,
Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
linux-fsdevel <linux-fsdevel@vger.kernel.org>
Subject: Re: [PATCH V2 2/2] mm/highmem: Lift memcpy_[to|from]_page to core
Date: Tue, 8 Dec 2020 15:40:52 -0800 [thread overview]
Message-ID: <CAPcyv4jEmdfAz8foEUtDw4GEm2-+7J-4GULZ=6tCD+9K5CFzRw@mail.gmail.com> (raw)
In-Reply-To: <20201208224555.GA605321@magnolia>
On Tue, Dec 8, 2020 at 2:49 PM Darrick J. Wong <darrick.wong@oracle.com> wrote:
[..]
> > So what's your preferred poison?
> >
> > 1. Corrupt random data in whatever's been mapped into the next page (which
> > is what the helpers currently do)
>
> Please no.
My assertion is that the kernel can't know it's corruption, it can
only know that the driver is abusing the API. So over-copy and WARN
seems better than violently regress by crashing what might have been
working silently before.
next prev parent reply other threads:[~2020-12-08 23:41 UTC|newest]
Thread overview: 24+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-12-07 22:57 [PATCH V2 0/2] Lift memcpy_[to|from]_page to core ira.weiny
2020-12-07 22:57 ` [PATCH V2 1/2] mm/highmem: Remove deprecated kmap_atomic ira.weiny
2020-12-07 22:57 ` [PATCH V2 2/2] mm/highmem: Lift memcpy_[to|from]_page to core ira.weiny
2020-12-07 23:26 ` Matthew Wilcox
2020-12-07 23:34 ` Dan Williams
2020-12-07 23:40 ` Matthew Wilcox
2020-12-07 23:49 ` Dan Williams
2020-12-08 21:32 ` Ira Weiny
2020-12-08 21:50 ` Matthew Wilcox
2020-12-08 22:23 ` Dan Williams
2020-12-08 22:32 ` Matthew Wilcox
2020-12-08 22:45 ` Darrick J. Wong
2020-12-08 22:54 ` Matthew Wilcox
2020-12-08 23:40 ` Dan Williams [this message]
2020-12-09 2:22 ` Ira Weiny
2020-12-09 4:03 ` Matthew Wilcox
2020-12-09 19:47 ` Dan Williams
2020-12-09 20:14 ` Matthew Wilcox
2020-12-09 20:19 ` Dan Williams
2020-12-10 5:35 ` Ira Weiny
2020-12-08 22:21 ` Dan Williams
2020-12-08 12:23 ` Matthew Wilcox
2020-12-08 16:38 ` Ira Weiny
2020-12-08 16:40 ` Matthew Wilcox
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