From: Miles Chen <miles.chen@mediatek.com>
To: Catalin Marinas <catalin.marinas@arm.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>,
Andrew Morton <akpm@linux-foundation.org>,
<linux-kernel@vger.kernel.org>, <linux-fsdevel@vger.kernel.org>,
<linux-mediatek@lists.infradead.org>, <wsd_upstream@mediatek.com>,
Andrey Konovalov <andreyknvl@google.com>,
Alexander Potapenko <glider@google.com>,
Vincenzo Frascino <vincenzo.frascino@arm.com>,
Andrey Ryabinin <aryabinin@virtuozzo.com>,
Dmitry Vyukov <dvyukov@google.com>,
Marco Elver <elver@google.com>, "Will Deacon" <will@kernel.org>,
"Eric W . Biederman" <ebiederm@xmission.com>,
Song Bao Hua <song.bao.hua@hisilicon.com>,
<stable@vger.kernel.org>
Subject: Re: [PATCH v2] proc: use untagged_addr() for pagemap_read addresses
Date: Fri, 4 Dec 2020 09:34:08 +0800 [thread overview]
Message-ID: <1607045648.22275.7.camel@mtkswgap22> (raw)
In-Reply-To: <20201203113020.GE2224@gaia>
On Thu, 2020-12-03 at 11:30 +0000, Catalin Marinas wrote:
> On Fri, Nov 27, 2020 at 01:07:38PM +0800, Miles Chen wrote:
> > Cc: Will Deacon <will.deacon@arm.com>
>
> That should be will@kernel.org.
ok, I will fix it and submit v3
>
> > diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c
> > index 217aa2705d5d..92b277388f05 100644
> > --- a/fs/proc/task_mmu.c
> > +++ b/fs/proc/task_mmu.c
> > @@ -1599,11 +1599,15 @@ static ssize_t pagemap_read(struct file *file, char __user *buf,
> >
> > src = *ppos;
> > svpfn = src / PM_ENTRY_BYTES;
> > - start_vaddr = svpfn << PAGE_SHIFT;
> > end_vaddr = mm->task_size;
> >
> > /* watch out for wraparound */
> > - if (svpfn > mm->task_size >> PAGE_SHIFT)
> > + start_vaddr = end_vaddr;
> > + if (svpfn < (ULONG_MAX >> PAGE_SHIFT))
>
> Does this need to be strict less-than? I think a less-than or equal
> would work better.
Thanks, I will fix it and submit v3.
>
> > + start_vaddr = untagged_addr(svpfn << PAGE_SHIFT);
> > +
> > + /* Ensure the address is inside the task */
> > + if (start_vaddr > mm->task_size)
> > start_vaddr = end_vaddr;
>
> Otherwise the logic looks fine to me. With the above:
>
> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
next prev parent reply other threads:[~2020-12-04 1:35 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-11-27 5:07 [PATCH v2] proc: use untagged_addr() for pagemap_read addresses Miles Chen
2020-12-03 11:30 ` Catalin Marinas
2020-12-04 1:34 ` Miles Chen [this message]
2020-12-03 11:45 ` Vincenzo Frascino
2020-12-04 1:33 ` Miles Chen
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=1607045648.22275.7.camel@mtkswgap22 \
--to=miles.chen@mediatek.com \
--cc=adobriyan@gmail.com \
--cc=akpm@linux-foundation.org \
--cc=andreyknvl@google.com \
--cc=aryabinin@virtuozzo.com \
--cc=catalin.marinas@arm.com \
--cc=dvyukov@google.com \
--cc=ebiederm@xmission.com \
--cc=elver@google.com \
--cc=glider@google.com \
--cc=linux-fsdevel@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mediatek@lists.infradead.org \
--cc=song.bao.hua@hisilicon.com \
--cc=stable@vger.kernel.org \
--cc=vincenzo.frascino@arm.com \
--cc=will@kernel.org \
--cc=wsd_upstream@mediatek.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).