DMARC-Filter: OpenDMARC Filter v1.3.2 mx1.redhat.com 92887BCD24
Date: Tue, 13 Jun 2017 16:06:20 +0200
From: Jiri Olsa <jolsa@redhat.com>
To: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Tan Xiaojun <tanxiaojun@huawei.com>, Ingo Molnar <mingo@kernel.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        Mark Rutland <mark.rutland@arm.com>, jolsa@kernel.org,
        Zhong Jiang <zhongjiang@huawei.com>,
        "linux-arm-kernel@lists.infradead.org" 
        <linux-arm-kernel@lists.infradead.org>,
        Laura Abbott <labbott@fedoraproject.org>
Subject: Re: [PATCH 0/2] arm64: fix crash when reading /proc/kcore
Message-ID: <20170613140620.GA10107@krava>
References: <20170608194139.9250-1-ard.biesheuvel@linaro.org>
 <593F4721.7000501@huawei.com>
 <CAKv+Gu_GqUPDjie0kqV32fs8ZobXe7T2KcdBmE3RuqSYaz6f1Q@mail.gmail.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <CAKv+Gu_GqUPDjie0kqV32fs8ZobXe7T2KcdBmE3RuqSYaz6f1Q@mail.gmail.com>
User-Agent: Mutt/1.8.0 (2017-02-23)
Sender: linux-kernel-owner@vger.kernel.org
Content-Length: 2013
Lines: 56

On Tue, Jun 13, 2017 at 09:17:49AM +0200, Ard Biesheuvel wrote:
> On 13 June 2017 at 04:00, Tan Xiaojun <tanxiaojun@huawei.com> wrote:
> > On 2017/6/9 3:41, Ard Biesheuvel wrote:
> >> This is a follow-up to patches from zhonjiang [0] and myself [1] that aim
> >> to solve a problem in the kcore code, which gets confused by the presence
> >> of block mappings in the vmalloc region.
> >>
> >> While fixing the crash is quite straight forward [2], we need to tweak
> >> the kcore code itself to ensure that it operates correctly on arm64.
> >> Fortunately, we can achieve this with two very simple changes:
> >>
> >> - replace a call to is_vmalloc_or_module_addr() in read_kcore() with a
> >>   comparison of the kclist type field (#1)
> >> - enable CONFIG_ARCH_PROC_KCORE_TEXT for arm64 (#2)
> >>
> >> [0] http://marc.info/?l=linux-mm&m=149632393629295&w=2
> >> [1] http://marc.info/?l=linux-mm&m=149685966530180&w=2
> >> [2] http://marc.info/?l=linux-mm&m=149694975123959&w=2
> >>
> >> Ard Biesheuvel (2):
> >>   fs/proc: kcore: use kcore_list type to check for vmalloc/module
> >>     address
> >>   arm64: mm: select CONFIG_ARCH_PROC_KCORE_TEXT
> >>
> >>  arch/arm64/Kconfig | 3 +++
> >>  fs/proc/kcore.c    | 2 +-
> >>  2 files changed, 4 insertions(+), 1 deletion(-)
> >>
> >
> > Reported-by: Tan Xiaojun <tanxiaojun@huawei.com>
> > Tested-by: Tan Xiaojun <tanxiaojun@huawei.com>
> >
> > Thank you for working on this problem which I reported two months ago.
> >
> > https://patchwork.kernel.org/patch/9687319/
> >
> > I tested, and it really solved the problem in Hisilicon D02/D03/D05.
> >
> 
> Thank you.
> 
> fs/proc/kcore.c does not have a maintainer according to
> get_maintainer.pl but it would be nice if we could get an ack on patch
> #1 from someone who is not a usual ARM suspect.
> 
> Patch #1 is here:
> http://marc.info/?l=linux-kernel&m=149695092424288&w=2
> 
> Ingo, Andrew, Jiri, any objections?

hi,
pretty straightforward.. looks ok to me

Reviewed-by: Jiri Olsa <jolsa@kernel.org>

jirka