From: Michal Hocko <mhocko@kernel.org>
To: Pavel Tatashin <pasha.tatashin@oracle.com>
Cc: steven.sistare@oracle.com, daniel.m.jordan@oracle.com,
akpm@linux-foundation.org, mgorman@techsingularity.net,
linux-mm@kvack.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH v1 1/1] mm: buddy page accessed before initialized
Date: Fri, 3 Nov 2017 09:59:58 +0100 [thread overview]
Message-ID: <20171103085958.pewhlyvkr5oa2fgf@dhcp22.suse.cz> (raw)
In-Reply-To: <8b3bb799-818b-b6b6-7c6b-9eee709decb7@oracle.com>
On Thu 02-11-17 12:10:39, Pavel Tatashin wrote:
> > >
> > > Yes, but as I said, unfortunately memset(1) with CONFIG_VM_DEBUG does not
> > > catch this case. So, when CONFIG_VM_DEBUG is enabled kexec reboots without
> > > issues.
> >
> > Can we make the init pattern to catch this?
>
> Unfortunately, that is not easy: memset() gives us only one byte to play
> with, and if we use something else that will make CONFIG_VM_DEBUG
> unacceptably slow.
Why cannot we do something similar to the optimized struct page
initialization and write 8B at the time and fill up the size unaligned
chunk in 1B?
--
Michal Hocko
SUSE Labs
next prev parent reply other threads:[~2017-11-03 9:00 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-10-31 15:50 [PATCH v1 0/1] buddy page accessed before initialized Pavel Tatashin
2017-10-31 15:50 ` [PATCH v1 1/1] mm: " Pavel Tatashin
2017-11-02 13:32 ` Michal Hocko
2017-11-02 13:39 ` Pavel Tatashin
2017-11-02 13:54 ` Michal Hocko
2017-11-02 14:00 ` Pavel Tatashin
2017-11-02 14:08 ` Michal Hocko
2017-11-02 14:16 ` Pavel Tatashin
2017-11-02 14:27 ` Michal Hocko
2017-11-02 16:10 ` Pavel Tatashin
2017-11-03 8:59 ` Michal Hocko [this message]
2017-11-03 14:17 ` Pavel Tatashin
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