From: "H. Peter Anvin" <hpa@zytor.com>
To: Andy Lutomirski <luto@amacapital.net>
Cc: Pavel Emelyanov <xemul@parallels.com>,
aarcange@redhat.com, ak@linux.intel.com,
Stefani Seibold <stefani@seibold.net>,
x86@kernel.org, linux-kernel@vger.kernel.org, criu@openvz.org,
mingo@redhat.com, john.stultz@linaro.org, tglx@linutronix.de
Subject: Re: [CRIU] [PATCH] Add VDSO time function support for x86 32-bit kernel
Date: Fri, 14 Dec 2012 10:47:53 -0800 [thread overview]
Message-ID: <50CB7459.7010107@zytor.com> (raw)
In-Reply-To: <CALCETrWazriQVbQPc8u+KFyNUaa=kJUc=jdh9w7z6rS+kWEX1w@mail.gmail.com>
On 12/14/2012 10:44 AM, Andy Lutomirski wrote:
>>
>> mremap() should work. At the same time, the code itself is not going to
>> have any stability guarantees between kernel versions -- it obviously
>> cannot.
>
> We could guarantee that the symbols in the vdso resolve to particular
> offsets within the vdso. (Yes, this is ugly.)
>
> Does criu support checkpointing with one version of a shared library
> and restoring with another? If there are no textrels (or whatever the
> relocation type that actually modifies text as opposed to just the plt
> or got) then, in principle, it should be doable. Otherwise some
> kernel help will be needed to checkpoint reliably on one kernel and
> restore somewhere else.
>
> (This isn't a regression -- it's already broken.)
>
The real issue is that happens if the process is checkpointed while
inside the vdso and now eip/rip or a stack frame points into the vdso.
This is not impossible or even unlikely, especially on 32 bits it is
downright likely.
-hpa
next prev parent reply other threads:[~2012-12-14 18:48 UTC|newest]
Thread overview: 41+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-12-12 20:19 [PATCH] Add VDSO time function support for x86 32-bit kernel stefani
2012-12-12 23:34 ` H. Peter Anvin
2012-12-13 5:53 ` Stefani Seibold
2012-12-13 6:10 ` H. Peter Anvin
2012-12-13 6:14 ` H. Peter Anvin
2012-12-13 6:17 ` Stefani Seibold
2012-12-13 6:47 ` H. Peter Anvin
2012-12-13 7:17 ` Stefani Seibold
2012-12-13 19:32 ` Andy Lutomirski
2012-12-14 0:09 ` H. Peter Anvin
2012-12-14 0:20 ` Andy Lutomirski
2012-12-14 0:36 ` H. Peter Anvin
2012-12-14 1:32 ` H. Peter Anvin
2012-12-14 1:42 ` Andy Lutomirski
2012-12-14 1:49 ` H. Peter Anvin
2012-12-14 2:11 ` Andy Lutomirski
2012-12-14 2:18 ` H. Peter Anvin
2012-12-14 2:20 ` Andy Lutomirski
2012-12-14 8:34 ` [CRIU] " Pavel Emelyanov
2012-12-14 18:35 ` H. Peter Anvin
2012-12-14 18:44 ` Andy Lutomirski
2012-12-14 18:47 ` H. Peter Anvin [this message]
2012-12-14 20:12 ` Cyrill Gorcunov
2012-12-14 21:08 ` H. Peter Anvin
2012-12-14 21:20 ` Cyrill Gorcunov
2012-12-14 21:21 ` H. Peter Anvin
2012-12-14 21:27 ` Andy Lutomirski
2012-12-14 22:00 ` H. Peter Anvin
2012-12-14 22:25 ` Cyrill Gorcunov
2012-12-14 22:27 ` H. Peter Anvin
2012-12-14 22:43 ` Cyrill Gorcunov
2012-12-14 22:48 ` H. Peter Anvin
2012-12-14 23:48 ` John Stultz
2012-12-14 23:55 ` H. Peter Anvin
2012-12-17 9:05 ` Pavel Emelyanov
[not found] ` <fb2e871b-3e2a-4e96-9eb9-cb2dd4f66eaa@email.android! .com>
2012-12-17 15:21 ` H. Peter Anvin
2012-12-17 18:56 ` Pavel Emelyanov
2012-12-17 18:57 ` H. Peter Anvin
2012-12-14 22:46 ` H. Peter Anvin
2012-12-14 23:09 ` Stefani Seibold
2012-12-14 23:29 ` H. Peter Anvin
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