From: Linus Torvalds <torvalds@linux-foundation.org>
To: Andrew Lutomirski <luto@mit.edu>
Cc: Ingo Molnar <mingo@elte.hu>,
richard -rw- weinberger <richard.weinberger@gmail.com>,
Adrian Bunk <bunk@stusta.de>,
"H. Peter Anvin" <hpa@linux.intel.com>,
Thomas Gleixner <tglx@linutronix.de>,
Ingo Molnar <mingo@redhat.com>,
x86@kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [RFC] fixing the UML failure root cause
Date: Thu, 13 Oct 2011 18:19:16 +1200 [thread overview]
Message-ID: <CA+55aFyMXgzywjXCtS1a5F-BDu_XP4ecg3Tw7zLuawZs0QNYaw@mail.gmail.com> (raw)
In-Reply-To: <4E947BC9.7040805@mit.edu>
On Wed, Oct 12, 2011 at 5:24 AM, Andrew Lutomirski <luto@mit.edu> wrote:
>
> So here's a different approach. It's not perfect: it always blames
> SEGV_MAPERR instead of SEGV_ACCERR. I implemented it for vgettimeofday
> but not the other two vsyscalls.
>
> What do you think of this approach? If it seems good, I'll finish the
> patch and submit it.
I think the approach is valid, but you should *not* do this as some
kind of crazy byte-by-byte copy_to_user() emulation.
Do the "copy tz to user mode" as individual "put_user()" calls for
tv_sec/tv_usec/timezone. IOW, there are three words being written to
user mode, not "two memcpy's".
Other than that, there doesn't seem to be anything wrong.
Linus
next prev parent reply other threads:[~2011-10-13 6:19 UTC|newest]
Thread overview: 47+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-10-03 9:08 [3.1 patch] x86: default to vsyscall=native Adrian Bunk
2011-10-03 13:04 ` Andrew Lutomirski
2011-10-03 17:33 ` Adrian Bunk
2011-10-03 18:06 ` Andrew Lutomirski
2011-10-03 18:41 ` Adrian Bunk
2011-10-05 22:13 ` Andrew Lutomirski
2011-10-05 22:22 ` richard -rw- weinberger
2011-10-05 22:30 ` Adrian Bunk
2011-10-05 22:41 ` richard -rw- weinberger
2011-10-05 22:46 ` Andrew Lutomirski
2011-10-05 23:36 ` Andrew Lutomirski
2011-10-06 3:06 ` Andrew Lutomirski
2011-10-06 12:12 ` richard -rw- weinberger
2011-10-06 15:37 ` richard -rw- weinberger
2011-10-06 18:16 ` Andrew Lutomirski
2011-10-06 18:34 ` Linus Torvalds
2011-10-07 0:48 ` Andrew Lutomirski
2011-10-10 11:19 ` richard -rw- weinberger
2011-10-10 11:48 ` Ingo Molnar
2011-10-10 15:31 ` Andrew Lutomirski
2011-10-11 6:22 ` Ingo Molnar
2011-10-11 17:24 ` [RFC] fixing the UML failure root cause Andrew Lutomirski
2011-10-13 6:19 ` Linus Torvalds [this message]
2011-10-13 8:40 ` Andrew Lutomirski
2011-10-14 4:46 ` Linus Torvalds
2011-10-14 6:30 ` Andrew Lutomirski
2011-10-14 20:10 ` Linus Torvalds
2011-10-21 21:01 ` [PATCH] x86-64: Set siginfo and context on vsyscall emulation faults Andy Lutomirski
2011-10-22 4:46 ` Linus Torvalds
2011-10-22 9:07 ` Andy Lutomirski
2011-11-08 0:33 ` [PATCH 0/2] Fix and re-enable vsyscall=emulate Andy Lutomirski
2011-11-08 0:33 ` [PATCH 1/2] x86-64: Set siginfo and context on vsyscall emulation faults Andy Lutomirski
2011-12-05 13:23 ` [tip:x86/asm] " tip-bot for Andy Lutomirski
2011-11-08 0:33 ` [PATCH 2/2] x86: Default to vsyscall=emulate Andy Lutomirski
2011-12-05 13:24 ` [tip:x86/asm] " tip-bot for Andy Lutomirski
2011-12-02 22:47 ` [PATCH 0/2] Fix and re-enable vsyscall=emulate Andy Lutomirski
2011-12-05 11:18 ` H. Peter Anvin
2011-10-14 19:53 ` [RFC] fixing the UML failure root cause richard -rw- weinberger
2011-10-14 20:17 ` Andrew Lutomirski
2011-10-14 20:23 ` richard -rw- weinberger
2011-10-14 20:31 ` Andrew Lutomirski
2011-10-14 20:39 ` richard -rw- weinberger
2011-10-14 22:28 ` richard -rw- weinberger
2011-10-15 16:57 ` Ingo Molnar
2011-10-05 22:24 ` [3.1 patch] x86: default to vsyscall=native Adrian Bunk
2011-10-03 13:19 ` richard -rw- weinberger
2011-10-03 17:46 ` Adrian Bunk
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