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From: Florian Weimer <fweimer@redhat.com>
To: linux-mm@kvack.org, linux-api@vger.kernel.org, libc-alpha@sourceware.org
Subject: Are vDSO addresses special?
Date: Thu, 11 Feb 2021 10:58:20 +0100	[thread overview]
Message-ID: <87zh0bq62r.fsf@oldenburg.str.redhat.com> (raw)

In glibc, we have some code that copies the DT_SONAME string of the
kernel vDSO into the heap, commented this way:

             /* Work around a kernel problem.  The kernel cannot handle
                addresses in the vsyscall DSO pages in writev() calls.  */

Is this really a problem anymore?  vDSO addresses are ordinary userspace
addresses, I think.  (The vsyscall stuff is very different, of course,
and maybe the vDSO started out the same way.)

We only care about Linux 3.2 or later in glibc.

Thanks,
Florian
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             reply	other threads:[~2021-02-11 10:03 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-02-11  9:58 Florian Weimer [this message]
2021-02-11 16:10 ` Are vDSO addresses special? Andy Lutomirski
2021-02-12 17:29   ` Florian Weimer

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