Re: user malloc from kernel

From: Brian O'Shea (b_oshea_at_yahoo.com)
Date: 09/30/03

  • Next message: Sergey Babkin: "Re: has anyone installed 5.1 from a SCSI CD?" 
    Date: Mon, 29 Sep 2003 17:04:05 -0700 (PDT)
To: Peter Pentchev <roam@ringlet.net>, Pawel Jakub Dawidek <nick@garage.freebsd.pl>

    --- Peter Pentchev <roam@ringlet.net> wrote:
    > > Here you got sample kernel module which do this:
    > >
    > > http://garage.freebsd.pl/usmalloc.tgz
    > > http://garage.freebsd.pl/usmalloc.README
    >
    > Errrr... but won't this interfere *badly* with userland programs
    > which attempt to allocate memory after making the syscall in question?

    Couldn't the user library interface to this new system call just
    malloc() the memory first in the process, and then pass the pointer
    and size to the kernel via the system call interface? This would
    ensure that malloc() doesn't touch the desired range of memory until
    it is freed by the user. You'd just have to be careful not to free
    it until the kernel is done with it.

    -brian

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  • Next message: Sergey Babkin: "Re: has anyone installed 5.1 from a SCSI CD?"

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