lkml.org 
[lkml]   [2010]   [Mar]   [25]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    Date
    From
    SubjectRe: [C/R ARM][PATCH 3/3] c/r: ARM implementation of checkpoint/restart
    Christoffer Dall wrote:
    > > That doesn't indicate what ISA version the system is running on, or even
    > > if the ABI is compatible (we have two ABIs - OABI and EABI).
    >
    > That's why I checkpointed CONFIG_OABI_COMPAT, but I realize that it's
    > not sufficient.
    >
    > How about checkpointing CONFIG_AEABI and CONFIG_OABI_COMPAT and making
    > sure that we either restore to the same setting of the two or restore
    > to CONFIG_OABI_COMPAT=y?

    With CONFIG_OABI_COMPAT enabled, each process can be in either
    personality: OABI or EABI. Checkpointing will need to remember which
    one.

    With CONFIG_OABI_COMPAT disabled, it'll be fixed at one or the other,
    but there's no reason why a process should not be moved between
    kernels with different values of CONFIG_OABI_COMPAT, so long as the
    OABI or EABI personality is supported by the destination kernel.

    In other words, CONFIG_OABI_COMPAT shouldn't be in the checkpoint
    state at all - only the per-process personalities should be.

    > >> We checkpoint whether the system is running with CONFIG_MMU or not and
    > >> require the same configuration for the system on which we restore the
    > >> process. It might be possible to allow something more fine-grained,
    > >> if it's worth the energy. Input on this item is also very welcome,
    > >> specifically from someone who knows the exact meaning of the end_brk
    > >> field.
    > >
    > > Processes which run on MMU and non-MMU CPUs are unlikely to be
    > > interchangable - the run time environments are quite different.  I
    > > think this is a sane check.
    > >
    > thanks.

    It's possible in principle to run many non-MMU binaries on MMU
    kernels, but I've never heard of anyone doing it.

    -- Jamie

    --
    To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
    the body of a message to majordomo@vger.kernel.org
    More majordomo info at http://vger.kernel.org/majordomo-info.html
    Please read the FAQ at http://www.tux.org/lkml/

    \
     
     \ /
      Last update: 2010-03-26 03:51    [W:0.026 / U:0.108 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site