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    SubjectRe: [PATCH 1/3] uprobes/core: Remove redundant lock_page/unlock_page
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    On Thu, 2012-05-31 at 20:37 +0530, Srikar Dronamraju wrote:
    > * Peter Zijlstra <peterz@infradead.org> [2012-05-31 13:58:38]:
    >
    > > On Thu, 2012-05-31 at 17:16 +0530, Srikar Dronamraju wrote:
    > > > From: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
    > > >
    > > > No need to lock the page when copying the opcode in read_opcode().
    > >
    > > It would be good if the changelog said _why_ this is so :-)
    >
    > In read_opcode(), we have the reference for the page and we only are reading
    > from the the page. i.e we are neither modifying the page contents, not
    > the page attributes.

    Fair enough, so put that in the changelog. The changelog should explain
    things, not raise questions.

    > Existing kernel code has enough examples where we read the contents
    > of the page without taking the page lock.

    Yes, but that doesn't tell us this site is ok, doing it because others
    do isn't an argument.

    > Further this was discussed here too https://lkml.org/lkml/2012/4/17/361.

    That wasn't a discussion, that was two people saying they don't know.


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