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    SubjectRe: [PATCH v3] initramfs: finish fput() before accessing any binary from initramfs
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    On 02/02/17 00:12, Andrew Morton wrote:
    > On Wed, 1 Feb 2017 19:35:40 +0530 Lokesh Vutla <lokeshvutla@ti.com> wrote:
    >
    >> commit 4a9d4b024a31 ("switch fput to task_work_add") implements a
    >> schedule_work() for completing fput(), but did not guarantee calling
    >> __fput() after unpacking initramfs. Because of this, there is a
    >> possibility that during boot a driver can see ETXTBSY when it tries
    >> to load a binary from initramfs as fput() is still pending on that
    >> binary. This patch makes sure that fput() is completed after unpacking
    >> initramfs and removes the call to flush_delayed_fput() in kernel_init()
    >> which happens very late after unpacking initramfs.
    >
    > There's not really enough info here for others to be able to decide
    > which kernel versions need the fix. How serious is the bug? Given
    > that it's been there for 4 years, I assume "not very"?

    I think the issue only surfaces with certain timing conditions, and for
    some reason it has been masked for at least us until we noticed this
    with 4.9-lts kernel. The same issue was not detected with earlier
    4.4-lts kernel.

    -Tero

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