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    SubjectRe: [PATCH] /dev/mem: Bail out upon SIGKILL when reading memory.
    On Sat, Aug 24, 2019 at 10:50 PM Tetsuo Handa
    <penguin-kernel@i-love.sakura.ne.jp> wrote:
    >
    > @@ -142,7 +144,7 @@ static ssize_t read_mem(struct file *file, char __user *buf,
    > sz = size_inside_page(p, count);
    > cond_resched();
    > err = -EINTR;
    > - if (fatal_signal_pending(current))
    > + if (signal_pending(current))
    > goto failed;
    >
    > err = -EPERM;

    So from a "likelihood of breaking" standpoint, I'd really like to make
    sure that the "signal_pending()" checks come at the *end* of the loop.

    That way, if somebody is doing a 4-byte read from MMIO, he'll never see -EINTR.

    I'm specifically thinking of tools like user-space 'lspci' etc, which
    I wouldn't be surprised could happen.

    Also, just in case things break, I do agree with Ingo that this should
    be split up into several patches.

    Linus

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