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    SubjectRe: [syzbot] BUG: sleeping function called from invalid context in __might_resched
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    > On Tuesday, November 16, 2021 9:53:53 AM CET Fabio M. De Francesco wrote:
    >> On Tuesday, November 16, 2021 9:09:11 AM CET syzbot wrote:
    >> > Hello,
    >> >
    >> > syzbot has tested the proposed patch but the reproducer is still
    > triggering
    >> an issue:
    >> > BUG: sleeping function called from invalid context in __might_resched
    >> > [...]
    >>
    >> The reproducer is still triggering an issue, but this time it looks like it
    >> is triggered by a different path of execution.
    >>
    >> The same invalid "in_interrupt()" test is also in con_flush_chars().
    >>
    >> Let's try to remove it too...
    >>
    >> My first idea would be to replace "if (in_interrupt())" with the same
    >> "preempt_count() || irqs_disabled()" I used in do_con_write(). However I
    >> noticed that both do_con_write() and con_flush_chars() are only called from
    >> inside con_write() (which, aside from calling those functions, does nothing
    >> else).
    >>
    >> So why not remove the if (in_interrupt()) from both them and use if
    >> (preempt_count() || irqs_disabled()) just once in con_write()?
    >>
    >> I think this should be the right solution, but I prefer to go one step at a
    >> time.
    >>
    >> Therefore, I'll (1) use the same (redundant, if it was used in con_write())
    >> test also in con_flush_chars(), (2) wait for Syzbot to confirm that it
    > fixes
    >> the bug, and (3) wait for maintainers review and suggestions about whether
    > or
    >> not moving those tests one level upper.
    >>
    >> #syz test:
    >> git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
    >>
    >> ---
    >> Fabio M. De Francesco
    >
    > Don't know exactly what happened, so let's retry the test...
    >
    > #syz test:

    want 2 args (repo, branch), got 1

    > git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git

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