Re: linux-user emulation hangs during fork

[Andreas Schwab]

6490d9aa62ef3cbbac2bf584fb0f3e737ab05e44 is the first bad commit
commit 6490d9aa62ef3cbbac2bf584fb0f3e737ab05e44
Author: Richard Henderson <richard.henderson@linaro.org>
Date:   Tue Jan 24 10:10:19 2023 -1000

    linux-user: un-parent OBJECT(cpu) when closing thread
    
    This reinstates commit 52f0c1607671293afcdb2acc2f83e9bccbfa74bb:
    
    While forcing the CPU to unrealize by hand does trigger the clean-up
    code we never fully free resources because refcount never reaches
    zero. This is because QOM automatically added objects without an
    explicit parent to /unattached/, incrementing the refcount.
    
    Instead of manually triggering unrealization just unparent the object
    and let the device machinery deal with that for us.
    
    Resolves: https://gitlab.com/qemu-project/qemu/-/issues/866
    Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
    Reviewed-by: Laurent Vivier <laurent@vivier.eu>
    Message-Id: <20220811151413.3350684-2-alex.bennee@linaro.org>
    
    The original patch tickled a problem in target/arm, and was reverted.
    But that problem is fixed as of commit 3b07a936d3bf.
    
    Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
    Message-Id: <20230124201019.3935934-1-richard.henderson@linaro.org>
    Signed-off-by: Laurent Vivier <laurent@vivier.eu>

 linux-user/syscall.c | 13 +++++++------
 1 file changed, 7 insertions(+), 6 deletions(-)

-- 
Andreas Schwab, SUSE Labs, schwab@suse.de
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"And now for something completely different."