Re: [RFC PATCH] linux-user: un-parent OBJECT(cpu) when closing thread

[Laurent Vivier]

Le 10/06/2022 à 16:38, Alex Bennée a écrit :

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.ben...@linaro.org>
---
  linux-user/syscall.c | 2 +-
  1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/linux-user/syscall.c b/linux-user/syscall.c
index f55cdebee5..c413d32311 100644
--- a/linux-user/syscall.c
+++ b/linux-user/syscall.c
@@ -8566,7 +8566,7 @@ static abi_long do_syscall1(CPUArchState *cpu_env, int 
num, abi_long arg1,
          if (CPU_NEXT(first_cpu)) {
              TaskState *ts = cpu->opaque;

- object_property_set_bool(OBJECT(cpu), "realized", false, NULL);

+            object_unparent(OBJECT(cpu));
              object_unref(OBJECT(cpu));
              /*
               * At this point the CPU should be unrealized and removed

Applied to my linux-user-for-7.1 branch.

Thanks,
Laurent