On 18/8/26 12:30, Paolo Bonzini wrote:
On Tue, Aug 18, 2026 at 11:24 AM Philippe Mathieu-Daudé
<[email protected]> wrote:
Your patch is correct because, even if cpu_thread_is_idle() sees cpu-
>halted == false, the flag could become true during
process_queued_cpu_work() because it releases the BQL.
However, I think the better fix is to remove the return code, and check
cpu->halted in kvm_cpu_exec().
Looking at it, even better would be to move *process_async_events()
from inner loop to outer loop for all accelerators. For HW accels it
seems quite trivial; for TCG I need to figure if it is safe to call
icount_prepare_for_run() with the BQL taken, due to the replay_mutex
uses -- here the win is cpu_handle_halt() ends restricted to system
and we can remove the odd EXCP_HLT handling in user emulation.
Makes sense, but probably it would be a series of its own. :)
Good, right.
(FYI the motivation behind these cleanups and documentation is to
get hybrid-acceleration, so a consistent vcpu_thread_routine between
accelerators:
https://lore.kernel.org/qemu-devel/[email protected]/)
