Re: [Qemu-devel] [PATCH 1/2] win32: do not set CPU affinity

[Andreas Färber]

Am 20.02.2013 15:49, schrieb Peter Maydell:
> On 20 February 2013 14:43, Laszlo Ersek <address@hidden> wrote:
>> On 02/20/13 14:43, Paolo Bonzini wrote:
>>> QEMU system emulation has been thread-safe for a long time
> 
> Says who? cpu_interrupt() calls tcg_handle_interrupt()
> which calls cpu_unlink_tb() which makes changes to the
> TB datastructure with no kind of locking at all.
> 
> I'm actually working on a patchset which fixes this

A word of warning: My QOM CPUState part 9 series (v1 on the list with an
arm patch waiting for an ack, v2 upcoming) refactors and partially moves
the interrupt code, including cpu_interrupt() and
tcg_handle_interrupt(). The cpu_unlink_tb() line itself seems unaffected
though.

https://github.com/afaerber/qemu-cpu/commits/qom-cpu-9

Andreas

> (by having every TCG TB check the exit_request flag at
> the start and exit if set, so we can throw out cpu_unlink_tb()
> entirely), but as of right now the codebase is definitely
> not threadsafe.
> 
> -- PMM

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