Re: [PATCH 4/4] hw/pci: Ensure pci_add_capability() is called before device is realized

[Philippe Mathieu-Daudé]

On 22/3/23 03:18, Michael S. Tsirkin wrote:
> On Tue, Mar 14, 2023 at 12:14:35PM +0100, Philippe Mathieu-Daudé wrote:
> > PCI capabilities can't appear magically at runtime.
> > Guests aren't expecting that. Assert all capabilities
> > are added _before_ a device instance is realized.
> >
> > Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
> > ---
> >   hw/pci/pci.c | 4 +++-
> >   1 file changed, 3 insertions(+), 1 deletion(-)
> >
> > diff --git a/hw/pci/pci.c b/hw/pci/pci.c
> > index ac41fcbf6a..ed60b352e4 100644
> > --- a/hw/pci/pci.c
> > +++ b/hw/pci/pci.c
> > @@ -2397,7 +2397,7 @@ static void pci_del_option_rom(PCIDevice *pdev)
> >    * On success, pci_add_capability() returns a positive value
> >    * that the offset of the pci capability.
> >    * On failure, it sets an error and returns a negative error
> > - * code.
> > + * code. @pdev must be unrealized.
> >    */
> >   int pci_add_capability(PCIDevice *pdev, uint8_t cap_id,
> >                          uint8_t offset, uint8_t size,
> > @@ -2406,6 +2406,8 @@ int pci_add_capability(PCIDevice *pdev, uint8_t cap_id,
> >       uint8_t *config;
> >       int i, overlapping_cap;
> >   
> > +    assert(!DEVICE(pdev)->realized);
> > +
> >       if (!offset) {
> >           offset = pci_find_space(pdev, size);
> >           /* out of PCI config space is programming error */
>
> Fails in CI:
>
> https://gitlab.com/mstredhat/qemu/-/jobs/3976974199
>
> qemu-system-i386: ../hw/pci/pci.c:2409: pci_add_capability: Assertion 
> `!DEVICE(pdev)->realized' failed.
> Broken pipe
> ../tests/qtest/libqtest.c:193: kill_qemu() detected QEMU death from signal 6 
> (Aborted) (core dumped)
> TAP parsing error: Too few tests run (expected 49, got 40)
> (test program exited with status code -6)

Thanks for testing!

Likely the AMD-Vi device, see on the cover this series is
Based-on: <20230313153031.86107-1-philmd@linaro.org>
          "hw/i386/amd_iommu: Orphanize & QDev cleanups"
20230313153031.86107-1-philmd@linaro.org/">https://lore.kernel.org/qemu-devel/20230313153031.86107-1-philmd@linaro.org/