Adam Manzanares wrote:
> On Thu, Jun 23, 2022 at 07:45:07PM -0700, Dan Williams wrote:
> > This failing signature:
> >
> > [ 8.392669] cxl_bus_probe: cxl_port endpoint2: probe: 970997760
> > [ 8.392670] cxl_port: probe of endpoint2 failed with error 970997760
> > [ 8.392719] create_endpoint: cxl_mem mem0: add: endpoint2
> > [ 8.392721] cxl_mem mem0: endpoint2 failed probe
> > [ 8.392725] cxl_bus_probe: cxl_mem mem0: probe: -6
> >
> > ...shows cxl_hdm_decode_init() resulting in a return code ("970997760")
> > that looks like stack corruption. The problem goes away if
> > cxl_hdm_decode_init() is not mocked via __wrap_cxl_hdm_decode_init().
> >
> > The corruption results from the mismatch that the calling convention for
> > cxl_hdm_decode_init() is:
> >
> > int cxl_hdm_decode_init(struct cxl_dev_state *cxlds, struct cxl_hdm *cxlhdm)
> >
> > ...and __wrap_cxl_hdm_decode_init() is:
> >
> > bool __wrap_cxl_hdm_decode_init(struct cxl_dev_state *cxlds, struct cxl_hdm
> > *cxlhdm)
> >
> > ...i.e. an int is expected but __wrap_hdm_decode_init() returns bool.
> >
> > Fix the convention and cleanup the organization to match
> > __wrap_cxl_await_media_ready() as the difference was a red herring that
> > distracted from finding the bug.
> >
> > Fixes: 92804edb11f0 ("cxl/pci: Drop @info argument to
> > cxl_hdm_decode_init()")
> > Signed-off-by: Dan Williams <[email protected]>
> > ---
> > tools/testing/cxl/test/mock.c | 8 +++++---
> > 1 file changed, 5 insertions(+), 3 deletions(-)
> >
> > diff --git a/tools/testing/cxl/test/mock.c b/tools/testing/cxl/test/mock.c
> > index f1f8c40948c5..bce6a21df0d5 100644
> > --- a/tools/testing/cxl/test/mock.c
> > +++ b/tools/testing/cxl/test/mock.c
> > @@ -208,13 +208,15 @@ int __wrap_cxl_await_media_ready(struct cxl_dev_state
> > *cxlds)
> > }
> > EXPORT_SYMBOL_NS_GPL(__wrap_cxl_await_media_ready, CXL);
> >
> > -bool __wrap_cxl_hdm_decode_init(struct cxl_dev_state *cxlds,
> > - struct cxl_hdm *cxlhdm)
> > +int __wrap_cxl_hdm_decode_init(struct cxl_dev_state *cxlds,
> > + struct cxl_hdm *cxlhdm)
> > {
> > int rc = 0, index;
> > struct cxl_mock_ops *ops = get_cxl_mock_ops(&index);
> >
> > - if (!ops || !ops->is_mock_dev(cxlds->dev))
> > + if (ops && ops->is_mock_dev(cxlds->dev))
> > + rc = 0;
> > + else
> > rc = cxl_hdm_decode_init(cxlds, cxlhdm);
> > put_cxl_mock_ops(index);
> >
> >
>
>
> Looks good.
>
> Reviewed by: Adam Manzanares <[email protected]>
Just fyi, b4 did not auto-apply this tag due to the missing "-", caught
it manually.