diff options
author | Dan Williams <dan.j.williams@intel.com> | 2023-04-03 14:39:16 -0700 |
---|---|---|
committer | Dan Williams <dan.j.williams@intel.com> | 2023-04-04 15:34:34 -0700 |
commit | d35b495ddf92c964eedf2ac86fdbf88dc3e5cbc9 (patch) | |
tree | dbf65694296ba30d731a8ce828199fefc64bcbce /drivers/cxl/core/region.c | |
parent | b70c2cf95ee1ca2806cb7191504920f8f5b4454e (diff) |
cxl/port: Fix find_cxl_root() for RCDs and simplify it
The find_cxl_root() helper is used to lookup root decoders and other CXL
platform topology information for a given endpoint. It turns out that
for RCDs it has never worked. The result of find_cxl_root(&cxlmd->dev)
is always NULL for the RCH topology case because it expects to find a
cxl_port at the host-bridge. RCH topologies only have the root cxl_port
object with the host-bridge as a dport. While there are no reports of
this being a problem to date, by inspection region enumeration should
crash as a result of this problem, and it does in a local unit test for
this scenario.
However, an observation that ever since:
commit f17b558d6663 ("cxl/pmem: Refactor nvdimm device registration, delete the workqueue")
...all callers of find_cxl_root() occur after the memdev connection to
the port topology has been established. That means that find_cxl_root()
can be simplified to a walk of the endpoint port topology to the root.
Switch to that arrangement which also fixes the RCD bug.
Fixes: a32320b71f08 ("cxl/region: Add region autodiscovery")
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/168002857715.50647.344876437247313909.stgit@dwillia2-xfh.jf.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Diffstat (limited to 'drivers/cxl/core/region.c')
-rw-r--r-- | drivers/cxl/core/region.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/drivers/cxl/core/region.c b/drivers/cxl/core/region.c index f29028148806..808f23ec4e2b 100644 --- a/drivers/cxl/core/region.c +++ b/drivers/cxl/core/region.c @@ -2251,7 +2251,7 @@ static struct cxl_pmem_region *cxl_pmem_region_alloc(struct cxl_region *cxlr) * bridge for one device is the same for all. */ if (i == 0) { - cxl_nvb = cxl_find_nvdimm_bridge(&cxlmd->dev); + cxl_nvb = cxl_find_nvdimm_bridge(cxlmd); if (!cxl_nvb) { cxlr_pmem = ERR_PTR(-ENODEV); goto out; |