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Guard it anyway so a future violation > of the mapping requirement fails region creation rather than causing > an oops. > > Reported-by: sashiko-bot@kernel.org > Link: https://sashiko.dev/#/patchset/cover.1787255388.git.alison.schofield%40intel.com?part=3 > Assisted-by: Claude:claude-opus-5 > Signed-off-by: Alison Schofield > --- > drivers/cxl/core/region.c | 5 +++-- > 1 file changed, 3 insertions(+), 2 deletions(-) > > diff --git a/drivers/cxl/core/region.c b/drivers/cxl/core/region.c > index 27e63e6dab7c..75b8092e6dc2 100644 > --- a/drivers/cxl/core/region.c > +++ b/drivers/cxl/core/region.c > @@ -1367,7 +1367,8 @@ static int check_last_peer(struct cxl_endpoint_decoder *cxled, > /* > * If this position wants to share a dport with the last endpoint mapped > * then that endpoint, at index 'position - distance', must also be > - * mapped by this dport. > + * mapped by this dport. An endpoint that this port does not map at all > + * fails that requirement. > */ > if (pos < distance) { > dev_dbg(&cxlr->dev, "%s:%s: cannot host %s:%s at %d\n", > @@ -1378,7 +1379,7 @@ static int check_last_peer(struct cxl_endpoint_decoder *cxled, > cxled_peer = p->targets[pos - distance]; > cxlmd_peer = cxled_to_memdev(cxled_peer); > ep_peer = cxl_ep_load(port, cxlmd_peer); > - if (ep->dport != ep_peer->dport) { > + if (!ep_peer || ep->dport != ep_peer->dport) { > dev_dbg(&cxlr->dev, > "%s:%s: %s:%s pos %d mismatched peer %s:%s\n", > dev_name(port->uport_dev), dev_name(&port->dev), > > base-commit: 7098e9cd98a05c0c5de2fae0c2465f9d966fdd07 > -- > 2.37.3 > > LGTM. Reviewed-by: Richard Cheng Best regards, Richard Cheng.