On Tue, 19 May 2026 12:18:32 +0200 Tomasz Wolski <[email protected]> wrote:
> The dax_region resource conflict in alloc_dax_region() indicates a > serious configuration problem — two subsystems (e.g. dax_hmem and > dax_cxl) are attempting to register overlapping address ranges. This is > not a transient or debug-level condition; it represents a genuine > resource conflict that an administrator needs to be aware of. > > Switch from request_resource() + dev_dbg() to > request_resource_conflict() + dev_err() so that the conflict is visible > by default and the colliding resource is identified in the message. > > Suggested-by: Dan Williams <[email protected]> > Link: > https://lore.kernel.org/linux-cxl/[email protected]/ > Signed-off-by: Tomasz Wolski <[email protected]> Seems reasonable to me Reviewed-by: Jonathan Cameron <[email protected]> > --- > drivers/dax/bus.c | 11 ++++++----- > 1 file changed, 6 insertions(+), 5 deletions(-) > > diff --git a/drivers/dax/bus.c b/drivers/dax/bus.c > index 68437c05e21d..66413c6c2ba0 100644 > --- a/drivers/dax/bus.c > +++ b/drivers/dax/bus.c > @@ -637,7 +637,7 @@ struct dax_region *alloc_dax_region(struct device > *parent, int region_id, > unsigned long flags) > { > struct dax_region *dax_region; > - int rc; > + struct resource *conflict; > > /* > * The DAX core assumes that it can store its private data in > @@ -670,10 +670,11 @@ struct dax_region *alloc_dax_region(struct device > *parent, int region_id, > .flags = IORESOURCE_MEM | flags, > }; > > - rc = request_resource(&dax_regions, &dax_region->res); > - if (rc) { > - dev_dbg(parent, "dax_region resource conflict for %pR\n", > - &dax_region->res); > + conflict = request_resource_conflict(&dax_regions, &dax_region->res); > + if (conflict) { > + dev_err(parent, > + "dax_region: can't claim %pR: address conflict with %s > %pR\n", > + &dax_region->res, conflict->name, conflict); > goto err_res; > } >
