resource: Increase MAX_IORES_LEVEL to 8

While debugging a PCI resource allocation issue, the resources for many
nested bridges and endpoints got flattened in /proc/iomem by
MAX_IORES_LEVEL that is set to 5. This made the iomem output hard to
read as the visual hierarchy cues were lost.

Increase MAX_IORES_LEVEL to 8 to avoid flattening PCI topologies with
nested bridges so aggressively (the case in the Link has the deepest
resource at level 7 so 8 looks a reasonable limit).

Link: https://bugzilla.kernel.org/show_bug.cgi?id=220775
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Link: https://patch.msgid.link/20251219174036.16738-5-ilpo.jarvinen@linux.intel.com

diff --git a/kernel/resource.c b/kernel/resource.c
index e4e9bac12e6e176d098592353a00a155ab84582a..c5f03ac78e446fd25de70059ae865686d5df129b 100644 (file)
--- a/kernel/resource.c
+++ b/kernel/resource.c
@@ -82,7 +82,7 @@ static struct resource *next_resource(struct resource *p, bool skip_children,
 
 #ifdef CONFIG_PROC_FS
 
-enum { MAX_IORES_LEVEL = 5 };
+enum { MAX_IORES_LEVEL = 8 };
 
 static void *r_start(struct seq_file *m, loff_t *pos)
        __acquires(resource_lock)