Re: [PATCH v6 13/15] net: qrtr: limit endpoint range to 16 bits on 32-bit machines

On Tue,  1 Sep 2026 16:19:32 +0300 Juha-Matti Tilli wrote:

On 64-bit machines, use the full range for endpoint ids, but on 32-bit
machines, use only 16 bits. This gives plenty of endpoints, 65534 to
be specific, apart from the invalid zero value and the local endpoint.

This should fix any issues where a long-running system with lots of
allocations might allocate an endpoint id bigger than 65535 on a 32-bit
system. The node id, the secondary part, is already combined with port
id into a value that is potentially 32 bits in existing old code.

NOTE: please don't merge yet. This commit will have to be either
squashed or removed.

Doesn't build on 32bit x86:

../net/qrtr/af_qrtr.c: In function ‘qrtr_endpoint_register’:
../net/qrtr/af_qrtr.c:28:58: error: ‘UINT16_MAX’ undeclared (first use in this function)
   28 | #define QRTR_ENDPOINT_RANGE XA_LIMIT(qrtr_local_nid + 1, UINT16_MAX)
      |                                                          ^~~~~~~~~~
../include/linux/xarray.h:248:70: note: in definition of macro ‘XA_LIMIT’
  248 | #define XA_LIMIT(_min, _max) (struct xa_limit) { .min = _min, .max = _max }
      |                                                                      ^~~~
../net/qrtr/af_qrtr.c:746:30: note: in expansion of macro ‘QRTR_ENDPOINT_RANGE’
  746 |                              QRTR_ENDPOINT_RANGE, &next_endpoint_id,
      |                              ^~~~~~~~~~~~~~~~~~~
../net/qrtr/af_qrtr.c:16:1: note: ‘UINT16_MAX’ is defined in header ‘<stdint.h>’; this is probably fixable by adding ‘#include <stdint.h>’
   15 | #include "qrtr.h"
  +++ |+#include <stdint.h>
   16 | 
../net/qrtr/af_qrtr.c:28:58: note: each undeclared identifier is reported only once for each function it appears in
   28 | #define QRTR_ENDPOINT_RANGE XA_LIMIT(qrtr_local_nid + 1, UINT16_MAX)
      |                                                          ^~~~~~~~~~
../include/linux/xarray.h:248:70: note: in definition of macro ‘XA_LIMIT’
  248 | #define XA_LIMIT(_min, _max) (struct xa_limit) { .min = _min, .max = _max }
      |                                                                      ^~~~
../net/qrtr/af_qrtr.c:746:30: note: in expansion of macro ‘QRTR_ENDPOINT_RANGE’
  746 |                              QRTR_ENDPOINT_RANGE, &next_endpoint_id,
      |                              ^~~~~~~~~~~~~~~~~~~