* Re: [PATCH v2] mailbox: don't free the channel if the startup callback failed
2026-04-20 11:41 [PATCH v2] mailbox: don't free the channel if the startup callback failed Wolfram Sang
@ 2026-04-21 15:07 ` kernel test robot
2026-04-22 10:43 ` kernel test robot
1 sibling, 0 replies; 3+ messages in thread
From: kernel test robot @ 2026-04-21 15:07 UTC (permalink / raw)
To: Wolfram Sang, linux-renesas-soc
Cc: oe-kbuild-all, linux-kernel, Wolfram Sang, Jassi Brar, Mark Brown
Hi Wolfram,
kernel test robot noticed the following build errors:
[auto build test ERROR on jassibrar-mailbox/for-next]
[also build test ERROR on next-20260420]
[cannot apply to linus/master v7.0]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]
url: https://github.com/intel-lab-lkp/linux/commits/Wolfram-Sang/mailbox-don-t-free-the-channel-if-the-startup-callback-failed/20260420-234226
base: https://git.kernel.org/pub/scm/linux/kernel/git/jassibrar/mailbox.git for-next
patch link: https://lore.kernel.org/r/20260420114346.10586-2-wsa%2Brenesas%40sang-engineering.com
patch subject: [PATCH v2] mailbox: don't free the channel if the startup callback failed
config: m68k-allmodconfig (https://download.01.org/0day-ci/archive/20260421/202604212338.ff2P1FQg-lkp@intel.com/config)
compiler: m68k-linux-gcc (GCC) 15.2.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20260421/202604212338.ff2P1FQg-lkp@intel.com/reproduce)
If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202604212338.ff2P1FQg-lkp@intel.com/
All error/warnings (new ones prefixed by >>):
drivers/mailbox/mailbox.c: In function '__mbox_bind_client':
>> drivers/mailbox/mailbox.c:355:25: error: implicit declaration of function 'mbox_clean_and_put_channel' [-Wimplicit-function-declaration]
355 | mbox_clean_and_put_channel(chan);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~
drivers/mailbox/mailbox.c: At top level:
>> drivers/mailbox/mailbox.c:484:6: warning: no previous prototype for 'mbox_clean_and_put_channel' [-Wmissing-prototypes]
484 | void mbox_clean_and_put_channel(struct mbox_chan *chan)
| ^~~~~~~~~~~~~~~~~~~~~~~~~~
>> drivers/mailbox/mailbox.c:484:6: warning: conflicting types for 'mbox_clean_and_put_channel'; have 'void(struct mbox_chan *)'
drivers/mailbox/mailbox.c:355:25: note: previous implicit declaration of 'mbox_clean_and_put_channel' with type 'void(struct mbox_chan *)'
355 | mbox_clean_and_put_channel(chan);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~
vim +/mbox_clean_and_put_channel +355 drivers/mailbox/mailbox.c
329
330 static int __mbox_bind_client(struct mbox_chan *chan, struct mbox_client *cl)
331 {
332 struct device *dev = cl->dev;
333 int ret;
334
335 if (chan->cl || !try_module_get(chan->mbox->dev->driver->owner)) {
336 dev_err(dev, "%s: mailbox not free\n", __func__);
337 return -EBUSY;
338 }
339
340 scoped_guard(spinlock_irqsave, &chan->lock) {
341 chan->msg_free = 0;
342 chan->msg_count = 0;
343 chan->active_req = MBOX_NO_MSG;
344 chan->cl = cl;
345 init_completion(&chan->tx_complete);
346
347 if (chan->txdone_method == MBOX_TXDONE_BY_POLL && cl->knows_txdone)
348 chan->txdone_method = MBOX_TXDONE_BY_ACK;
349 }
350
351 if (chan->mbox->ops->startup) {
352 ret = chan->mbox->ops->startup(chan);
353 if (ret) {
354 dev_err(dev, "Unable to startup the chan (%d)\n", ret);
> 355 mbox_clean_and_put_channel(chan);
356 return ret;
357 }
358 }
359
360 return 0;
361 }
362
363 /**
364 * mbox_bind_client - Bind client to a mailbox channel.
365 * @chan: The mailbox channel to bind the client to.
366 * @cl: Identity of the client requesting the channel.
367 *
368 * The Client specifies its requirements and capabilities while asking for
369 * a mailbox channel. It can't be called from atomic context.
370 * The channel is exclusively allocated and can't be used by another
371 * client before the owner calls mbox_free_channel.
372 * After assignment, any packet received on this channel will be
373 * handed over to the client via the 'rx_callback'.
374 * The framework holds reference to the client, so the mbox_client
375 * structure shouldn't be modified until the mbox_free_channel returns.
376 *
377 * Return: 0 if the channel was assigned to the client successfully.
378 * <0 for request failure.
379 */
380 int mbox_bind_client(struct mbox_chan *chan, struct mbox_client *cl)
381 {
382 guard(mutex)(&con_mutex);
383
384 return __mbox_bind_client(chan, cl);
385 }
386 EXPORT_SYMBOL_GPL(mbox_bind_client);
387
388 /**
389 * mbox_request_channel - Request a mailbox channel.
390 * @cl: Identity of the client requesting the channel.
391 * @index: Index of mailbox specifier in 'mboxes' property.
392 *
393 * The Client specifies its requirements and capabilities while asking for
394 * a mailbox channel. It can't be called from atomic context.
395 * The channel is exclusively allocated and can't be used by another
396 * client before the owner calls mbox_free_channel.
397 * After assignment, any packet received on this channel will be
398 * handed over to the client via the 'rx_callback'.
399 * The framework holds reference to the client, so the mbox_client
400 * structure shouldn't be modified until the mbox_free_channel returns.
401 *
402 * Return: Pointer to the channel assigned to the client if successful.
403 * ERR_PTR for request failure.
404 */
405 struct mbox_chan *mbox_request_channel(struct mbox_client *cl, int index)
406 {
407 struct fwnode_reference_args fwspec;
408 struct fwnode_handle *fwnode;
409 struct mbox_controller *mbox;
410 struct of_phandle_args spec;
411 struct mbox_chan *chan;
412 struct device *dev;
413 unsigned int i;
414 int ret;
415
416 dev = cl->dev;
417 if (!dev) {
418 pr_debug("No owner device\n");
419 return ERR_PTR(-ENODEV);
420 }
421
422 fwnode = dev_fwnode(dev);
423 if (!fwnode) {
424 dev_dbg(dev, "No owner fwnode\n");
425 return ERR_PTR(-ENODEV);
426 }
427
428 ret = fwnode_property_get_reference_args(fwnode, "mboxes", "#mbox-cells",
429 0, index, &fwspec);
430 if (ret) {
431 dev_err(dev, "%s: can't parse \"%s\" property\n", __func__, "mboxes");
432 return ERR_PTR(ret);
433 }
434
435 spec.np = to_of_node(fwspec.fwnode);
436 spec.args_count = fwspec.nargs;
437 for (i = 0; i < spec.args_count; i++)
438 spec.args[i] = fwspec.args[i];
439
440 scoped_guard(mutex, &con_mutex) {
441 chan = ERR_PTR(-EPROBE_DEFER);
442 list_for_each_entry(mbox, &mbox_cons, node) {
443 if (device_match_fwnode(mbox->dev, fwspec.fwnode)) {
444 if (mbox->fw_xlate) {
445 chan = mbox->fw_xlate(mbox, &fwspec);
446 if (!IS_ERR(chan))
447 break;
448 } else if (mbox->of_xlate) {
449 chan = mbox->of_xlate(mbox, &spec);
450 if (!IS_ERR(chan))
451 break;
452 }
453 }
454 }
455
456 fwnode_handle_put(fwspec.fwnode);
457
458 if (IS_ERR(chan))
459 return chan;
460
461 ret = __mbox_bind_client(chan, cl);
462 if (ret)
463 chan = ERR_PTR(ret);
464 }
465
466 return chan;
467 }
468 EXPORT_SYMBOL_GPL(mbox_request_channel);
469
470 struct mbox_chan *mbox_request_channel_byname(struct mbox_client *cl,
471 const char *name)
472 {
473 int index = device_property_match_string(cl->dev, "mbox-names", name);
474
475 if (index < 0) {
476 dev_err(cl->dev, "%s() could not locate channel named \"%s\"\n",
477 __func__, name);
478 return ERR_PTR(index);
479 }
480 return mbox_request_channel(cl, index);
481 }
482 EXPORT_SYMBOL_GPL(mbox_request_channel_byname);
483
> 484 void mbox_clean_and_put_channel(struct mbox_chan *chan)
485 {
486 /* The queued TX requests are simply aborted, no callbacks are made */
487 scoped_guard(spinlock_irqsave, &chan->lock) {
488 chan->cl = NULL;
489 chan->active_req = MBOX_NO_MSG;
490 if (chan->txdone_method == MBOX_TXDONE_BY_ACK)
491 chan->txdone_method = MBOX_TXDONE_BY_POLL;
492 }
493
494 module_put(chan->mbox->dev->driver->owner);
495 }
496
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki
^ permalink raw reply [flat|nested] 3+ messages in thread* Re: [PATCH v2] mailbox: don't free the channel if the startup callback failed
2026-04-20 11:41 [PATCH v2] mailbox: don't free the channel if the startup callback failed Wolfram Sang
2026-04-21 15:07 ` kernel test robot
@ 2026-04-22 10:43 ` kernel test robot
1 sibling, 0 replies; 3+ messages in thread
From: kernel test robot @ 2026-04-22 10:43 UTC (permalink / raw)
To: Wolfram Sang, linux-renesas-soc
Cc: llvm, oe-kbuild-all, linux-kernel, Wolfram Sang, Jassi Brar,
Mark Brown
Hi Wolfram,
kernel test robot noticed the following build errors:
[auto build test ERROR on jassibrar-mailbox/for-next]
[also build test ERROR on next-20260421]
[cannot apply to linus/master v7.0]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]
url: https://github.com/intel-lab-lkp/linux/commits/Wolfram-Sang/mailbox-don-t-free-the-channel-if-the-startup-callback-failed/20260420-234226
base: https://git.kernel.org/pub/scm/linux/kernel/git/jassibrar/mailbox.git for-next
patch link: https://lore.kernel.org/r/20260420114346.10586-2-wsa%2Brenesas%40sang-engineering.com
patch subject: [PATCH v2] mailbox: don't free the channel if the startup callback failed
config: s390-allmodconfig (https://download.01.org/0day-ci/archive/20260422/202604221846.9nkpd0oi-lkp@intel.com/config)
compiler: clang version 18.1.8 (https://github.com/llvm/llvm-project 3b5b5c1ec4a3095ab096dd780e84d7ab81f3d7ff)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20260422/202604221846.9nkpd0oi-lkp@intel.com/reproduce)
If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202604221846.9nkpd0oi-lkp@intel.com/
All errors (new ones prefixed by >>):
>> drivers/mailbox/mailbox.c:355:4: error: call to undeclared function 'mbox_clean_and_put_channel'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]
355 | mbox_clean_and_put_channel(chan);
| ^
>> drivers/mailbox/mailbox.c:484:6: error: conflicting types for 'mbox_clean_and_put_channel'
484 | void mbox_clean_and_put_channel(struct mbox_chan *chan)
| ^
drivers/mailbox/mailbox.c:355:4: note: previous implicit declaration is here
355 | mbox_clean_and_put_channel(chan);
| ^
2 errors generated.
vim +/mbox_clean_and_put_channel +355 drivers/mailbox/mailbox.c
329
330 static int __mbox_bind_client(struct mbox_chan *chan, struct mbox_client *cl)
331 {
332 struct device *dev = cl->dev;
333 int ret;
334
335 if (chan->cl || !try_module_get(chan->mbox->dev->driver->owner)) {
336 dev_err(dev, "%s: mailbox not free\n", __func__);
337 return -EBUSY;
338 }
339
340 scoped_guard(spinlock_irqsave, &chan->lock) {
341 chan->msg_free = 0;
342 chan->msg_count = 0;
343 chan->active_req = MBOX_NO_MSG;
344 chan->cl = cl;
345 init_completion(&chan->tx_complete);
346
347 if (chan->txdone_method == MBOX_TXDONE_BY_POLL && cl->knows_txdone)
348 chan->txdone_method = MBOX_TXDONE_BY_ACK;
349 }
350
351 if (chan->mbox->ops->startup) {
352 ret = chan->mbox->ops->startup(chan);
353 if (ret) {
354 dev_err(dev, "Unable to startup the chan (%d)\n", ret);
> 355 mbox_clean_and_put_channel(chan);
356 return ret;
357 }
358 }
359
360 return 0;
361 }
362
363 /**
364 * mbox_bind_client - Bind client to a mailbox channel.
365 * @chan: The mailbox channel to bind the client to.
366 * @cl: Identity of the client requesting the channel.
367 *
368 * The Client specifies its requirements and capabilities while asking for
369 * a mailbox channel. It can't be called from atomic context.
370 * The channel is exclusively allocated and can't be used by another
371 * client before the owner calls mbox_free_channel.
372 * After assignment, any packet received on this channel will be
373 * handed over to the client via the 'rx_callback'.
374 * The framework holds reference to the client, so the mbox_client
375 * structure shouldn't be modified until the mbox_free_channel returns.
376 *
377 * Return: 0 if the channel was assigned to the client successfully.
378 * <0 for request failure.
379 */
380 int mbox_bind_client(struct mbox_chan *chan, struct mbox_client *cl)
381 {
382 guard(mutex)(&con_mutex);
383
384 return __mbox_bind_client(chan, cl);
385 }
386 EXPORT_SYMBOL_GPL(mbox_bind_client);
387
388 /**
389 * mbox_request_channel - Request a mailbox channel.
390 * @cl: Identity of the client requesting the channel.
391 * @index: Index of mailbox specifier in 'mboxes' property.
392 *
393 * The Client specifies its requirements and capabilities while asking for
394 * a mailbox channel. It can't be called from atomic context.
395 * The channel is exclusively allocated and can't be used by another
396 * client before the owner calls mbox_free_channel.
397 * After assignment, any packet received on this channel will be
398 * handed over to the client via the 'rx_callback'.
399 * The framework holds reference to the client, so the mbox_client
400 * structure shouldn't be modified until the mbox_free_channel returns.
401 *
402 * Return: Pointer to the channel assigned to the client if successful.
403 * ERR_PTR for request failure.
404 */
405 struct mbox_chan *mbox_request_channel(struct mbox_client *cl, int index)
406 {
407 struct fwnode_reference_args fwspec;
408 struct fwnode_handle *fwnode;
409 struct mbox_controller *mbox;
410 struct of_phandle_args spec;
411 struct mbox_chan *chan;
412 struct device *dev;
413 unsigned int i;
414 int ret;
415
416 dev = cl->dev;
417 if (!dev) {
418 pr_debug("No owner device\n");
419 return ERR_PTR(-ENODEV);
420 }
421
422 fwnode = dev_fwnode(dev);
423 if (!fwnode) {
424 dev_dbg(dev, "No owner fwnode\n");
425 return ERR_PTR(-ENODEV);
426 }
427
428 ret = fwnode_property_get_reference_args(fwnode, "mboxes", "#mbox-cells",
429 0, index, &fwspec);
430 if (ret) {
431 dev_err(dev, "%s: can't parse \"%s\" property\n", __func__, "mboxes");
432 return ERR_PTR(ret);
433 }
434
435 spec.np = to_of_node(fwspec.fwnode);
436 spec.args_count = fwspec.nargs;
437 for (i = 0; i < spec.args_count; i++)
438 spec.args[i] = fwspec.args[i];
439
440 scoped_guard(mutex, &con_mutex) {
441 chan = ERR_PTR(-EPROBE_DEFER);
442 list_for_each_entry(mbox, &mbox_cons, node) {
443 if (device_match_fwnode(mbox->dev, fwspec.fwnode)) {
444 if (mbox->fw_xlate) {
445 chan = mbox->fw_xlate(mbox, &fwspec);
446 if (!IS_ERR(chan))
447 break;
448 } else if (mbox->of_xlate) {
449 chan = mbox->of_xlate(mbox, &spec);
450 if (!IS_ERR(chan))
451 break;
452 }
453 }
454 }
455
456 fwnode_handle_put(fwspec.fwnode);
457
458 if (IS_ERR(chan))
459 return chan;
460
461 ret = __mbox_bind_client(chan, cl);
462 if (ret)
463 chan = ERR_PTR(ret);
464 }
465
466 return chan;
467 }
468 EXPORT_SYMBOL_GPL(mbox_request_channel);
469
470 struct mbox_chan *mbox_request_channel_byname(struct mbox_client *cl,
471 const char *name)
472 {
473 int index = device_property_match_string(cl->dev, "mbox-names", name);
474
475 if (index < 0) {
476 dev_err(cl->dev, "%s() could not locate channel named \"%s\"\n",
477 __func__, name);
478 return ERR_PTR(index);
479 }
480 return mbox_request_channel(cl, index);
481 }
482 EXPORT_SYMBOL_GPL(mbox_request_channel_byname);
483
> 484 void mbox_clean_and_put_channel(struct mbox_chan *chan)
485 {
486 /* The queued TX requests are simply aborted, no callbacks are made */
487 scoped_guard(spinlock_irqsave, &chan->lock) {
488 chan->cl = NULL;
489 chan->active_req = MBOX_NO_MSG;
490 if (chan->txdone_method == MBOX_TXDONE_BY_ACK)
491 chan->txdone_method = MBOX_TXDONE_BY_POLL;
492 }
493
494 module_put(chan->mbox->dev->driver->owner);
495 }
496
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki
^ permalink raw reply [flat|nested] 3+ messages in thread