On Fri, Jun 19, 2015 at 6:20 PM, Rafael J. Wysocki [off-list ref] wrote:

On Friday, June 19, 2015 03:36:46 PM Tomeu Vizoso wrote:

quoted

On 18 June 2015 at 23:50, Rafael J. Wysocki [off-list ref] wrote:

quoted

On Wednesday, June 17, 2015 03:42:12 PM Tomeu Vizoso wrote:

quoted

To decrease the chances of devices deferring their probes because of
dependencies not having probed yet because of their drivers not having
registered yet, delay all probing until the late initcall level.

This will allow us to avoid deferred probes completely later by probing
dependencies on demand, or by probing them in dependency order.

Signed-off-by: Tomeu Vizoso <redacted>
---
 drivers/base/dd.c | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/drivers/base/dd.c b/drivers/base/dd.c
index a638bbb..18438aa 100644
--- a/drivers/base/dd.c
+++ b/drivers/base/dd.c

@@ -407,6 +407,12 @@ int driver_probe_device(struct device_driver *drv, struct device *dev)
      if (!device_is_registered(dev))
              return -ENODEV;

+     /* Defer all probes until we start processing the queue */
+     if (!driver_deferred_probe_enable) {
+             driver_deferred_probe_add(dev);

Do I think correctly that this will effectively force everybody to use deferred
probing?

Guess it depends on the meaning of "using deferred probing". It will
defer the probe of the first device to late_initcall (which will
happen much earlier in time than before), but afterwards all built-in
drivers will be available and depending on the order in which we try
to probe devices, none may actually ask to defer its probe.

So this will break things like the PNP system driver which relies on probing
stuff at the fs_initcall stage for correctness.  It may also break other
things with similar assumptions.

Yes, but I think that this can be done for only OF based devices
rather than globally for all platform devices and solve that problem.
Matching is already dependent of the type of device.

Rob