Patch "dpll: fix dpll_xa_ref_*_del() for multiple registrations" has been added to the 6.7-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

This is a note to let you know that I've just added the patch titled

    dpll: fix dpll_xa_ref_*_del() for multiple registrations

to the 6.7-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     dpll-fix-dpll_xa_ref_-_del-for-multiple-registration.patch
and it can be found in the queue-6.7 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.



commit f77f60737da8c4dcb73a8484615b19b8368ebd10
Author: Jiri Pirko <jiri@xxxxxxxxxxx>
Date:   Wed Mar 6 16:12:40 2024 +0100

    dpll: fix dpll_xa_ref_*_del() for multiple registrations
    
    [ Upstream commit b446631f355ece73b13c311dd712c47381a23172 ]
    
    Currently, if there are multiple registrations of the same pin on the
    same dpll device, following warnings are observed:
    WARNING: CPU: 5 PID: 2212 at drivers/dpll/dpll_core.c:143 dpll_xa_ref_pin_del.isra.0+0x21e/0x230
    WARNING: CPU: 5 PID: 2212 at drivers/dpll/dpll_core.c:223 __dpll_pin_unregister+0x2b3/0x2c0
    
    The problem is, that in both dpll_xa_ref_dpll_del() and
    dpll_xa_ref_pin_del() registration is only removed from list in case the
    reference count drops to zero. That is wrong, the registration has to
    be removed always.
    
    To fix this, remove the registration from the list and free
    it unconditionally, instead of doing it only when the ref reference
    counter reaches zero.
    
    Fixes: 9431063ad323 ("dpll: core: Add DPLL framework base functions")
    Signed-off-by: Jiri Pirko <jiri@xxxxxxxxxx>
    Reviewed-by: Rahul Rameshbabu <rrameshbabu@xxxxxxxxxx>
    Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

diff --git a/drivers/dpll/dpll_core.c b/drivers/dpll/dpll_core.c
index f8fbf03942888..e72ebdf621509 100644
--- a/drivers/dpll/dpll_core.c
+++ b/drivers/dpll/dpll_core.c
@@ -128,9 +128,9 @@ static int dpll_xa_ref_pin_del(struct xarray *xa_pins, struct dpll_pin *pin,
 		reg = dpll_pin_registration_find(ref, ops, priv);
 		if (WARN_ON(!reg))
 			return -EINVAL;
+		list_del(&reg->list);
+		kfree(reg);
 		if (refcount_dec_and_test(&ref->refcount)) {
-			list_del(&reg->list);
-			kfree(reg);
 			xa_erase(xa_pins, i);
 			WARN_ON(!list_empty(&ref->registration_list));
 			kfree(ref);
@@ -208,9 +208,9 @@ dpll_xa_ref_dpll_del(struct xarray *xa_dplls, struct dpll_device *dpll,
 		reg = dpll_pin_registration_find(ref, ops, priv);
 		if (WARN_ON(!reg))
 			return;
+		list_del(&reg->list);
+		kfree(reg);
 		if (refcount_dec_and_test(&ref->refcount)) {
-			list_del(&reg->list);
-			kfree(reg);
 			xa_erase(xa_dplls, i);
 			WARN_ON(!list_empty(&ref->registration_list));
 			kfree(ref);