[PATCH net] net: emac: guard PHY bitmap teardown

[PATCH net] net: emac: guard PHY bitmap teardown

[Rosen Penev]

PHY-less and fixed-link configurations retain a negative PHY address.
Avoid shifting by that value while removing the device, and serialize the
bitmap update with PHY discovery.

Fixes: d6f144830bdf ("ibm/emac: fix improper cleanup when device is removed to allow re-bind")
Signed-off-by: Rosen Penev <rosenp@gmail.com>
---
 drivers/net/ethernet/ibm/emac/core.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/ibm/emac/core.c b/drivers/net/ethernet/ibm/emac/core.c
index 4124a90b18c4..0f534af2f3de 100644
--- a/drivers/net/ethernet/ibm/emac/core.c
+++ b/drivers/net/ethernet/ibm/emac/core.c
@@ -3240,8 +3240,11 @@ static void emac_remove(struct platform_device *ofdev)
 	if (emac_has_feature(dev, EMAC_FTR_HAS_ZMII))
 		zmii_detach(dev->zmii_dev, dev->zmii_port);
 
-	busy_phy_map &= ~(1 << dev->phy.address);
+	mutex_lock(&emac_phy_map_lock);
+	if (dev->phy.address >= 0 && dev->phy.address < 32)
+		busy_phy_map &= ~BIT(dev->phy.address);
 	DBG(dev, "busy_phy_map now %#x" NL, busy_phy_map);
+	mutex_unlock(&emac_phy_map_lock);
 
 	mal_unregister_commac(dev->mal, &dev->commac);
 	emac_put_deps(dev);
-- 
2.56.0

Re: [PATCH net] net: emac: guard PHY bitmap teardown

[netdev-bot+sinfo]

Hi!

This is an automated message. This series looks like a fix, but its
commit messages seem to be missing some information:

 - How the issue was discovered, e.g. hit in production, hit during
   development, syzbot report, manual code inspection, LLM or static
   analysis tool scan.

 - Whether the issue was actually triggered, or is only theoretical
   (e.g. found by code inspection). If it was triggered please include
   the symptoms, like the stack trace or error messages.

 - What hardware the change was tested on. For driver fixes please
   mention the device (and if relevant firmware version) used for
   testing, or say that the change was not tested on real hardware.

Please do not repost the series just to address the above. Instead,
reply to this email with the missing information, so that reviewers
can take it into account. If the series needs another revision for
other reasons, please include the information in the commit messages
then.

The evaluation is done by an LLM so it may be wrong, if you think
that is the case please reply and explain.

Re: [PATCH net] net: emac: guard PHY bitmap teardown

[Rosen Penev]

On Tue, Oct 20, 2026 at 3:33 PM <netdev-bot+sinfo@kernel.org> wrote:
>
> Hi!
>
> This is an automated message. This series looks like a fix, but its
> commit messages seem to be missing some information:
>
>  - How the issue was discovered, e.g. hit in production, hit during
>    development, syzbot report, manual code inspection, LLM or static
>    analysis tool scan.
LLM
>
>  - Whether the issue was actually triggered, or is only theoretical
>    (e.g. found by code inspection). If it was triggered please include
>    the symptoms, like the stack trace or error messages.
>
>  - What hardware the change was tested on. For driver fixes please
>    mention the device (and if relevant firmware version) used for
>    testing, or say that the change was not tested on real hardware.
>
> Please do not repost the series just to address the above. Instead,
> reply to this email with the missing information, so that reviewers
> can take it into account. If the series needs another revision for
> other reasons, please include the information in the commit messages
> then.
>
> The evaluation is done by an LLM so it may be wrong, if you think
> that is the case please reply and explain.