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From:   Wedson Almeida Filho <wedsonaf@gmail.com>
To:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc:     "Rafael J . Wysocki" <rafael@kernel.org>,
        linux-kernel@vger.kernel.org,
        Wedson Almeida Filho <walmeida@microsoft.com>
Subject: [PATCH] driver core: update comments in device_rename()
Date:   Thu,  6 Apr 2023 01:54:35 -0300
Message-Id: <20230406045435.19452-1-wedsonaf@gmail.com>
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From: Wedson Almeida Filho <walmeida@microsoft.com>

Document that some subsystems are still going to use device_rename for
the time being, so it is not a good idea to assume it's not used. Also
remove mentions of a plan to stop renaming net devices.

Signed-off-by: Wedson Almeida Filho <walmeida@microsoft.com>
---
 drivers/base/core.c | 16 ++++++----------
 1 file changed, 6 insertions(+), 10 deletions(-)

diff --git a/drivers/base/core.c b/drivers/base/core.c
index 6878dfcbf0d6..95d414074f92 100644
--- a/drivers/base/core.c
+++ b/drivers/base/core.c
@@ -4383,9 +4383,12 @@ EXPORT_SYMBOL_GPL(device_destroy);
  * on the same device to ensure that new_name is valid and
  * won't conflict with other devices.
  *
- * Note: Don't call this function.  Currently, the networking layer calls this
- * function, but that will change.  The following text from Kay Sievers offers
- * some insight:
+ * Note: given that some subsystems (networking and infiniband) use this
+ * function, with no immediate plans for this to change, we cannot assume or
+ * require that this function not be called at all.
+ *
+ * However, if you're writing new code, do not call this function. The following
+ * text from Kay Sievers offers some insight:
  *
  * Renaming devices is racy at many levels, symlinks and other stuff are not
  * replaced atomically, and you get a "move" uevent, but it's not easy to
@@ -4399,13 +4402,6 @@ EXPORT_SYMBOL_GPL(device_destroy);
  * kernel device renaming. Besides that, it's not even implemented now for
  * other things than (driver-core wise very simple) network devices.
  *
- * We are currently about to change network renaming in udev to completely
- * disallow renaming of devices in the same namespace as the kernel uses,
- * because we can't solve the problems properly, that arise with swapping names
- * of multiple interfaces without races. Means, renaming of eth[0-9]* will only
- * be allowed to some other name than eth[0-9]*, for the aforementioned
- * reasons.
- *
  * Make up a "real" name in the driver before you register anything, or add
  * some other attributes for userspace to find the device, or use udev to add
  * symlinks -- but never rename kernel devices later, it's a complete mess. We
-- 
2.34.1