From: Armin Wolf <W_Armin@gmx.de>
Date: Fri, 24 Mar 2023 21:26:27 +0100
Subject: [PATCH] ACPI: EC: Fix oops when removing custom query handlers
References: bsc#1012628
Patch-mainline: 6.3.4
Git-commit: e5b492c6bb900fcf9722e05f4a10924410e170c1

[ Upstream commit e5b492c6bb900fcf9722e05f4a10924410e170c1 ]

When removing custom query handlers, the handler might still
be used inside the EC query workqueue, causing a kernel oops
if the module holding the callback function was already unloaded.

Fix this by flushing the EC query workqueue when removing
custom query handlers.

Tested on a Acer Travelmate 4002WLMi

Signed-off-by: Armin Wolf <W_Armin@gmx.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
---
 drivers/acpi/ec.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/acpi/ec.c b/drivers/acpi/ec.c
index 105d2e79..9658e348 100644
--- a/drivers/acpi/ec.c
+++ b/drivers/acpi/ec.c
@@ -1122,6 +1122,7 @@ static void acpi_ec_remove_query_handlers(struct acpi_ec *ec,
 void acpi_ec_remove_query_handler(struct acpi_ec *ec, u8 query_bit)
 {
 	acpi_ec_remove_query_handlers(ec, false, query_bit);
+	flush_workqueue(ec_query_wq);
 }
 EXPORT_SYMBOL_GPL(acpi_ec_remove_query_handler);
 
-- 
2.35.3