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From:   Armin Wolf <W_Armin@gmx.de>
To:     rafael@kernel.org, lenb@kernel.org
Cc:     linux-acpi@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: [PATCH v3 2/3] ACPI: EC: Fix oops when removing custom query handlers
Date:   Fri, 24 Mar 2023 21:26:27 +0100
Message-Id: <20230324202628.76966-3-W_Armin@gmx.de>
In-Reply-To: <20230324202628.76966-1-W_Armin@gmx.de>
References: <20230324202628.76966-1-W_Armin@gmx.de>
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Precedence: bulk

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>
=2D--
 drivers/acpi/ec.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/acpi/ec.c b/drivers/acpi/ec.c
index f84905dbd8ca..4ae017391533 100644
=2D-- a/drivers/acpi/ec.c
+++ b/drivers/acpi/ec.c
@@ -1132,6 +1132,7 @@ static void acpi_ec_remove_query_handlers(struct acp=
i_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);

=2D-
2.30.2