[PATCH 0/2] delete premature free_irq

[PATCH 0/2] delete premature free_irq

[Julia Lawall]

platform_get_request, or its wrapper platform_get_irq, doesn't allocate
anything, so there is nothing to free.  Free_irq matches up with
request_irq and related functions.

The complete semantic patch used is as follows
(http://coccinelle.lip6.fr/)

// <smpl>
@@
identifier l;
statement S1;
expression e,e1;
@@

*e = platform_get_irq(...);
... when != request_irq(e,...)
    when != request_threaded_irq(e,...)
    when != request_any_context_irq(e,...)
    when != if (...) { <+... request_irq(e,...) ...+> } else S1
    when != if (...) { <+... request_threaded_irq(e,...) ...+> } else S1
    when != if (...) { <+... request_any_context_irq(e,...) ...+> } else S1
    when != e1 = e
*goto l;
...
*free_irq(e,...)

@@
identifier l;
statement S,S1;
expression e,e1;
@@

*e = platform_get_irq(...);
... when != request_irq(e,...)
    when != request_threaded_irq(e,...)
    when != request_any_context_irq(e,...)
    when != if (...) { <+... request_irq(e,...) ...+> } else S1
    when != if (...) { <+... request_threaded_irq(e,...) ...+> } else S1
    when != if (...) { <+... request_any_context_irq(e,...) ...+> } else S1
*e1 = e;
... when != request_irq(\(e\|e1\),...)
    when != request_threaded_irq(\(e\|e1\),...)
    when != request_any_context_irq(\(e\|e1\),...)
    when != if (...) { <+... request_irq(\(e\|e1\),...) ...+> } else S
    when != if (...) { <+... request_threaded_irq(\(e\|e1\),...) ...+> } else S
    when != if (...) { <+... request_any_context_irq(\(e\|e1\),...) ...+> } else S
*goto l;
...
*free_irq(\(e\|e1\),...)

@@
identifier l;
statement S;
expression e,e1;
@@

*e1 = e = platform_get_irq(...);
... when != request_irq(\(e\|e1\),...)
    when != request_threaded_irq(\(e\|e1\),...)
    when != request_any_context_irq(\(e\|e1\),...)
    when != if (...) { <+... request_irq(\(e\|e1\),...) ...+> } else S
    when != if (...) { <+... request_threaded_irq(\(e\|e1\),...) ...+> } else S
    when != if (...) { <+... request_any_context_irq(\(e\|e1\),...) ...+> } else S
*goto l;
...
*free_irq(\(e\|e1\),...)

// -------------------------------------------------------------------------

@@
identifier l;
statement S,S1;
expression e,e2,e3;
@@

*e = platform_get_resource(e2,IORESOURCE_IRQ,e3);
... when != request_irq(e->start,...)
    when != request_threaded_irq(e->start,...)
    when != request_any_context_irq(e->start,...)
    when != if (...) { <+... request_irq(e->start,...) ...+> } else S1
    when != if (...) { <+... request_threaded_irq(e->start,...) ...+> } else S1
    when != if (...) { <+... request_any_context_irq(e->start,...) ...+> } else S1
*goto l;
...
*free_irq(e->start,...)

@@
identifier l;
statement S,S1;
expression e,e1,e2,e3;
@@

*e = platform_get_resource(e2,IORESOURCE_IRQ,e3);
... when != request_irq(e->start,...)
    when != request_threaded_irq(e->start,...)
    when != request_any_context_irq(e->start,...)
    when != if (...) { <+... request_irq(e->start,...) ...+> } else S1
    when != if (...) { <+... request_threaded_irq(e->start,...) ...+> } else S1
    when != if (...) { <+... request_any_context_irq(e->start,...) ...+> } else S1
e1 = e->start;
... when != request_irq(\(e->start\|e1\),...)
    when != request_threaded_irq(\(e->start\|e1\),...)
    when != request_any_context_irq(\(e->start\|e1\),...)
    when != if (...) { <+... request_irq(\(e->start\|e1\),...) ...+> } else S
    when != if (...) { <+... request_threaded_irq(\(e->start\|e1\),...) ...+> } else S
    when != if (...) { <+... request_any_context_irq(\(e->start\|e1\),...) ...+> } else S
*goto l;
...
*free_irq(\(e->start\|e1\),...)
// </smpl>

[PATCH 2/2] drivers:net: delete premature free_irq

[Julia Lawall]

From: Julia Lawall <Julia.Lawall@lip6.fr>

Free_irq is not needed if there has been no request_irq.  Free_irq is
removed from both the probe and remove functions.  The correct request_irq
and free_irq are found in the open and close functions.

A simplified version of the semantic match that finds this problem is as
follows: (http://coccinelle.lip6.fr/)

// <smpl>
@@
expression e;
@@

*e = platform_get_irq(...);
... when != request_irq(e,...)
*free_irq(e,...)
// </smpl>

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>

---
Not tested.

 drivers/net/ethernet/nuvoton/w90p910_ether.c |   11 ++---------
 1 file changed, 2 insertions(+), 9 deletions(-)

diff --git a/drivers/net/ethernet/nuvoton/w90p910_ether.c b/drivers/net/ethernet/nuvoton/w90p910_ether.c
index dcfe58f..79645f7 100644
--- a/drivers/net/ethernet/nuvoton/w90p910_ether.c
+++ b/drivers/net/ethernet/nuvoton/w90p910_ether.c
@@ -1014,7 +1014,7 @@ static int w90p910_ether_probe(struct platform_device *pdev)
 	if (ether->rxirq < 0) {
 		dev_err(&pdev->dev, "failed to get ether rx irq\n");
 		error = -ENXIO;
-		goto failed_free_txirq;
+		goto failed_free_io;
 	}
 
 	platform_set_drvdata(pdev, dev);
@@ -1023,7 +1023,7 @@ static int w90p910_ether_probe(struct platform_device *pdev)
 	if (IS_ERR(ether->clk)) {
 		dev_err(&pdev->dev, "failed to get ether clock\n");
 		error = PTR_ERR(ether->clk);
-		goto failed_free_rxirq;
+		goto failed_free_io;
 	}
 
 	ether->rmiiclk = clk_get(&pdev->dev, "RMII");
@@ -1049,10 +1049,6 @@ failed_put_rmiiclk:
 	clk_put(ether->rmiiclk);
 failed_put_clk:
 	clk_put(ether->clk);
-failed_free_rxirq:
-	free_irq(ether->rxirq, pdev);
-failed_free_txirq:
-	free_irq(ether->txirq, pdev);
 failed_free_io:
 	iounmap(ether->reg);
 failed_free_mem:
@@ -1075,9 +1071,6 @@ static int w90p910_ether_remove(struct platform_device *pdev)
 	iounmap(ether->reg);
 	release_mem_region(ether->res->start, resource_size(ether->res));
 
-	free_irq(ether->txirq, dev);
-	free_irq(ether->rxirq, dev);
-
 	del_timer_sync(&ether->check_timer);
 
 	free_netdev(dev);

Re: [PATCH 2/2] drivers:net: delete premature free_irq

[David Miller]

From: Julia Lawall <Julia.Lawall@lip6.fr>
Date: Mon,  2 Sep 2013 11:54:21 +0200

> From: Julia Lawall <Julia.Lawall@lip6.fr>
> 
> Free_irq is not needed if there has been no request_irq.  Free_irq is
> removed from both the probe and remove functions.  The correct request_irq
> and free_irq are found in the open and close functions.
> 
> A simplified version of the semantic match that finds this problem is as
> follows: (http://coccinelle.lip6.fr/)
 ...
> Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>

Applied, thank you.