[PATCHv2] crypto: talitos: fix probe IRQ ordering

[Rosen Penev <rosenp@gmail.com>]

The talitos interrupt handlers schedule priv->done_task[] via
tasklet_schedule().  In probe(), talitos_probe_irq() ran before
tasklet_init(), so an interrupt arriving during that window (a shared
IRQ, or a completion pending from an earlier transmission) would
schedule an uninitialized tasklet.

Resolve the IRQ numbers before the tasklet_init() calls so the
done_task[] selection can see the secondary IRQ, and only request the
IRQs after the channel fifos are allocated and the device is
initialized.  Every structure the handlers touch is then fully set up
before interrupts are enabled.  This matches remove(), which frees the
IRQs before killing the tasklets.

Assisted-by: LLM
Signed-off-by: Rosen Penev <rosenp@gmail.com>
---
 v2: reshuffle code to avoid NULL derefs
 drivers/crypto/talitos.c | 33 +++++++++++++++++++++++----------
 1 file changed, 23 insertions(+), 10 deletions(-)

diff --git a/drivers/crypto/talitos.c b/drivers/crypto/talitos.c
index 41a87d7c30a0..b9dfa2b7ccbb 100644
--- a/drivers/crypto/talitos.c
+++ b/drivers/crypto/talitos.c
@@ -3346,28 +3346,36 @@ static struct talitos_crypto_alg *talitos_alg_alloc(struct device *dev,
 	return t_alg;
 }
 
-static int talitos_probe_irq(struct platform_device *ofdev)
+static int talitos_get_irqs(struct platform_device *ofdev)
 {
 	struct device *dev = &ofdev->dev;
 	struct talitos_private *priv = dev_get_drvdata(dev);
-	int err;
-	bool is_sec1 = has_ftr_sec1(priv);
 
 	priv->irq[0] = platform_get_irq(ofdev, 0);
 	if (priv->irq[0] < 0)
 		return priv->irq[0];
 
+	priv->irq[1] = platform_get_irq_optional(ofdev, 1);
+	if (priv->irq[1] == -EPROBE_DEFER)
+		return priv->irq[1];
+
+	return 0;
+}
+
+static int talitos_probe_irq(struct platform_device *ofdev)
+{
+	struct device *dev = &ofdev->dev;
+	struct talitos_private *priv = dev_get_drvdata(dev);
+	int err;
+	bool is_sec1 = has_ftr_sec1(priv);
+
 	if (is_sec1) {
 		err = request_irq(priv->irq[0], talitos1_interrupt_4ch, 0,
 				  dev_driver_string(dev), priv);
 		goto primary_out;
 	}
 
-	priv->irq[1] = platform_get_irq_optional(ofdev, 1);
-	if (priv->irq[1] == -EPROBE_DEFER)
-		return priv->irq[1];
-
-	/* get the primary irq line */
+	/* single (or primary) irq line */
 	if (priv->irq[1] < 0) {
 		err = request_irq(priv->irq[0], talitos2_interrupt_4ch, 0,
 				  dev_driver_string(dev), priv);
@@ -3379,7 +3387,7 @@ static int talitos_probe_irq(struct platform_device *ofdev)
 	if (err)
 		goto primary_out;
 
-	/* get the secondary irq line */
+	/* secondary irq line */
 	err = request_irq(priv->irq[1], talitos2_interrupt_ch1_3, 0,
 			  dev_driver_string(dev), priv);
 	if (err) {
@@ -3481,7 +3489,7 @@ static int talitos_probe(struct platform_device *ofdev)
 		stride = TALITOS2_CH_STRIDE;
 	}
 
-	err = talitos_probe_irq(ofdev);
+	err = talitos_get_irqs(ofdev);
 	if (err)
 		goto err_out;
 
@@ -3540,6 +3548,11 @@ static int talitos_probe(struct platform_device *ofdev)
 		goto err_out;
 	}
 
+	/* enable interrupts once the channel fifos and tasklets are set up */
+	err = talitos_probe_irq(ofdev);
+	if (err)
+		goto err_out;
+
 	/* register the RNG, if available */
 	if (hw_supports(dev, DESC_HDR_SEL0_RNG)) {
 		err = talitos_register_rng(dev);
-- 
2.55.0