From 07eb6fdf4933336098c3e955961071e85d3dff9f Mon Sep 17 00:00:00 2001 From: Joerg Roedel Date: Wed, 9 Aug 2017 16:15:43 +0200 Subject: [PATCH] iommu/pamu: WARN when fsl_pamu_probe() is called more than once The function probes the PAMU hardware from device-tree specifications. It initializes global variables and can thus be only safely called once. Add a check that that prints a warning when its called more than once. Signed-off-by: Joerg Roedel --- drivers/iommu/fsl_pamu.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/drivers/iommu/fsl_pamu.c b/drivers/iommu/fsl_pamu.c index a34355f..9ee8e9e 100644 --- a/drivers/iommu/fsl_pamu.c +++ b/drivers/iommu/fsl_pamu.c @@ -42,6 +42,8 @@ struct pamu_isr_data { static struct paace *ppaact; static struct paace *spaact; +static bool probed; /* Has PAMU been probed? */ + /* * Table for matching compatible strings, for device tree * guts node, for QorIQ SOCs. @@ -1033,6 +1035,9 @@ static int fsl_pamu_probe(struct platform_device *pdev) * NOTE : All PAMUs share the same LIODN tables. */ + if (WARN_ON(probed)) + return -EBUSY; + pamu_regs = of_iomap(dev->of_node, 0); if (!pamu_regs) { dev_err(dev, "ioremap of PAMU node failed\n"); @@ -1172,6 +1177,8 @@ static int fsl_pamu_probe(struct platform_device *pdev) setup_liodns(); + probed = true; + return 0; error_genpool: -- 2.7.4