On Sat, Feb 18, 2017 at 02:26:18AM +0300, Dan Carpenter wrote:
> The bug is that "val" is unsigned long but we only initialize 32 bits
> of it. Then we test "if (val)" and that might be true not because we
> set the bits but because some were never initialized.
>
> Fixes: f342d940ee0e ("PCI: exynos: Add support for MSI")
> Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
I applied this to pci/host-designware for v4.12.
I also applied the patch below based on walter's suggestion:
commit b67d3c69df8d6721f87bbc22a587914e0d4944a7
Author: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
Date: Thu Mar 16 14:34:59 2017 -0500
PCI: dwc: Unindent dw_handle_msi_irq() loop
Use "continue" to skip rest of the loop when possible to save an indent
level. No functional change intended.
Suggested-by: walter harms <wharms@xxxxxx>
Signed-off-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
diff --git a/drivers/pci/dwc/pcie-designware-host.c b/drivers/pci/dwc/pcie-designware-host.c
index 5ba334938b52..6cdd41f06dea 100644
--- a/drivers/pci/dwc/pcie-designware-host.c
+++ b/drivers/pci/dwc/pcie-designware-host.c
@@ -63,17 +63,17 @@ irqreturn_t dw_handle_msi_irq(struct pcie_port *pp)
for (i = 0; i < MAX_MSI_CTRLS; i++) {
dw_pcie_rd_own_conf(pp, PCIE_MSI_INTR0_STATUS + i * 12, 4,
(u32 *)&val);
- if (val) {
- ret = IRQ_HANDLED;
- pos = 0;
- while ((pos = find_next_bit(&val, 32, pos)) != 32) {
- irq = irq_find_mapping(pp->irq_domain,
- i * 32 + pos);
- dw_pcie_wr_own_conf(pp, PCIE_MSI_INTR0_STATUS +
- i * 12, 4, 1 << pos);
- generic_handle_irq(irq);
- pos++;
- }
+ if (!val)
+ continue;
+
+ ret = IRQ_HANDLED;
+ pos = 0;
+ while ((pos = find_next_bit(&val, 32, pos)) != 32) {
+ irq = irq_find_mapping(pp->irq_domain, i * 32 + pos);
+ dw_pcie_wr_own_conf(pp, PCIE_MSI_INTR0_STATUS + i * 12,
+ 4, 1 << pos);
+ generic_handle_irq(irq);
+ pos++;
}
}
> ---
> Static analysis. Not tested.
>
> diff --git a/drivers/pci/dwc/pcie-designware.c b/drivers/pci/dwc/pcie-designware.c
> index af8f6e92e885..5bfc377b83e4 100644
> --- a/drivers/pci/dwc/pcie-designware.c
> +++ b/drivers/pci/dwc/pcie-designware.c
> @@ -257,17 +257,18 @@ static struct irq_chip dw_msi_irq_chip = {
> /* MSI int handler */
> irqreturn_t dw_handle_msi_irq(struct pcie_port *pp)
> {
> - unsigned long val;
> + u32 val;
> int i, pos, irq;
> irqreturn_t ret = IRQ_NONE;
>
> for (i = 0; i < MAX_MSI_CTRLS; i++) {
> dw_pcie_rd_own_conf(pp, PCIE_MSI_INTR0_STATUS + i * 12, 4,
> - (u32 *)&val);
> + &val);
> if (val) {
> ret = IRQ_HANDLED;
> pos = 0;
> - while ((pos = find_next_bit(&val, 32, pos)) != 32) {
> + while ((pos = find_next_bit((unsigned long *)&val, 32,
> + pos)) != 32) {
> irq = irq_find_mapping(pp->irq_domain,
> i * 32 + pos);
> dw_pcie_wr_own_conf(pp,
