Re: [PATCH] genirq/msi: Fix unpaired calls in msi

From: Bixuan Cui
Date: Tue Jun 01 2021 - 03:53:50 EST


A gentle ping :)

Thanks
Bixuan Cui

On 2021/5/18 11:31, Bixuan Cui wrote:
> There are unpaired calls in the msi:
>
> msi_domain_alloc_irqs() {
> ...
> __irq_domain_alloc_irqs()
> ...
> irq_domain_activate_irq()
> }
>
> msi_domain_free_irqs() {
> ...
> irq_domain_free_irqs()
> }
>
> When msi_domain_alloc_irqs() and msi_domain_free_irqs() are called in
> pairs, the irq_domain_deactivate_irq() is missing calls.
>
> This problem occurs during PCI initialization.After pci_msi_setup_msi_irqs
> is executed (invoke irq_domain_activate_irq to initialize the MSI irq),
> error_cleanup_irqs() of pcie_port_device_register() is executed.
> As follows:
>
> pcie_port_device_register() {
> ...
>
> error_cleanup_irqs:
> pci_free_irq_vectors(dev);
> }
>
> Invoking Procedure:
> pcie_port_device_register
> -> goto error_cleanup_irqs
> -> pci_free_irq_vectors(dev);
> pci_disable_msi
> free_msi_irqs
> pci_msi_teardown_msi_irqs
> msi_domain_free_irqs // no deactivate before free
> irq_domain_free_irqs
>
> Signed-off-by: Bixuan Cui <cuibixuan@xxxxxxxxxx>
> ---
> kernel/irq/msi.c | 13 ++++++++-----
> 1 file changed, 8 insertions(+), 5 deletions(-)
>
> diff --git a/kernel/irq/msi.c b/kernel/irq/msi.c
> index c41965e348b5..8828d4863c5d 100644
> --- a/kernel/irq/msi.c
> +++ b/kernel/irq/msi.c
> @@ -476,11 +476,6 @@ int __msi_domain_alloc_irqs(struct irq_domain *domain, struct device *dev,
> return 0;
>
> cleanup:
> - for_each_msi_vector(desc, i, dev) {
> - irq_data = irq_domain_get_irq_data(domain, i);
> - if (irqd_is_activated(irq_data))
> - irq_domain_deactivate_irq(irq_data);
> - }
> msi_domain_free_irqs(domain, dev);
> return ret;
> }
> @@ -506,6 +501,14 @@ int msi_domain_alloc_irqs(struct irq_domain *domain, struct device *dev,
> void __msi_domain_free_irqs(struct irq_domain *domain, struct device *dev)
> {
> struct msi_desc *desc;
> + struct irq_data *irq_data;
> + int i;
> +
> + for_each_msi_vector(desc, i, dev) {
> + irq_data = irq_domain_get_irq_data(domain, i);
> + if (irqd_is_activated(irq_data))
> + irq_domain_deactivate_irq(irq_data);
> + }
>
> for_each_msi_entry(desc, dev) {
> /*
>