Re: [tip:irq/urgent] PCI/keystone: Fix race in installing chained IRQ handler

Re: [tip:irq/urgent] PCI/keystone: Fix race in installing chained IRQ handler

[Murali Karicheri]

On 06/26/2015 03:44 PM, tip-bot for Thomas Gleixner wrote:
> Commit-ID:  2cf5a03cb29debb00681a8af1dfa9179b43404d1
> Gitweb:     http://git.kernel.org/tip/2cf5a03cb29debb00681a8af1dfa9179b43404d1
> Author:     Thomas Gleixner <tglx@linutronix.de>
> AuthorDate: Sun, 21 Jun 2015 20:16:09 +0200
> Committer:  Thomas Gleixner <tglx@linutronix.de>
> CommitDate: Thu, 25 Jun 2015 11:57:01 +0200
>
> PCI/keystone: Fix race in installing chained IRQ handler
>
> Fix a race where a pending interrupt could be received and the handler
> called before the handler's data has been setup, by converting to
> irq_set_chained_handler_and_data().
>
> Search and conversion was done with coccinelle:
>
> @@
> expression E1, E2, E3;
> @@
> (
> -if (irq_set_chained_handler(E1, E3) != 0)
> -   BUG();
> |
> -irq_set_chained_handler(E1, E3);
> )
> -irq_set_handler_data(E1, E2);
> +irq_set_chained_handler_and_data(E1, E3, E2);
>
> @@
> expression E1, E2, E3;
> @@
> (
> -if (irq_set_chained_handler(E1, E3) != 0)
> -   BUG();
> ...
> |
> -irq_set_chained_handler(E1, E3);
> ...
> )
> -irq_set_handler_data(E1, E2);
> +irq_set_chained_handler_and_data(E1, E3, E2);
>
> Reported-by: Russell King <rmk+kernel@arm.linux.org.uk>
> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
> Cc: Julia Lawall <Julia.Lawall@lip6.fr>
> Cc: Murali Karicheri <m-karicheri2@ti.com>
> Cc: Bjorn Helgaas <bhelgaas@google.com>
> Cc: linux-pci@vger.kernel.org
> Cc: linux-arm-kernel@lists.infradead.org
> ---
>   drivers/pci/host/pci-keystone.c | 7 +++----
>   1 file changed, 3 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/pci/host/pci-keystone.c b/drivers/pci/host/pci-keystone.c
> index 75333b0..47cf0c1 100644
> --- a/drivers/pci/host/pci-keystone.c
> +++ b/drivers/pci/host/pci-keystone.c
> @@ -223,10 +223,9 @@ static void ks_pcie_setup_interrupts(struct keystone_pcie *ks_pcie)
>   	/* MSI IRQ */
>   	if (IS_ENABLED(CONFIG_PCI_MSI)) {
>   		for (i = 0; i < ks_pcie->num_msi_host_irqs; i++) {
> -			irq_set_chained_handler(ks_pcie->msi_host_irqs[i],
> -						ks_pcie_msi_irq_handler);
> -			irq_set_handler_data(ks_pcie->msi_host_irqs[i],
> -					     ks_pcie);
> +			irq_set_chained_handler_and_data(ks_pcie->msi_host_irqs[i],
> +							 ks_pcie_msi_irq_handler,
> +							 ks_pcie);
>   		}
>   	}
>   }
>
Thomas,

Thanks for the patch.

Tested-By: Murali Karicheri <m-karicheri2@ti.com>

-- 
Murali Karicheri
Linux Kernel, Keystone