[PATCH] PCI: keystone: fix crash with deferred probe

Jisheng Zhang
2015-11-23T11:27:17Z

On Mon, 23 Nov 2015 19:22:09 +0800
Jisheng Zhang <jszhang@marvell.com> wrote:

> Dear Sekhar,
>
> On Fri, 20 Nov 2015 16:47:02 +0530
> Sekhar Nori wrote:
>
> > Drop __init annotations for functions called during
> > probe of keystone PCIe host.
> >
> > This fixes kernel crashes seen because of init data
> > reclamation if the driver defer probes because of
> > phy unavailability.
> >
> > While at it, drop the useless __refdata annotation
> > to driver structure. If its really needed, it should
> > be added back with a comment explaining why.
> >
> > Signed-off-by: Sekhar Nori <nsekhar@ti.com>
> > ---
> > drivers/pci/host/pci-keystone-dw.c | 2 +-
> > drivers/pci/host/pci-keystone.c | 6 +++---
> > 2 files changed, 4 insertions(+), 4 deletions(-)
> >
> > diff --git a/drivers/pci/host/pci-keystone-dw.c b/drivers/pci/host/pci-keystone-dw.c
> > index ed34c9520a02..47ddbcce53ca 100644
> > --- a/drivers/pci/host/pci-keystone-dw.c
> > +++ b/drivers/pci/host/pci-keystone-dw.c
> > @@ -469,7 +469,7 @@ void ks_dw_pcie_initiate_link_train(struct keystone_pcie *ks_pcie)
> > * and call dw_pcie_v3_65_host_init() API to initialize the Keystone
> > * PCI host controller.
> > */
> > -int __init ks_dw_pcie_host_init(struct keystone_pcie *ks_pcie,
> > +int ks_dw_pcie_host_init(struct keystone_pcie *ks_pcie,
> > struct device_node *msi_intc_np)
>
> when trying to add berlin pcie support and came up one patch
>
> http://lists.infradead.org/pipermail/linux-arm-kernel/2015-November/384575.html
>
> when build testing, I also realized this issue, but keystone relies on

I mean ks_dw_pcie_host_init() calls hook_fault_code()

> hook_fault_code() which is will be freed after boot, so your patch isn't
> completed.

And will introduce section mismatch warnings

>
> And from the keystone driver implementation, it seems assume the driver won't
> be defer probed.
>
> Thanks
>
> > {
> > struct pcie_port *pp = &ks_pcie->pp;
> > diff --git a/drivers/pci/host/pci-keystone.c b/drivers/pci/host/pci-keystone.c
> > index 0aa81bd3de12..593a58834c7d 100644
> > --- a/drivers/pci/host/pci-keystone.c
> > +++ b/drivers/pci/host/pci-keystone.c
> > @@ -291,7 +291,7 @@ static struct pcie_host_ops keystone_pcie_host_ops = {
> > .scan_bus = ks_dw_pcie_v3_65_scan_bus,
> > };
> >
> > -static int __init ks_add_pcie_port(struct keystone_pcie *ks_pcie,
> > +static int ks_add_pcie_port(struct keystone_pcie *ks_pcie,
> > struct platform_device *pdev)
> > {
> > struct pcie_port *pp = &ks_pcie->pp;
> > @@ -340,7 +340,7 @@ static int __exit ks_pcie_remove(struct platform_device *pdev)
> > return 0;
> > }
> >
> > -static int __init ks_pcie_probe(struct platform_device *pdev)
> > +static int ks_pcie_probe(struct platform_device *pdev)
> > {
> > struct device *dev = &pdev->dev;
> > struct keystone_pcie *ks_pcie;
> > @@ -396,7 +396,7 @@ fail_clk:
> > return ret;
> > }
> >
> > -static struct platform_driver ks_pcie_driver __refdata = {
> > +static struct platform_driver ks_pcie_driver = {
> > .probe = ks_pcie_probe,
> > .remove = __exit_p(ks_pcie_remove),
> > .driver = {
>