| Message ID | 1439569159-10051-2-git-send-email-marc.zyngier@arm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Delegated to: | Bjorn Helgaas |
| Headers | show |
On Fri, Aug 14, 2015 at 11:19 AM, Marc Zyngier <marc.zyngier@arm.com> wrote: > Both pci-host-generic and Pseries parse the "linux,pci-probe-only" > to engage the PCI_PROBE_ONLY mode, and both have a subtle bug that > can be triggered if the property has no parameter. Humm, I bet we could break a lot of machines if we fixed the core code to properly make pp->value NULL when there is no value. > Provide a generic implementation that can be used by both. > > Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> > --- > drivers/of/of_pci.c | 30 ++++++++++++++++++++++++++++++ > include/linux/of_pci.h | 3 +++ > 2 files changed, 33 insertions(+) > > diff --git a/drivers/of/of_pci.c b/drivers/of/of_pci.c > index 5751dc5..a4e29ff 100644 > --- a/drivers/of/of_pci.c > +++ b/drivers/of/of_pci.c > @@ -118,6 +118,36 @@ int of_get_pci_domain_nr(struct device_node *node) > EXPORT_SYMBOL_GPL(of_get_pci_domain_nr); > > /** > + * of_pci_check_probe_only - Setup probe only mode if linux,pci-probe-only > + * is present and valid > + * > + * @node: device tree node that may contain the property (usually "chosen") > + * > + */ > +void of_pci_check_probe_only(struct device_node *node) > +{ > + const int *prop; > + int len; > + > + if (!node) > + return; > + > + prop = of_get_property(node, "linux,pci-probe-only", &len); It is preferred to use of_property_read_u32 to avoid just these types of problems. Rob -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Fri, Aug 14, 2015 at 04:08:10PM -0500, Rob Herring wrote: > On Fri, Aug 14, 2015 at 11:19 AM, Marc Zyngier <marc.zyngier@arm.com> wrote: > > Both pci-host-generic and Pseries parse the "linux,pci-probe-only" > > to engage the PCI_PROBE_ONLY mode, and both have a subtle bug that > > can be triggered if the property has no parameter. > > Humm, I bet we could break a lot of machines if we fixed the core code > to properly make pp->value NULL when there is no value. > > > Provide a generic implementation that can be used by both. > > > > Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> > > --- > > drivers/of/of_pci.c | 30 ++++++++++++++++++++++++++++++ > > include/linux/of_pci.h | 3 +++ > > 2 files changed, 33 insertions(+) > > > > diff --git a/drivers/of/of_pci.c b/drivers/of/of_pci.c > > index 5751dc5..a4e29ff 100644 > > --- a/drivers/of/of_pci.c > > +++ b/drivers/of/of_pci.c > > @@ -118,6 +118,36 @@ int of_get_pci_domain_nr(struct device_node *node) > > EXPORT_SYMBOL_GPL(of_get_pci_domain_nr); > > > > /** > > + * of_pci_check_probe_only - Setup probe only mode if linux,pci-probe-only > > + * is present and valid > > + * > > + * @node: device tree node that may contain the property (usually "chosen") > > + * > > + */ > > +void of_pci_check_probe_only(struct device_node *node) > > +{ > > + const int *prop; > > + int len; > > + > > + if (!node) > > + return; > > + > > + prop = of_get_property(node, "linux,pci-probe-only", &len); > > It is preferred to use of_property_read_u32 to avoid just these types > of problems. I don't know enough OF to really understand this, but I infer that this is a suggestion for improving the patch. Should I be waiting for a v3 series? Bjorn -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 02/09/15 23:23, Bjorn Helgaas wrote: > On Fri, Aug 14, 2015 at 04:08:10PM -0500, Rob Herring wrote: >> On Fri, Aug 14, 2015 at 11:19 AM, Marc Zyngier <marc.zyngier@arm.com> wrote: >>> Both pci-host-generic and Pseries parse the "linux,pci-probe-only" >>> to engage the PCI_PROBE_ONLY mode, and both have a subtle bug that >>> can be triggered if the property has no parameter. >> >> Humm, I bet we could break a lot of machines if we fixed the core code >> to properly make pp->value NULL when there is no value. >> >>> Provide a generic implementation that can be used by both. >>> >>> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> >>> --- >>> drivers/of/of_pci.c | 30 ++++++++++++++++++++++++++++++ >>> include/linux/of_pci.h | 3 +++ >>> 2 files changed, 33 insertions(+) >>> >>> diff --git a/drivers/of/of_pci.c b/drivers/of/of_pci.c >>> index 5751dc5..a4e29ff 100644 >>> --- a/drivers/of/of_pci.c >>> +++ b/drivers/of/of_pci.c >>> @@ -118,6 +118,36 @@ int of_get_pci_domain_nr(struct device_node *node) >>> EXPORT_SYMBOL_GPL(of_get_pci_domain_nr); >>> >>> /** >>> + * of_pci_check_probe_only - Setup probe only mode if linux,pci-probe-only >>> + * is present and valid >>> + * >>> + * @node: device tree node that may contain the property (usually "chosen") >>> + * >>> + */ >>> +void of_pci_check_probe_only(struct device_node *node) >>> +{ >>> + const int *prop; >>> + int len; >>> + >>> + if (!node) >>> + return; >>> + >>> + prop = of_get_property(node, "linux,pci-probe-only", &len); >> >> It is preferred to use of_property_read_u32 to avoid just these types >> of problems. > > I don't know enough OF to really understand this, but I infer that > this is a suggestion for improving the patch. Should I be waiting for > a v3 series? Yes, I'll post an update very shortly. Thanks for reminding me! M.
diff --git a/drivers/of/of_pci.c b/drivers/of/of_pci.c index 5751dc5..a4e29ff 100644 --- a/drivers/of/of_pci.c +++ b/drivers/of/of_pci.c @@ -118,6 +118,36 @@ int of_get_pci_domain_nr(struct device_node *node) EXPORT_SYMBOL_GPL(of_get_pci_domain_nr); /** + * of_pci_check_probe_only - Setup probe only mode if linux,pci-probe-only + * is present and valid + * + * @node: device tree node that may contain the property (usually "chosen") + * + */ +void of_pci_check_probe_only(struct device_node *node) +{ + const int *prop; + int len; + + if (!node) + return; + + prop = of_get_property(node, "linux,pci-probe-only", &len); + if (prop) { + if (!len) { + pr_warn("linux,pci-probe-only set without value, ignoring\n"); + return; + } + + if (be32_to_cpup(prop)) + pci_add_flags(PCI_PROBE_ONLY); + else + pci_clear_flags(PCI_PROBE_ONLY); + } +} +EXPORT_SYMBOL_GPL(of_pci_check_probe_only); + +/** * of_pci_dma_configure - Setup DMA configuration * @dev: ptr to pci_dev struct of the PCI device * diff --git a/include/linux/of_pci.h b/include/linux/of_pci.h index 29fd3fe..4c0a617 100644 --- a/include/linux/of_pci.h +++ b/include/linux/of_pci.h @@ -17,6 +17,7 @@ int of_irq_parse_and_map_pci(const struct pci_dev *dev, u8 slot, u8 pin); int of_pci_parse_bus_range(struct device_node *node, struct resource *res); int of_get_pci_domain_nr(struct device_node *node); void of_pci_dma_configure(struct pci_dev *pci_dev); +void of_pci_check_probe_only(struct device_node *node); #else static inline int of_irq_parse_pci(const struct pci_dev *pdev, struct of_phandle_args *out_irq) { @@ -53,6 +54,8 @@ of_get_pci_domain_nr(struct device_node *node) } static inline void of_pci_dma_configure(struct pci_dev *pci_dev) { } + +static inline void of_pci_check_probe_only(struct device_node *node) { } #endif #if defined(CONFIG_OF_ADDRESS)
Both pci-host-generic and Pseries parse the "linux,pci-probe-only" to engage the PCI_PROBE_ONLY mode, and both have a subtle bug that can be triggered if the property has no parameter. Provide a generic implementation that can be used by both. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> --- drivers/of/of_pci.c | 30 ++++++++++++++++++++++++++++++ include/linux/of_pci.h | 3 +++ 2 files changed, 33 insertions(+)