Re: [PATCH v4 0/4] PCI: arm64/powerpc: Fix parsing of linux,pci-probe-only

From: Marc Zyngier
Date: Thu Sep 17 2015 - 13:17:48 EST


On 17/09/15 16:30, Bjorn Helgaas wrote:
> On Fri, Sep 04, 2015 at 05:50:07PM +0100, Marc Zyngier wrote:
>> The pci-host-generic driver parses the linux,pci-probe-only property,
>> and assumes that it will have a boolean parameter.
>>
>> Turns out that the Seattle DTS file has a naked "linux,pci-probe-only"
>> property, which leads to the driver dereferencing some unsuspecting
>> memory location. Nothing really bad happens (we end up reading some
>> other bit of DT, fortunately), but that not a reason to keep it this
>> way. Turns out that the Pseries code (where this code was lifted from)
>> may suffer from the same issue.
>>
>> The first patch introduces a common (and fixed) version of that check
>> that can be used by drivers and architectures that require it. The two
>> following patches change the pci-host-generic driver and the powerpc
>> code to use it.
>>
>> Finally, the bad property is removed from the Seatle DTS, because it
>> is simply not necessary (it actually prevents me from using SR-IOV,
>> which otherwise runs fine without the probe-only thing).
>>
>> This has been tested on the offending Seattle board.
>>
>> * From v3:
>> - Restrict the property lookup to /chosen (Rob)
>> - Acked-by on patch #4 from Suravee
>> - I swear this is the last time I rework these patches! ;-)
>>
>> * From v2:
>> - Use of_property_read_u32 to safely read the property (Rob)
>> - Add a log message to indicate when we enable probe-only
>> (probably quite useful for debugging)
>>
>> * From v1:
>> - Consolidate the parsing in of_pci.c (Bjorn)
>>
>> Marc Zyngier (4):
>> of/pci: Add of_pci_check_probe_only to parse "linux,pci-probe-only"
>> PCI: pci-host-generic: Fix lookup of linux,pci-probe-only property
>> powerpc: PCI: Fix lookup of linux,pci-probe-only property
>> arm64: dts: Drop linux,pci-probe-only from the Seattle DTS
>>
>> arch/arm64/boot/dts/amd/amd-overdrive.dts | 1 -
>> arch/powerpc/platforms/pseries/setup.c | 14 ++------------
>> drivers/of/of_pci.c | 28 ++++++++++++++++++++++++++++
>> drivers/pci/host/pci-host-generic.c | 9 +--------
>> include/linux/of_pci.h | 3 +++
>> 5 files changed, 34 insertions(+), 21 deletions(-)
>
> Applied with the comment tweak and acks to pci/host-generic for v4.4,
> thanks!

Turns out that the 01.org infrastructure has picked up on a compilation
bug with randconfig. The following patch seems to fix it and should be
applied on the first patch:

diff --git a/drivers/of/of_pci.c b/drivers/of/of_pci.c
index 485d625..2da5abc 100644
--- a/drivers/of/of_pci.c
+++ b/drivers/of/of_pci.c
@@ -6,6 +6,8 @@
#include <linux/of_pci.h>
#include <linux/slab.h>

+#include <asm-generic/pci-bridge.h>
+
static inline int __of_pci_pci_compare(struct device_node *node,
unsigned int data)
{

Sorry for the annoyance.

M.
--
Jazz is not dead. It just smells funny...
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/