[PATCH] drivers: pci: initialise class to 0 before reading
Otherwise, uninitialised memory from the upper 32 bits can end up in find_id.class, and this causes bugs later when looking for a driver for the class.
Signed-off-by: Hugh Cole-Baker sigmaris@gmail.com --- drivers/pci/pci-uclass.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/pci/pci-uclass.c b/drivers/pci/pci-uclass.c index fab20fc60e..c28a1cc363 100644 --- a/drivers/pci/pci-uclass.c +++ b/drivers/pci/pci-uclass.c @@ -773,7 +773,7 @@ int pci_bind_bus_devices(struct udevice *bus) bdf += PCI_BDF(0, 0, 1)) { struct pci_child_platdata *pplat; struct udevice *dev; - ulong class; + ulong class = 0;
if (!PCI_FUNC(bdf)) found_multi = false;
On Wed, Jan 1, 2020 at 7:15 PM Hugh Cole-Baker sigmaris@gmail.com wrote:
Otherwise, uninitialised memory from the upper 32 bits can end up in find_id.class, and this causes bugs later when looking for a driver for the class.
Signed-off-by: Hugh Cole-Baker sigmaris@gmail.com
drivers/pci/pci-uclass.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/pci/pci-uclass.c b/drivers/pci/pci-uclass.c index fab20fc60e..c28a1cc363 100644 --- a/drivers/pci/pci-uclass.c +++ b/drivers/pci/pci-uclass.c @@ -773,7 +773,7 @@ int pci_bind_bus_devices(struct udevice *bus) bdf += PCI_BDF(0, 0, 1)) { struct pci_child_platdata *pplat; struct udevice *dev;
ulong class;
ulong class = 0; if (!PCI_FUNC(bdf)) found_multi = false;--
I see class is initialized in the call to:
pci_bus_read_config(bus, bdf, PCI_CLASS_REVISION, &class, PCI_SIZE_32); class >>= 8;
Regards, Bin
Hi Bin,
On 1 Jan 2020, at 13:25, Bin Meng bmeng.cn@gmail.com wrote:
On Wed, Jan 1, 2020 at 7:15 PM Hugh Cole-Baker sigmaris@gmail.com wrote:
Otherwise, uninitialised memory from the upper 32 bits can end up in find_id.class, and this causes bugs later when looking for a driver for the class.
Signed-off-by: Hugh Cole-Baker sigmaris@gmail.com
drivers/pci/pci-uclass.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/pci/pci-uclass.c b/drivers/pci/pci-uclass.c index fab20fc60e..c28a1cc363 100644 --- a/drivers/pci/pci-uclass.c +++ b/drivers/pci/pci-uclass.c @@ -773,7 +773,7 @@ int pci_bind_bus_devices(struct udevice *bus) bdf += PCI_BDF(0, 0, 1)) { struct pci_child_platdata *pplat; struct udevice *dev;
ulong class;
ulong class = 0; if (!PCI_FUNC(bdf)) found_multi = false;--
I see class is initialized in the call to:
pci_bus_read_config(bus, bdf, PCI_CLASS_REVISION, &class, PCI_SIZE_32); class >>= 8;
Maybe the driver I'm working with is doing its read_config wrongly? I'm trying to use this Rockchip PCIe driver [1] with upstream u-boot. The driver casts &class to u32*, uses readl() and only sets the lower 32 bits. I was assuming that this was normal for a read of PCI_SIZE_32. However, looking at some of the other drivers, it seems like it should be using pci_conv_32_to_size() instead?
[1] https://github.com/radxa/u-boot/blob/rk3399-pie-gms-express-baseline/drivers...
Thanks, Hugh
Regards, Bin
Hi Hugh,
On Wed, Jan 1, 2020 at 9:50 PM Hugh Cole-Baker sigmaris@gmail.com wrote:
Hi Bin,
On 1 Jan 2020, at 13:25, Bin Meng bmeng.cn@gmail.com wrote:
On Wed, Jan 1, 2020 at 7:15 PM Hugh Cole-Baker sigmaris@gmail.com wrote:
Otherwise, uninitialised memory from the upper 32 bits can end up in find_id.class, and this causes bugs later when looking for a driver for the class.
Signed-off-by: Hugh Cole-Baker sigmaris@gmail.com
drivers/pci/pci-uclass.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/pci/pci-uclass.c b/drivers/pci/pci-uclass.c index fab20fc60e..c28a1cc363 100644 --- a/drivers/pci/pci-uclass.c +++ b/drivers/pci/pci-uclass.c @@ -773,7 +773,7 @@ int pci_bind_bus_devices(struct udevice *bus) bdf += PCI_BDF(0, 0, 1)) { struct pci_child_platdata *pplat; struct udevice *dev;
ulong class;
ulong class = 0; if (!PCI_FUNC(bdf)) found_multi = false;--
I see class is initialized in the call to:
pci_bus_read_config(bus, bdf, PCI_CLASS_REVISION, &class, PCI_SIZE_32); class >>= 8;
Maybe the driver I'm working with is doing its read_config wrongly? I'm trying to use this Rockchip PCIe driver [1] with upstream u-boot. The driver casts &class to u32*, uses readl() and only sets the lower 32 bits. I was assuming that this was normal for a read of PCI_SIZE_32. However, looking at some of the other drivers, it seems like it should be using pci_conv_32_to_size() instead?
The bug should be that
https://github.com/radxa/u-boot/blob/rk3399-pie-gms-express-baseline/drivers...
u32 *val should be declared as ulong *val.
[1] https://github.com/radxa/u-boot/blob/rk3399-pie-gms-express-baseline/drivers...
Regards, Bin
participants (2)
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Bin Meng -
Hugh Cole-Baker