Re: Regression with commit f9cde5f in 2.6.30-gitX

Yinghai Lu
2009-06-24T22:53:37Z

[-- Attachment #1: Type: text/plain, Size: 804 bytes --]

On Wed, Jun 24, 2009 at 3:11 PM, Yinghai Lu<yhlu.kernel@gmail.com> wrote:
> On Wed, Jun 24, 2009 at 3:04 PM, Larry Finger<Larry.Finger@lwfinger.net> wrote:
>> Yinghai Lu wrote:
>> node 0 link 0: mmio [a0000, bffff]
>> node 0 link 0: mmio [c0000000, dfffffff]
>> node 0 link 0: mmio [e0000000, efffffff]
>> node 0 link 0: mmio [f0000000, fe0bffff]
>> bus: [00,ff] on node 0 link 0
>> bus: 00 index 0 io port: [0, ffff]
>> bus: 00 index 1 mmio: [a0000, bffff]
>> bus: 00 index 2 mmio: [c0000000, fcffffffff]
>
> that is read from pci config.
>
> and only one HT chain is there. so there is no point to use _CRS for them.
>
> please let me check if we could could have patch to deselect that.
>

please try the attached patches.

applying sequence:
fix_crs.patch
use_pci_crs_early.patch

only_one.patch

YH

[-- Attachment #2: fix_crs.patch --]
[-- Type: text/x-diff, Size: 1982 bytes --]

[PATCH] x86/pci: fix boundary checking

don't touch info->res_num if we are out of space

Signed-off-by: Yinghai Lu <yinghai@kernel.org>

---
arch/x86/pci/acpi.c | 27 +++++++++++++++------------
1 file changed, 15 insertions(+), 12 deletions(-)

Index: linux-2.6/arch/x86/pci/acpi.c
===================================================================
--- linux-2.6.orig/arch/x86/pci/acpi.c
+++ linux-2.6/arch/x86/pci/acpi.c
@@ -68,6 +68,10 @@ setup_resource(struct acpi_resource *acp
unsigned long flags;
struct resource *root;
int max_root_bus_resources = PCI_BUS_NUM_RESOURCES;
+ u64 start, end;
+
+ if (bus_has_transparent_bridge(info->bus))
+ max_root_bus_resources -= 3;

status = resource_to_addr(acpi_res, &addr);
if (!ACPI_SUCCESS(status))
@@ -84,25 +88,24 @@ setup_resource(struct acpi_resource *acp
} else
return AE_OK;

- res = &info->res[info->res_num];
- res->name = info->name;
- res->flags = flags;
- res->start = addr.minimum + addr.translation_offset;
- res->end = res->start + addr.address_length - 1;
- res->child = NULL;
-
- if (bus_has_transparent_bridge(info->bus))
- max_root_bus_resources -= 3;
+ start = addr.minimum + addr.translation_offset;
+ end = start + addr.address_length - 1;
if (info->res_num >= max_root_bus_resources) {
printk(KERN_WARNING "PCI: Failed to allocate 0x%lx-0x%lx "
"from %s for %s due to _CRS returning more than "
- "%d resource descriptors\n", (unsigned long) res->start,
- (unsigned long) res->end, root->name, info->name,
+ "%d resource descriptors\n", (unsigned long) start,
+ (unsigned long) end, root->name, info->name,
max_root_bus_resources);
- info->res_num++;
return AE_OK;
}

+ res = &info->res[info->res_num];
+ res->name = info->name;
+ res->flags = flags;
+ res->start = start;
+ res->end = end;
+ res->child = NULL;
+
if (insert_resource(root, res)) {
printk(KERN_ERR "PCI: Failed to allocate 0x%lx-0x%lx "
"from %s for %s\n", (unsigned long) res->start,

[-- Attachment #3: use_pci_crs_early.patch --]
[-- Type: text/x-diff, Size: 2982 bytes --]

[PATCH] x86/pci: get root CRS before scan childs -v2

so we could remove adjust_transparent_bridge_resources..

and give x86_pci_root_bus_res_quirks chance when _CRS is not used or
not there.

v2: add print out if pci conf reading for res is used for root

Signed-off-by: Yinghai Lu <yinghai@kernel.org>

---
arch/x86/pci/acpi.c | 32 +++++++++-----------------------
arch/x86/pci/amd_bus.c | 8 ++++++--
2 files changed, 15 insertions(+), 25 deletions(-)

Index: linux-2.6/arch/x86/pci/acpi.c
===================================================================
--- linux-2.6.orig/arch/x86/pci/acpi.c
+++ linux-2.6/arch/x86/pci/acpi.c
@@ -118,23 +118,6 @@ setup_resource(struct acpi_resource *acp
}

static void
-adjust_transparent_bridge_resources(struct pci_bus *bus)
-{
- struct pci_dev *dev;
-
- list_for_each_entry(dev, &bus->devices, bus_list) {
- int i;
- u16 class = dev->class >> 8;
-
- if (class == PCI_CLASS_BRIDGE_PCI && dev->transparent) {
- for(i = 3; i < PCI_BUS_NUM_RESOURCES; i++)
- dev->subordinate->resource[i] =
- dev->bus->resource[i - 3];
- }
- }
-}
-
-static void
get_current_resources(struct acpi_device *device, int busnum,
int domain, struct pci_bus *bus)
{
@@ -161,8 +144,6 @@ get_current_resources(struct acpi_device
info.res_num = 0;
acpi_walk_resources(device->handle, METHOD_NAME__CRS, setup_resource,
&info);
- if (info.res_num)
- adjust_transparent_bridge_resources(bus);

return;

@@ -225,8 +206,15 @@ struct pci_bus * __devinit pci_acpi_scan
*/
memcpy(bus->sysdata, sd, sizeof(*sd));
kfree(sd);
- } else
- bus = pci_scan_bus_parented(NULL, busnum, &pci_root_ops, sd);
+ } else {
+ bus = pci_create_bus(NULL, busnum, &pci_root_ops, sd);
+ if (bus) {
+ if (!(pci_probe & PCI_NO_ROOT_CRS))
+ get_current_resources(device, busnum, domain,
+ bus);
+ bus->subordinate = pci_scan_child_bus(bus);
+ }
+ }

if (!bus)
kfree(sd);
@@ -241,8 +229,6 @@ struct pci_bus * __devinit pci_acpi_scan
#endif
}

- if (bus && !(pci_probe & PCI_NO_ROOT_CRS))
- get_current_resources(device, busnum, domain, bus);
return bus;
}

Index: linux-2.6/arch/x86/pci/amd_bus.c
===================================================================
--- linux-2.6.orig/arch/x86/pci/amd_bus.c
+++ linux-2.6/arch/x86/pci/amd_bus.c
@@ -100,8 +100,9 @@ void x86_pci_root_bus_res_quirks(struct
int j;
struct pci_root_info *info;

- /* don't go for it if _CRS is used */
- if (!(pci_probe & PCI_NO_ROOT_CRS))
+ /* don't go for it if _CRS is used already */
+ if (b->resource[0] != &ioport_resource ||
+ b->resource[1] != &iomem_resource)
return;

/* if only one root bus, don't need to anything */
@@ -116,6 +117,9 @@ void x86_pci_root_bus_res_quirks(struct
if (i == pci_root_num)
return;

+ printk(KERN_DEBUG "PCI: peer root bus %02x res updated from pci conf\n",
+ b->number);
+
info = &pci_root_info[i];
for (j = 0; j < info->res_num; j++) {
struct resource *res;

[-- Attachment #4: only_one.patch --]
[-- Type: text/x-diff, Size: 650 bytes --]

[PATCH] x86/pci: don't use crs for root if we only have one root bus

for AMD system, when only one PCI root, just set PCI_NO_ROOT_CRS for it

Signed-off-by: Yinghai Lu <yinghai@kernel.org>

---
arch/x86/pci/amd_bus.c | 4 ++++
1 file changed, 4 insertions(+)

Index: linux-2.6/arch/x86/pci/amd_bus.c
===================================================================
--- linux-2.6.orig/arch/x86/pci/amd_bus.c
+++ linux-2.6/arch/x86/pci/amd_bus.c
@@ -561,6 +561,10 @@ static int __init early_fill_mp_bus_info
}
}

+ /* don't use _CRS if we only have one root */
+ if (pci_root_num <= 1)
+ pci_probe |= PCI_NO_ROOT_CRS;
+
return 0;
}