Re: [PATCH] kexec: force x86_64 arches to boot kdump kernels on boot cpu

Neil Horman
2007-12-11T18:25:50Z

On Tue, Dec 11, 2007 at 08:29:20AM -0700, Eric W. Biederman wrote:
> Neil Horman <nhorman@tuxdriver.com> writes:
>
> > On Mon, Dec 10, 2007 at 09:48:11PM -0700, Eric W. Biederman wrote:
> >> Neil Horman <nhorman@tuxdriver.com> writes:
>
> Ok. I just looked at read_pci_config. It doesn't do the right thing for
> a non-aligned 32bit access. (Not that I am convinced there is a right
> thing we can do). Please make this read_pci_config_16 instead
> and you won't need the shift.
>
> Either that or as I earlier suggested just do a 32bit read from offset 0
> and use shifts and masks to get vendor and device fields.
>

The former seems like a reasonable solution to me. Corrected in this updated
patch.

> You almost got YH's comment. You need return 2 for the old functions
> so we don't try and apply a per chipset fixup for every device in
> the system.
>
> I'm actually inclined to remove the return magic and just do something
> like:
> static fix_applied;
> if (fix_applied++)
> return;
> In those functions that should be called only once.
>

I like the latter approach better. It seems less convoluted to me.

New patch attached.

Thanks & Regards
Neil

Signed-off-by: Neil Horman <nhorman@tuxdriver.com>

early-quirks.c | 90 +++++++++++++++++++++++++++++++++++++++++++--------------
1 file changed, 69 insertions(+), 21 deletions(-)

diff --git a/arch/x86/kernel/early-quirks.c b/arch/x86/kernel/early-quirks.c
index 88bb83e..f307285 100644
--- a/arch/x86/kernel/early-quirks.c
+++ b/arch/x86/kernel/early-quirks.c
@@ -21,8 +21,13 @@
#include <asm/gart.h>
#endif

-static void __init via_bugs(void)
+static void __init via_bugs(int num, int slot, int func)
{
+ static int fix_applied = 0;
+
+ if (fix_applied++)
+ return;
+
#ifdef CONFIG_GART_IOMMU
if ((end_pfn > MAX_DMA32_PFN || force_iommu) &&
!gart_iommu_aperture_allowed) {
@@ -44,8 +49,36 @@ static int __init nvidia_hpet_check(struct acpi_table_header *header)
#endif /* CONFIG_X86_IO_APIC */
#endif /* CONFIG_ACPI */

-static void __init nvidia_bugs(void)
+static void __init fix_hypertransport_config(int num, int slot, int func)
{
+ u32 htcfg;
+ /*
+ *we found a hypertransport bus
+ *make sure that are broadcasting
+ *interrupts to all cpus on the ht bus
+ *if we're using extended apic ids
+ */
+ htcfg = read_pci_config(num, slot, func, 0x68);
+ if (htcfg & (1 << 18)) {
+ printk(KERN_INFO "Detected use of extended apic ids on hypertransport bus\n");
+ if ((htcfg & (1 << 17)) == 0) {
+ printk(KERN_INFO "Enabling hypertransport extended apic interrupt broadcast\n");
+ printk(KERN_INFO "Note this is a bios bug, please contact your hw vendor\n");
+ htcfg |= (1 << 17);
+ write_pci_config(num, slot, func, 0x68, htcfg);
+ }
+ }
+
+
+}
+
+static void __init nvidia_bugs(int num, int slot, int func)
+{
+ static int fix_applied = 0;
+
+ if (fix_applied++)
+ return;
+
#ifdef CONFIG_ACPI
#ifdef CONFIG_X86_IO_APIC
/*
@@ -72,8 +105,13 @@ static void __init nvidia_bugs(void)

}

-static void __init ati_bugs(void)
+static void __init ati_bugs(int num, int slot, int func)
{
+ static int fix_applied = 0;
+
+ if (fix_applied++)
+ return;
+
#ifdef CONFIG_X86_IO_APIC
if (timer_over_8254 == 1) {
timer_over_8254 = 0;
@@ -84,14 +122,18 @@ static void __init ati_bugs(void)
}

struct chipset {
- u16 vendor;
- void (*f)(void);
+ u32 vendor;
+ u32 device;
+ u32 class;
+ u32 class_mask;
+ void (*f)(int num, int slot, int func);
};

static struct chipset early_qrk[] __initdata = {
- { PCI_VENDOR_ID_NVIDIA, nvidia_bugs },
- { PCI_VENDOR_ID_VIA, via_bugs },
- { PCI_VENDOR_ID_ATI, ati_bugs },
+ { PCI_VENDOR_ID_NVIDIA, PCI_ANY_ID, PCI_CLASS_BRIDGE_PCI, PCI_ANY_ID, nvidia_bugs },
+ { PCI_VENDOR_ID_VIA, PCI_ANY_ID, PCI_CLASS_BRIDGE_PCI, PCI_ANY_ID, via_bugs },
+ { PCI_VENDOR_ID_ATI, PCI_ANY_ID, PCI_CLASS_BRIDGE_PCI, PCI_ANY_ID, ati_bugs },
+ { PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_K8_NB, PCI_CLASS_BRIDGE_HOST, PCI_ANY_ID, fix_hypertransport_config },
{}
};

@@ -106,27 +148,33 @@ void __init early_quirks(void)
for (num = 0; num < 32; num++) {
for (slot = 0; slot < 32; slot++) {
for (func = 0; func < 8; func++) {
- u32 class;
- u32 vendor;
+ u16 class;
+ u16 vendor;
+ u16 device;
u8 type;
int i;
- class = read_pci_config(num,slot,func,
+
+ class = read_pci_config_16(num,slot,func,
PCI_CLASS_REVISION);
- if (class == 0xffffffff)
+ if (class == 0xffff)
break;

- if ((class >> 16) != PCI_CLASS_BRIDGE_PCI)
- continue;
-
- vendor = read_pci_config(num, slot, func,
+ vendor = read_pci_config_16(num, slot, func,
PCI_VENDOR_ID);
- vendor &= 0xffff;

- for (i = 0; early_qrk[i].f; i++)
- if (early_qrk[i].vendor == vendor) {
- early_qrk[i].f();
- return;
+ device = read_pci_config_16(num, slot, func,
+ PCI_DEVICE_ID);
+
+ for(i=0;early_qrk[i].f != NULL;i++) {
+ if (((early_qrk[i].vendor == PCI_ANY_ID) ||
+ (early_qrk[i].vendor == vendor)) &&
+ ((early_qrk[i].device == PCI_ANY_ID) ||
+ (early_qrk[i].device == device)) &&
+ (!((early_qrk[i].class ^ class) &
+ early_qrk[i].class_mask))) {
+ early_qrk[i].f(num, slot, func);
}
+ }

type = read_pci_config_byte(num, slot, func,
PCI_HEADER_TYPE);