lkml.org 
[lkml]   [2009]   [Aug]   [17]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
From
SubjectRe: [regression, bisected] fails to boot on Dell Optiplex 760 with VT-d enabled
* Faidon Liambotis (paravoid@debian.org) wrote:
> I am experiencin a bug on an Dell Optiplex 760 with a configuration that
> has an Intel Core2 Q9550 CPU and with an up-to-date BIOS, version A03.
>
> When "VT for Direct I/O" is enabled in the BIOS, v2.6.30 boots and works
> perfectly, while v2.6.31-rc1..rc6 fail (both of them x86-64).

AFAIK, this platform is broken when VT-d is enabled.
Can you add this patch to a broken kernel and retest?
Please boot with 'debug' on the kernel command line.

drivers/pci/dmar.c | 19 ++++++++++++-------
1 files changed, 12 insertions(+), 7 deletions(-)
diff --git a/drivers/pci/dmar.c b/drivers/pci/dmar.c
index 7b287cb..40f497b 100644
--- a/drivers/pci/dmar.c
+++ b/drivers/pci/dmar.c
@@ -631,6 +631,18 @@ int alloc_iommu(struct dmar_drhd_unit *drhd)
}
iommu->cap = dmar_readq(iommu->reg + DMAR_CAP_REG);
iommu->ecap = dmar_readq(iommu->reg + DMAR_ECAP_REG);
+ ver = readl(iommu->reg + DMAR_VER_REG);
+ printk(KERN_DEBUG "IOMMU %llx: ver %d:%d cap %llx ecap %llx\n",
+ (unsigned long long)drhd->reg_base_addr,
+ DMAR_VER_MAJOR(ver), DMAR_VER_MINOR(ver),
+ (unsigned long long)iommu->cap,
+ (unsigned long long)iommu->ecap);
+
+ if (ver == (u32)-1 || iommu->cap == (u64)-1 || iommu->ecap == (u64)-1) {
+ printk(KERN_ERR "IOMMU: BIOS or hardware problem, disabling "
+ "VT-d\n");
+ goto error;
+ }

#ifdef CONFIG_DMAR
agaw = iommu_calculate_agaw(iommu);
@@ -664,13 +676,6 @@ int alloc_iommu(struct dmar_drhd_unit *drhd)
}
}

- ver = readl(iommu->reg + DMAR_VER_REG);
- pr_debug("IOMMU %llx: ver %d:%d cap %llx ecap %llx\n",
- (unsigned long long)drhd->reg_base_addr,
- DMAR_VER_MAJOR(ver), DMAR_VER_MINOR(ver),
- (unsigned long long)iommu->cap,
- (unsigned long long)iommu->ecap);
-
spin_lock_init(&iommu->register_lock);

drhd->iommu = iommu;

\
 
 \ /
  Last update: 2009-08-18 01:15    [from the cache]
©2003-2014 Jasper Spaans. Advertise on this site