Re: Error: freeing invalid memtype

[Kevin Winchester <kjwinchester@gmail.com>]

Pallipadi, Venkatesh wrote:
> On Sat, Mar 21, 2009 at 04:05:48PM -0700, Kevin Winchester wrote:
>> Pallipadi, Venkatesh wrote:
>>> Kevin,
>>>
>>> Can you please send me the output of
>>> # cat /debug/x86/pat_memtype_list
>>>
>>> (with debugfs mounted at /debug) as soon as you login into X and also
>>> when you start seeing these errors with etracer and glxinfo.
>>>
>> Here is the output before attempting to run glxinfo:
>> : :
>> : :
>>
>> Does that help track down the problem?  I am about to try disabling PAT
>> in my config to see if that fixes things.
>>
> 
> Can you please try the patch below and let me whether it helps.
> 
> Thanks,
> Venki
> 
> x86, PAT: Change vma prot in pci_mmap to reflect inherited prot
>     
> While looking at the issue in the thread
> http://marc.info/?l=dri-devel&m=123606627824556&w=2
> noticed a bug in pci PAT code and memory type setting.
>     
> pci mmap code did not set the proper protection in vma, when it
> inherited protection in reserve_memtype. This bug only affects
> the case where there exists a WC mapping before X does an mmap
> with /proc or /sys pci interface. This will cause X userlevel
> mmap from /proc or /sysfs to fail on fork.
>     
> Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
> Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
> 
> diff --git a/arch/x86/pci/i386.c b/arch/x86/pci/i386.c
> index 5ead808..f234a37 100644
> --- a/arch/x86/pci/i386.c
> +++ b/arch/x86/pci/i386.c
> @@ -319,6 +319,9 @@ int pci_mmap_page_range(struct pci_dev *dev, struct vm_area_struct *vma,
>  			return -EINVAL;
>  		}
>  		flags = new_flags;
> +		vma->vm_page_prot = __pgprot(
> +			(pgprot_val(vma->vm_page_prot) & ~_PAGE_CACHE_MASK) |
> +			flags);
>  	}
>  
>  	if (((vma->vm_pgoff < max_low_pfn_mapped) ||

This patch fixes the problem for me - no more errors in my dmesg.  I suppose that I also
did update to the latest mainline as well, so it could possibly have been some other patch
instead.  If you think there is a big risk of that, let me know and I'll repeat the test
and make sure that this patch is the only difference.

Thanks,

-- 
Kevin Winchester