From: Arno Geissel <jgeissel@gmx•net>
To: linuxppc-embedded@ozlabs•org
Subject: Re: Bigphysarea vs. kernel 2.4.32 and PPC405GPr
Date: Mon, 15 May 2006 08:35:48 +0200 [thread overview]
Message-ID: <200605150835.48745.jgeissel@gmx.net> (raw)
In-Reply-To: <e435rv$62q$1@sea.gmane.org>
Try
rc = remap_page_range(vma->vm_start,
virt_to_phys(heap_map_base),
npages*PAGE_SIZE,
vma->vm_page_prot);
Arno
> I'm trying to use the bigphysarea patch to help me allocate big
> physical chunks of memory for use by some custom embedded devices.
> I've applied the bigphysarea-2.4.20 patch and built, no trouble,
> and I've got it to config for my PPC. I can see at boot time that
> the bigphysarea is getting its pages.
>
> I'm trying to use a mmap call to the driver to map a chunk of this
> memory into the process. The mmap for the driver has this:
>
> pgprot_val(vma->vm_page_prot) |= _PAGE_NO_CACHE;
> vma->vm_flags |= VM_RESERVED;
>
> npages = (vma->vm_end - vma->vm_start) / PAGE_SIZE;
> heap_map_base = bigphysarea_alloc_pages(npages, 1, GFP_KERNEL);
>
> printk("XXXX Map base=%p, %ld pages\n", heap_map_base, npages);
>
> rc = remap_page_range(vma->vm_start,
> (unsigned long)heap_map_base,
> npages*PAGE_SIZE,
> vma->vm_page_prot);
>
> The mmap returns without an error, but any access to the mapped
> region gets me an immediate "Oops: machine check, sig: 7". I don't
> see it. Where is the stupid mistake that I'm invariably making?
next prev parent reply other threads:[~2006-05-15 6:35 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2006-05-12 23:31 Bigphysarea vs. kernel 2.4.32 and PPC405GPr Stephen Williams
2006-05-15 6:35 ` Arno Geissel [this message]
2006-05-17 17:07 ` Stephen Williams
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