path: root/arch/parisc/configs/c8000_defconfig
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authorJohn David Anglin <>2013-07-23 12:27:52 -0400
committerHelge Deller <>2013-07-31 23:41:47 +0200
commit50861f5a02dbf939c27d35a26c472885e2844188 (patch)
treea039ce8beb259f6d205493c7f6380f2b52dbca1a /arch/parisc/configs/c8000_defconfig
parent06693f305e60202d2795a10bee7fb7da23bc2acc (diff)
parisc: Fix cache routines to ignore vma's with an invalid pfn
The parisc architecture does not have a pte special bit. As a result, special mappings are handled with the VM_PFNMAP and VM_MIXEDMAP flags. VM_MIXEDMAP mappings may or may not have a "struct page" backing. When pfn_valid() is false, there is no "struct page" backing. Otherwise, they are treated as normal pages. The FireGL driver uses the VM_MIXEDMAP without a backing "struct page". This treatment caused a panic due to a TLB data miss in update_mmu_cache. This appeared to be in the code generated for page_address(). We were in fact using a very circular bit of code to determine the physical address of the PFN in various cache routines. This wasn't valid when there was no "struct page" backing. The needed address can in fact be determined simply from the PFN itself without using the "struct page". The attached patch updates update_mmu_cache(), flush_cache_mm(), flush_cache_range() and flush_cache_page() to check pfn_valid() and to directly compute the PFN physical and virtual addresses. Signed-off-by: John David Anglin <> Cc: <> # 3.10 Signed-off-by: Helge Deller <>
Diffstat (limited to 'arch/parisc/configs/c8000_defconfig')
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