iommu/vt-d: Handle 36bit addressing for x86-32

Beware that the address size for x86-32 may exceed unsigned long.

[ 0.368971] UBSAN: shift-out-of-bounds in drivers/iommu/intel/iommu.c:128:14
[ 0.369055] shift exponent 36 is too large for 32-bit type 'long unsigned int'

If we don't handle the wide addresses, the pages are mismapped and the
device read/writes go astray, detected as DMAR faults and leading to
device failure. The behaviour changed (from working to broken) in commit
fa954e683178 ("iommu/vt-d: Delegate the dma domain to upper layer"), but
the error looks older.

Fixes: fa954e683178 ("iommu/vt-d: Delegate the dma domain to upper layer")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Acked-by: Lu Baolu <baolu.lu@linux.intel.com>
Cc: James Sewart <jamessewart@arista.com>
Cc: Lu Baolu <baolu.lu@linux.intel.com>
Cc: Joerg Roedel <jroedel@suse.de>
Cc: <stable@vger.kernel.org> # v5.3+
Link: https://lore.kernel.org/r/20200822160209.28512-1-chris@chris-wilson.co.uk
Signed-off-by: Joerg Roedel <jroedel@suse.de>

authored by

Chris Wilson and committed by
Joerg Roedel
29aaebbc 2822e582

+7 -7
+7 -7
drivers/iommu/intel/iommu.c
··· 123 return (level - 1) * LEVEL_STRIDE; 124 } 125 126 - static inline int pfn_level_offset(unsigned long pfn, int level) 127 { 128 return (pfn >> level_to_offset_bits(level)) & LEVEL_MASK; 129 } 130 131 - static inline unsigned long level_mask(int level) 132 { 133 - return -1UL << level_to_offset_bits(level); 134 } 135 136 - static inline unsigned long level_size(int level) 137 { 138 - return 1UL << level_to_offset_bits(level); 139 } 140 141 - static inline unsigned long align_to_level(unsigned long pfn, int level) 142 { 143 return (pfn + level_size(level) - 1) & level_mask(level); 144 } 145 146 static inline unsigned long lvl_to_nr_pages(unsigned int lvl) 147 { 148 - return 1 << min_t(int, (lvl - 1) * LEVEL_STRIDE, MAX_AGAW_PFN_WIDTH); 149 } 150 151 /* VT-d pages must always be _smaller_ than MM pages. Otherwise things
··· 123 return (level - 1) * LEVEL_STRIDE; 124 } 125 126 + static inline int pfn_level_offset(u64 pfn, int level) 127 { 128 return (pfn >> level_to_offset_bits(level)) & LEVEL_MASK; 129 } 130 131 + static inline u64 level_mask(int level) 132 { 133 + return -1ULL << level_to_offset_bits(level); 134 } 135 136 + static inline u64 level_size(int level) 137 { 138 + return 1ULL << level_to_offset_bits(level); 139 } 140 141 + static inline u64 align_to_level(u64 pfn, int level) 142 { 143 return (pfn + level_size(level) - 1) & level_mask(level); 144 } 145 146 static inline unsigned long lvl_to_nr_pages(unsigned int lvl) 147 { 148 + return 1UL << min_t(int, (lvl - 1) * LEVEL_STRIDE, MAX_AGAW_PFN_WIDTH); 149 } 150 151 /* VT-d pages must always be _smaller_ than MM pages. Otherwise things