The pfn_t type uses an unsigned long to store a pfn + flags value. On a 64-bit platform the upper 12 bits of an unsigned long are never used for storing the value of a pfn. However, this is not true on highmem platforms, all 32-bits of a pfn value are used to address a 44-bit physical address space. A pfn_t needs to store a 64-bit value.
Reported-by: Stuart Foster smf.linux@ntlworld.com Reported-by: Julian Margetson runaway@candw.ms Cc: dri-devel@lists.freedesktop.org Link: https://bugzilla.kernel.org/show_bug.cgi?id=112211 Fixes: 01c8f1c44b83 ("mm, dax, gpu: convert vm_insert_mixed to pfn_t") Signed-off-by: Dan Williams dan.j.williams@intel.com --- include/linux/pfn.h | 2 +- include/linux/pfn_t.h | 19 +++++++++---------- kernel/memremap.c | 2 +- 3 files changed, 11 insertions(+), 12 deletions(-)
diff --git a/include/linux/pfn.h b/include/linux/pfn.h index 2d8e49711b63..1132953235c0 100644 --- a/include/linux/pfn.h +++ b/include/linux/pfn.h @@ -10,7 +10,7 @@ * backing is indicated by flags in the high bits of the value. */ typedef struct { - unsigned long val; + u64 val; } pfn_t; #endif
diff --git a/include/linux/pfn_t.h b/include/linux/pfn_t.h index 37448ab5fb5c..94994810c7c0 100644 --- a/include/linux/pfn_t.h +++ b/include/linux/pfn_t.h @@ -9,14 +9,13 @@ * PFN_DEV - pfn is not covered by system memmap by default * PFN_MAP - pfn has a dynamic page mapping established by a device driver */ -#define PFN_FLAGS_MASK (((unsigned long) ~PAGE_MASK) \ - << (BITS_PER_LONG - PAGE_SHIFT)) -#define PFN_SG_CHAIN (1UL << (BITS_PER_LONG - 1)) -#define PFN_SG_LAST (1UL << (BITS_PER_LONG - 2)) -#define PFN_DEV (1UL << (BITS_PER_LONG - 3)) -#define PFN_MAP (1UL << (BITS_PER_LONG - 4)) - -static inline pfn_t __pfn_to_pfn_t(unsigned long pfn, unsigned long flags) +#define PFN_FLAGS_MASK (((u64) ~PAGE_MASK) << (BITS_PER_LONG_LONG - PAGE_SHIFT)) +#define PFN_SG_CHAIN (1ULL << (BITS_PER_LONG_LONG - 1)) +#define PFN_SG_LAST (1ULL << (BITS_PER_LONG_LONG - 2)) +#define PFN_DEV (1ULL << (BITS_PER_LONG_LONG - 3)) +#define PFN_MAP (1ULL << (BITS_PER_LONG_LONG - 4)) + +static inline pfn_t __pfn_to_pfn_t(unsigned long pfn, u64 flags) { pfn_t pfn_t = { .val = pfn | (flags & PFN_FLAGS_MASK), };
@@ -29,7 +28,7 @@ static inline pfn_t pfn_to_pfn_t(unsigned long pfn) return __pfn_to_pfn_t(pfn, 0); }
-extern pfn_t phys_to_pfn_t(phys_addr_t addr, unsigned long flags); +extern pfn_t phys_to_pfn_t(phys_addr_t addr, u64 flags);
static inline bool pfn_t_has_page(pfn_t pfn) { @@ -87,7 +86,7 @@ static inline pmd_t pfn_t_pmd(pfn_t pfn, pgprot_t pgprot) #ifdef __HAVE_ARCH_PTE_DEVMAP static inline bool pfn_t_devmap(pfn_t pfn) { - const unsigned long flags = PFN_DEV|PFN_MAP; + const u64 flags = PFN_DEV|PFN_MAP;
return (pfn.val & flags) == flags; } diff --git a/kernel/memremap.c b/kernel/memremap.c index 3427cca5a2a6..b04ea2f5fbfe 100644 --- a/kernel/memremap.c +++ b/kernel/memremap.c @@ -152,7 +152,7 @@ void devm_memunmap(struct device *dev, void *addr) } EXPORT_SYMBOL(devm_memunmap);
-pfn_t phys_to_pfn_t(phys_addr_t addr, unsigned long flags) +pfn_t phys_to_pfn_t(phys_addr_t addr, u64 flags) { return __pfn_to_pfn_t(addr >> PAGE_SHIFT, flags); }