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| author | Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> | 2020-10-15 20:04:33 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2020-10-16 11:11:14 -0700 |
| commit | cfc5bbc4e75da4e341b86822c3c8ab1f4d804de5 (patch) | |
| tree | e30ea03e50e864d189c5991b7541fd67946018e1 /mm | |
| parent | 379c926d6334427b35fe7747f7758c865e20e9a9 (diff) | |
| download | linux-cfc5bbc4e75da4e341b86822c3c8ab1f4d804de5.tar.bz2 | |
mm/debug_vm_pgtable/ppc64: avoid setting top bits in radom value
ppc64 use bit 62 to indicate a pte entry (_PAGE_PTE). Avoid setting that
bit in random value.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lkml.kernel.org/r/20200902114222.181353-4-aneesh.kumar@linux.ibm.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm')
| -rw-r--r-- | mm/debug_vm_pgtable.c | 13 |
1 files changed, 10 insertions, 3 deletions
diff --git a/mm/debug_vm_pgtable.c b/mm/debug_vm_pgtable.c index 086309fb9b6f..00649b47f6e0 100644 --- a/mm/debug_vm_pgtable.c +++ b/mm/debug_vm_pgtable.c @@ -44,10 +44,17 @@ * entry type. But these bits might affect the ability to clear entries with * pxx_clear() because of how dynamic page table folding works on s390. So * while loading up the entries do not change the lower 4 bits. It does not - * have affect any other platform. + * have affect any other platform. Also avoid the 62nd bit on ppc64 that is + * used to mark a pte entry. */ -#define S390_MASK_BITS 4 -#define RANDOM_ORVALUE GENMASK(BITS_PER_LONG - 1, S390_MASK_BITS) +#define S390_SKIP_MASK GENMASK(3, 0) +#if __BITS_PER_LONG == 64 +#define PPC64_SKIP_MASK GENMASK(62, 62) +#else +#define PPC64_SKIP_MASK 0x0 +#endif +#define ARCH_SKIP_MASK (S390_SKIP_MASK | PPC64_SKIP_MASK) +#define RANDOM_ORVALUE (GENMASK(BITS_PER_LONG - 1, 0) & ~ARCH_SKIP_MASK) #define RANDOM_NZVALUE GENMASK(7, 0) static void __init pte_basic_tests(unsigned long pfn, pgprot_t prot) |