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| author | Steve Capper <steve.capper@linaro.org> | 2013-04-19 15:49:31 +0100 |
|---|---|---|
| committer | Catalin Marinas <catalin.marinas@arm.com> | 2013-04-25 17:45:52 +0100 |
| commit | 4339e3f389081ea90e230a785bdbe10eccd02b71 (patch) | |
| tree | cce5405ebcbdf63dd88da82e94b31afb606293a2 /arch/arm64 | |
| parent | f15a2a12d01573fcf9d2beb657f308845d55fc66 (diff) | |
| download | linux-stable-4339e3f389081ea90e230a785bdbe10eccd02b71.tar.gz linux-stable-4339e3f389081ea90e230a785bdbe10eccd02b71.tar.bz2 linux-stable-4339e3f389081ea90e230a785bdbe10eccd02b71.zip | |
arm64: mm: Correct show_pte behaviour
show_pte makes use of the *_none_or_clear_bad style functions. If a
pgd, pud or pmd is identified as being bad, it will then be cleared.
As show_pte appears to be called from either the user or kernel
fault handlers this side effect can lead to unpredictable behaviour;
especially as TLB entries are not invalidated.
This patch removes the page table sanitisation from show_pte. If a
bad pgd, pud or pmd is encountered it is left unmodified.
Signed-off-by: Steve Capper <steve.capper@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Diffstat (limited to 'arch/arm64')
| -rw-r--r-- | arch/arm64/mm/fault.c | 6 |
1 files changed, 3 insertions, 3 deletions
diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c index afadae6682ed..52638171d6fd 100644 --- a/arch/arm64/mm/fault.c +++ b/arch/arm64/mm/fault.c @@ -57,16 +57,16 @@ void show_pte(struct mm_struct *mm, unsigned long addr) pmd_t *pmd; pte_t *pte; - if (pgd_none_or_clear_bad(pgd)) + if (pgd_none(*pgd) || pgd_bad(*pgd)) break; pud = pud_offset(pgd, addr); - if (pud_none_or_clear_bad(pud)) + if (pud_none(*pud) || pud_bad(*pud)) break; pmd = pmd_offset(pud, addr); printk(", *pmd=%016llx", pmd_val(*pmd)); - if (pmd_none_or_clear_bad(pmd)) + if (pmd_none(*pmd) || pmd_bad(*pmd)) break; pte = pte_offset_map(pmd, addr); |