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author | Dmitry Torokhov <dmitry.torokhov@gmail.com> | 2017-07-25 02:51:18 +0300 |
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committer | Dmitry Torokhov <dmitry.torokhov@gmail.com> | 2017-07-25 02:51:18 +0300 |
commit | 53a7ff8fb785839b87f950fd85433d9c662fac89 (patch) | |
tree | 119840a23e5226d3f258e2309b4ef1d328535dd2 /mm/vmalloc.c | |
parent | 4323418d62fefe48ee5019f2c744c918be06ec69 (diff) | |
parent | 072a7852338af900c302490474939e089f4bd4c4 (diff) | |
download | linux-53a7ff8fb785839b87f950fd85433d9c662fac89.tar.xz |
Merge branch 'bind_unbind' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core into next
This brings in devm_device_add_group() and friends so that we can create
driver-specific device attributes as managed resources.
Diffstat (limited to 'mm/vmalloc.c')
-rw-r--r-- | mm/vmalloc.c | 15 |
1 files changed, 13 insertions, 2 deletions
diff --git a/mm/vmalloc.c b/mm/vmalloc.c index 34a1c3e46ed7..ecc97f74ab18 100644 --- a/mm/vmalloc.c +++ b/mm/vmalloc.c @@ -287,10 +287,21 @@ struct page *vmalloc_to_page(const void *vmalloc_addr) if (p4d_none(*p4d)) return NULL; pud = pud_offset(p4d, addr); - if (pud_none(*pud)) + + /* + * Don't dereference bad PUD or PMD (below) entries. This will also + * identify huge mappings, which we may encounter on architectures + * that define CONFIG_HAVE_ARCH_HUGE_VMAP=y. Such regions will be + * identified as vmalloc addresses by is_vmalloc_addr(), but are + * not [unambiguously] associated with a struct page, so there is + * no correct value to return for them. + */ + WARN_ON_ONCE(pud_bad(*pud)); + if (pud_none(*pud) || pud_bad(*pud)) return NULL; pmd = pmd_offset(pud, addr); - if (pmd_none(*pmd)) + WARN_ON_ONCE(pmd_bad(*pmd)); + if (pmd_none(*pmd) || pmd_bad(*pmd)) return NULL; ptep = pte_offset_map(pmd, addr); |