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| author | Greg Hackmann <ghackmann@google.com> | 2014-08-28 14:00:10 -0700 |
|---|---|---|
| committer | John Stultz <john.stultz@linaro.org> | 2016-02-16 13:54:03 -0800 |
| commit | c6a9c8e51b188d049496643db2cfbb67df65190c (patch) | |
| tree | 823ad677a82987ab1166aa36811436a6c180a841 /tools/perf/scripts/python/failed-syscalls-by-pid.py | |
| parent | 487e34bfedac629ad8af0471ab72ab553871e810 (diff) | |
arm64: check for upper PAGE_SHIFT bits in pfn_valid()
pfn_valid() returns a false positive when the lower (64 - PAGE_SHIFT)
bits match a valid pfn but some of the upper bits are set. This caused
a kernel panic in kpageflags_read() when a userspace utility parsed
/proc/*/pagemap, neglected to discard the upper flag bits, and tried to
lseek()+read() from the corresponding offset in /proc/kpageflags.
A valid pfn will never have the upper PAGE_SHIFT bits set, so simply
check for this before passing the pfn to memblock_is_memory().
Change-Id: Ief5d8cd4dd93cbecd545a634a8d5885865cb5970
Signed-off-by: Greg Hackmann <ghackmann@google.com>
Diffstat (limited to 'tools/perf/scripts/python/failed-syscalls-by-pid.py')
0 files changed, 0 insertions, 0 deletions