forked from luck/tmp_suning_uos_patched
b30fe6c7ce
The problem is that we check nr_ptes/nr_pmds in exit_mmap() which happens *before* pgd_free(). And if an arch does pte/pmd allocation in pgd_alloc() and frees them in pgd_free() we see offset in counters by the time of the checks. We tried to workaround this by offsetting expected counter value according to FIRST_USER_ADDRESS for both nr_pte and nr_pmd in exit_mmap(). But it doesn't work in some cases: 1. ARM with LPAE enabled also has non-zero USER_PGTABLES_CEILING, but upper addresses occupied with huge pmd entries, so the trick with offsetting expected counter value will get really ugly: we will have to apply it nr_pmds, but not nr_ptes. 2. Metag has non-zero FIRST_USER_ADDRESS, but doesn't do allocation pte/pmd page tables allocation in pgd_alloc(), just setup a pgd entry which is allocated at boot and shared accross all processes. The proposal is to move the check to check_mm() which happens *after* pgd_free() and do proper accounting during pgd_alloc() and pgd_free() which would bring counters to zero if nothing leaked. Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Reported-by: Tyler Baker <tyler.baker@linaro.org> Tested-by: Tyler Baker <tyler.baker@linaro.org> Tested-by: Nishanth Menon <nm@ti.com> Cc: Russell King <linux@arm.linux.org.uk> Cc: James Hogan <james.hogan@imgtec.com> Cc: Guan Xuetao <gxt@mprc.pku.edu.cn> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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| alpha | ||
| arc | ||
| arm | ||
| arm64 | ||
| avr32 | ||
| blackfin | ||
| c6x | ||
| cris | ||
| frv | ||
| hexagon | ||
| ia64 | ||
| m32r | ||
| m68k | ||
| metag | ||
| microblaze | ||
| mips | ||
| mn10300 | ||
| nios2 | ||
| openrisc | ||
| parisc | ||
| powerpc | ||
| s390 | ||
| score | ||
| sh | ||
| sparc | ||
| tile | ||
| um | ||
| unicore32 | ||
| x86 | ||
| xtensa | ||
| .gitignore | ||
| Kconfig | ||