mirror of https://github.com/torvalds/linux.git
68b5a65248
After a VMA is created with the VM_SOFTDIRTY flag set, /proc/pid/pagemap should report that the VMA's virtual pages are soft-dirty until VM_SOFTDIRTY is cleared (i.e., by the next write of "4" to /proc/pid/clear_refs). However, pagemap ignores the VM_SOFTDIRTY flag for virtual addresses that fall in PTE holes (i.e., virtual addresses that don't have a PMD, PUD, or PGD allocated yet). To observe this bug, use mmap to create a VMA large enough such that there's a good chance that the VMA will occupy an unused PMD, then test the soft-dirty bit on its pages. In practice, I found that a VMA that covered a PMD's worth of address space was big enough. This patch adds the necessary VMA lookup to the PTE hole callback in /proc/pid/pagemap's page walk and sets soft-dirty according to the VMAs' VM_SOFTDIRTY flag. Signed-off-by: Peter Feiner <pfeiner@google.com> Acked-by: Cyrill Gorcunov <gorcunov@openvz.org> Cc: Pavel Emelyanov <xemul@parallels.com> Cc: Hugh Dickins <hughd@google.com> Acked-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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| .. | ||
| Kconfig | ||
| Makefile | ||
| array.c | ||
| base.c | ||
| cmdline.c | ||
| consoles.c | ||
| cpuinfo.c | ||
| devices.c | ||
| fd.c | ||
| fd.h | ||
| generic.c | ||
| inode.c | ||
| internal.h | ||
| interrupts.c | ||
| kcore.c | ||
| kmsg.c | ||
| loadavg.c | ||
| meminfo.c | ||
| namespaces.c | ||
| nommu.c | ||
| page.c | ||
| proc_net.c | ||
| proc_sysctl.c | ||
| proc_tty.c | ||
| root.c | ||
| self.c | ||
| softirqs.c | ||
| stat.c | ||
| task_mmu.c | ||
| task_nommu.c | ||
| uptime.c | ||
| version.c | ||
| vmcore.c | ||