The patch titled Subject: mm: check rb_subtree_gap correctness has been added to the -mm tree. Its filename is mm-check-rb_subtree_gap-correctness.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/SubmitChecklist when testing your code *** The -mm tree is included into linux-next and is updated there every 3-4 working days ------------------------------------------------------ From: Michel Lespinasse <walken@xxxxxxxxxx> Subject: mm: check rb_subtree_gap correctness When CONFIG_DEBUG_VM_RB is enabled, check that rb_subtree_gap is correctly set for every vma and that mm->highest_vm_end is also correct. Also add an explicit 'bug' variable to track if browse_rb() detected any invalid condition. Signed-off-by: Michel Lespinasse <walken@xxxxxxxxxx> Reviewed-by: Rik van Riel <riel@xxxxxxxxxx> Cc: Hugh Dickins <hughd@xxxxxxxxxx> Cc: Russell King <linux@xxxxxxxxxxxxxxxx> Cc: Ralf Baechle <ralf@xxxxxxxxxxxxxx> Cc: Paul Mundt <lethal@xxxxxxxxxxxx> Cc: "David S. Miller" <davem@xxxxxxxxxxxxx> Cc: Chris Metcalf <cmetcalf@xxxxxxxxxx> Cc: Ingo Molnar <mingo@xxxxxxx> Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Cc: "H. Peter Anvin" <hpa@xxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/mmap.c | 24 ++++++++++++++++-------- 1 file changed, 16 insertions(+), 8 deletions(-) diff -puN mm/mmap.c~mm-check-rb_subtree_gap-correctness mm/mmap.c --- a/mm/mmap.c~mm-check-rb_subtree_gap-correctness +++ a/mm/mmap.c @@ -365,7 +365,7 @@ static void vma_rb_erase(struct vm_area_ #ifdef CONFIG_DEBUG_VM_RB static int browse_rb(struct rb_root *root) { - int i = 0, j; + int i = 0, j, bug = 0; struct rb_node *nd, *pn = NULL; unsigned long prev = 0, pend = 0; @@ -373,29 +373,33 @@ static int browse_rb(struct rb_root *roo struct vm_area_struct *vma; vma = rb_entry(nd, struct vm_area_struct, vm_rb); if (vma->vm_start < prev) - printk("vm_start %lx prev %lx\n", vma->vm_start, prev), i = -1; + printk("vm_start %lx prev %lx\n", vma->vm_start, prev), bug = 1; if (vma->vm_start < pend) - printk("vm_start %lx pend %lx\n", vma->vm_start, pend); + printk("vm_start %lx pend %lx\n", vma->vm_start, pend), bug = 1; if (vma->vm_start > vma->vm_end) - printk("vm_end %lx < vm_start %lx\n", vma->vm_end, vma->vm_start); + printk("vm_end %lx < vm_start %lx\n", vma->vm_end, vma->vm_start), bug = 1; + if (vma->rb_subtree_gap != vma_compute_subtree_gap(vma)) + printk("free gap %lx, correct %lx\n", + vma->rb_subtree_gap, + vma_compute_subtree_gap(vma)), bug = 1; i++; pn = nd; prev = vma->vm_start; pend = vma->vm_end; } j = 0; - for (nd = pn; nd; nd = rb_prev(nd)) { + for (nd = pn; nd; nd = rb_prev(nd)) j++; - } if (i != j) - printk("backwards %d, forwards %d\n", j, i), i = 0; - return i; + printk("backwards %d, forwards %d\n", j, i), bug = 1; + return bug ? -1 : i; } void validate_mm(struct mm_struct *mm) { int bug = 0; int i = 0; + unsigned long highest_address = 0; struct vm_area_struct *vma = mm->mmap; while (vma) { struct anon_vma_chain *avc; @@ -403,11 +407,15 @@ void validate_mm(struct mm_struct *mm) list_for_each_entry(avc, &vma->anon_vma_chain, same_vma) anon_vma_interval_tree_verify(avc); vma_unlock_anon_vma(vma); + highest_address = vma->vm_end; vma = vma->vm_next; i++; } if (i != mm->map_count) printk("map_count %d vm_next %d\n", mm->map_count, i), bug = 1; + if (highest_address != mm->highest_vm_end) + printk("mm->highest_vm_end %lx, found %lx\n", + mm->highest_vm_end, highest_address), bug = 1; i = browse_rb(&mm->mm_rb); if (i != mm->map_count) printk("map_count %d rb %d\n", mm->map_count, i), bug = 1; _ Patches currently in -mm which might be from walken@xxxxxxxxxx are linux-next.patch mm-add-anon_vma_lock-to-validate_mm.patch mm-augment-vma-rbtree-with-rb_subtree_gap.patch mm-check-rb_subtree_gap-correctness.patch mm-check-rb_subtree_gap-correctness-fix.patch mm-rearrange-vm_area_struct-for-fewer-cache-misses.patch mm-rearrange-vm_area_struct-for-fewer-cache-misses-checkpatch-fixes.patch mm-vm_unmapped_area-lookup-function.patch mm-vm_unmapped_area-lookup-function-checkpatch-fixes.patch mm-use-vm_unmapped_area-on-x86_64-architecture.patch mm-fix-cache-coloring-on-x86_64-architecture.patch mm-use-vm_unmapped_area-in-hugetlbfs.patch mm-use-vm_unmapped_area-in-hugetlbfs-on-i386-architecture.patch mm-use-vm_unmapped_area-on-mips-architecture.patch mm-use-vm_unmapped_area-on-mips-architecture-fix.patch mm-use-vm_unmapped_area-on-arm-architecture.patch mm-use-vm_unmapped_area-on-arm-architecture-fix.patch mm-use-vm_unmapped_area-on-sh-architecture.patch mm-use-vm_unmapped_area-on-sh-architecture-fix.patch mm-use-vm_unmapped_area-on-sparc64-architecture.patch mm-use-vm_unmapped_area-on-sparc64-architecture-fix.patch mm-use-vm_unmapped_area-in-hugetlbfs-on-sparc64-architecture.patch mm-use-vm_unmapped_area-on-sparc32-architecture.patch mm-use-vm_unmapped_area-in-hugetlbfs-on-tile-architecture.patch -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html