Re: [PATCH] mm: /proc/pid/smaps_rollup: fix maple tree search

From: Liam Howlett
Date: Thu Oct 20 2022 - 11:31:45 EST

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In reply to: Hugh Dickins: "[PATCH] mm: /proc/pid/smaps_rollup: fix maple tree search"
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Thanks Hugh. I guess this 'optimisation' was a little more aggressive
and a little more buggy than needed.

Reviewed-by: Liam R. Howlett <Liam.Howlett@xxxxxxxxxx>

* Hugh Dickins <hughd@xxxxxxxxxx> [221018 23:18]:
> /proc/pid/smaps_rollup showed 0 kB for everything: now find first vma.
>
> Fixes: c4c84f06285e ("fs/proc/task_mmu: stop using linked list and highest_vm_end")
> Signed-off-by: Hugh Dickins <hughd@xxxxxxxxxx>
> ---
>
> fs/proc/task_mmu.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> --- 6.1-rc1/fs/proc/task_mmu.c
> +++ linux/fs/proc/task_mmu.c
> @@ -902,7 +902,7 @@ static int show_smaps_rollup(struct seq_
> goto out_put_mm;
>
> hold_task_mempolicy(priv);
> - vma = mas_find(&mas, 0);
> + vma = mas_find(&mas, ULONG_MAX);
>
> if (unlikely(!vma))
> goto empty_set;