Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
Pre-existing issues: - [High] Using ACTION_AGAIN when pte_offset_map_lock() fails can create an infinite loop. -- --- Patch [19]: [PATCH v5 19/36] proc: include N_MEMORY_PRIVATE nodes in numa_maps output --- commit 744e7cd9225bc94011608ebdc2dbdb49cbdf8476 Author: Gregory Price <[email protected]> proc: include N_MEMORY_PRIVATE nodes in numa_maps output numa_maps collects per-node page counts in the page-table walkers and emits them in show_numa_map. All three filtered by N_MEMORY, so pages on N_MEMORY_PRIVATE nodes were never gathered/printed. Accept N_MEMORY_PRIVATE pages in both walkers and emit private nodes in show_numa_map, so private-node mappings are visible in numa_maps. > diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c > index 817e3e0f91943..e116cd5f157b9 100644 > --- a/fs/proc/task_mmu.c > +++ b/fs/proc/task_mmu.c [ ... ] > @@ -3414,7 +3415,8 @@ static struct page *can_gather_numa_stats_pmd(pmd_t pmd, > return NULL; > > nid = page_to_nid(page); > - if (!node_isset(nid, node_states[N_MEMORY])) > + if (!node_isset(nid, node_states[N_MEMORY]) && > + !node_isset(nid, node_states[N_MEMORY_PRIVATE])) > return NULL; > > return page; [Severity: High] This is a pre-existing issue, but can the error handling in gather_pte_stats() lead to an infinite loop? When reading from procfs memory mapping files (like numa_maps), pte_offset_map_lock() can fail non-transiently for a PMD migration entry and return NULL: fs/proc/task_mmu.c:gather_pte_stats() { ... orig_pte = pte = pte_offset_map_lock(walk->mm, pmd, addr, &ptl); if (!pte) { walk->action = ACTION_AGAIN; return 0; } ... } Because this sets walk->action = ACTION_AGAIN, wouldn't the walk_pmd_range() core unconditionally retry the same PMD entry indefinitely without making forward progress? The same pattern also appears to exist in smaps_pte_range(), clear_refs_pte_range(), pagemap_pmd_range(), and pagemap_scan_pmd_entry(). [ ... ] -- Sashiko AI review ยท https://sashiko.dev/#/patchset/[email protected]?part=19
