With /proc/pid/maps now being read under per-vma lock protection we can reuse parts of that code to execute PROCMAP_QUERY ioctl also without taking mmap_lock. The change is designed to reduce mmap_lock contention and prevent PROCMAP_QUERY ioctl calls from blocking address space updates. This patchset was split out of the original patchset [1] that introduced per-vma lock usage for /proc/pid/maps reading. It contains PROCMAP_QUERY tests, code refactoring patch to simplify the main change and the actual transition to per-vma lock. Changes since v3 [2] - change lock_vma_range()/unlock_vma_range() parameters, per Lorenzo Stoakes - minimize priv->lock_ctx dereferences by storing it in a local variable, per Lorenzo Stoakes - rename unlock_vma to unlock_ctx_vma, per Lorenzo Stoakes - factored out reset_lock_ctx(), per Lorenzo Stoakes - reset lock_ctx->mmap_locked inside query_vma_teardown(), per Lorenzo Stoakes - add clarifying comments in query_vma_find_by_addr() and procfs_procmap_ioctl(), per Lorenzo Stoakes - refactored error handling code inside query_vma_find_by_addr(), per Lorenzo Stoakes - add Acked-by as changes were cosmetic, per SeongJae Park [1] https://lore.kernel.org/all/20250704060727.724817-1-surenb@xxxxxxxxxx/ [2] https://lore.kernel.org/all/20250806155905.824388-1-surenb@xxxxxxxxxx/ Suren Baghdasaryan (3): selftests/proc: test PROCMAP_QUERY ioctl while vma is concurrently modified fs/proc/task_mmu: factor out proc_maps_private fields used by PROCMAP_QUERY fs/proc/task_mmu: execute PROCMAP_QUERY ioctl under per-vma locks fs/proc/internal.h | 15 +- fs/proc/task_mmu.c | 184 ++++++++++++------ fs/proc/task_nommu.c | 14 +- tools/testing/selftests/proc/proc-maps-race.c | 65 +++++++ 4 files changed, 210 insertions(+), 68 deletions(-) base-commit: c2144e09b922d422346a44d72b674bf61dbd84c0 -- 2.50.1.703.g449372360f-goog
