[PATCH v4 0/4] selftests/mm: virtual_address_range: Reduce memory usage and avoid VM_IO access

["Thomas Weißschuh" <thomas.weissschuh@linutronix.de>]

The selftest started failing since commit e93d2521b27f
("x86/vdso: Split virtual clock pages into dedicated mapping")
was merged. While debugging I stumbled upon some memory usage
optimizations.

With these test now runs on a VM with only 60MiB of memory.

Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
---
Changes in v4:
- Pick up review tags
- Correct Fixes: of patch 1
- Drop git rebase commit message artifacts
- Replace strtok_r() with strspn() and strcspn()
- Avoid uninitialized read on error in __get_smap_entry()
- Link to v3: https://lore.kernel.org/r/20250113-virtual_address_range-tests-v3-0-f4a8e6b7feed@linutronix.de

Changes in v3:
- Pick up review tags
- Fix naming around PR_SET_VMA_ANON_NAME helper functions
- Skip selftest if PR_SET_VMA_ANON_NAME is not supported
- Check for VM_IO instead of [vvar name prefix
- Link to v2: https://lore.kernel.org/r/20250110-virtual_address_range-tests-v2-0-262a2bf3c3d0@linutronix.de

Changes in v2:
- Drop /dev/null usage
- Avoid overcommit restrictions by dropping PROT_WRITE
- Avoid high memory usage due to PTEs
- Link to v1: https://lore.kernel.org/r/20250107-virtual_address_range-tests-v1-0-3834a2fb47fe@linutronix.de

---
Thomas Weißschuh (4):
      selftests/mm: virtual_address_range: mmap() without PROT_WRITE
      selftests/mm: virtual_address_range: Unmap chunks after validation
      selftests/mm: vm_util: Split up /proc/self/smaps parsing
      selftests/mm: virtual_address_range: Avoid reading from VM_IO mappings

 tools/testing/selftests/mm/config                  |  1 +
 tools/testing/selftests/mm/virtual_address_range.c | 41 ++++++++++++--
 tools/testing/selftests/mm/vm_util.c               | 66 +++++++++++++++++-----
 tools/testing/selftests/mm/vm_util.h               |  1 +
 4 files changed, 92 insertions(+), 17 deletions(-)
---
base-commit: 3043cb9a517b707c12a3f5879f4970c97bfeb3fb
change-id: 20250107-virtual_address_range-tests-95843766fa97

Best regards,
-- 
Thomas Weißschuh <thomas.weissschuh@linutronix.de>