On Mon, Jun 23, 2025 at 4:45 PM Al Viro <viro@xxxxxxxxxxxxxxxxxx> wrote: > > On Mon, Jun 23, 2025 at 09:24:22AM +0200, Amir Goldstein wrote: > > On Sun, Jun 22, 2025 at 11:51 PM Al Viro <viro@xxxxxxxxxxxxxxxxxx> wrote: > > > > > > LTP 6763a3650734 "syscalls/fanotify10: Add test cases for evictable > > > ignore mark" has an interesting effect on boxen where FANOTIFY is not > > > enabled. The thing is, tst_brk() ends up calling ->cleanup(). See the > > > problem? > > > SAFE_FILE_PRINTF(CACHE_PRESSURE_FILE, "%d", old_cache_pressure); > > > is executed, even though > > > SAFE_FILE_SCANF(CACHE_PRESSURE_FILE, "%d", &old_cache_pressure); > > > /* Set high priority for evicting inodes */ > > > SAFE_FILE_PRINTF(CACHE_PRESSURE_FILE, "500"); > > > hadn't been. > > > > > > Result: fanotify10 on such kernel configs ends up zeroing > > > /proc/sys/vm/vfs_cache_pressure. > > > > oops. > > strange enough, I cannot reproduce it as something is preventing > > zeroing vfs_cache_pressure: > > > > fanotify23.c:232: TCONF: fanotify not configured in kernel > > fanotify23.c:249: TWARN: Failed to close FILE > > '/proc/sys/vm/vfs_cache_pressure': EINVAL (22) > > How old is your ltp tree? Mine was from late May (81d460ba6737 "overcommit_memory: > Disable optimization for malloc to prevent false positives") My LTP tree is from end of May tag 20250530 > and I'm definitely > seeing that behaviour with fanotify23 as well. No TWARN, though - I have no idea where this strange TWARN is coming from I did not investigate it, but the bug is there anyway, so I sent a fix. Thanks, Amir.
