CVS commit: src

["Taylor R Campbell" <riastradh%netbsd.org@localhost>]

Module Name:    src
Committed By:   riastradh
Date:           Sat Jan 18 07:26:06 UTC 2025

Modified Files:
        src/sys/kern: sys_futex.c
        src/tests/lib/libc/sys: t_futex_ops.c

Log Message:
futex(2): Fix FUTEX_CMP_REQUEUE to always compare even if no waiters.

It must always compare the futex value and fail with EAGAIN on
mismatch, even if there are no waiters.

  FUTEX_CMP_REQUEUE (since Linux 2.6.7)
         This operation first checks whether the location uaddr
         still contains the value val3.  If not, the operation
         fails with the error EAGAIN.  Otherwise, the operation [...]

https://man7.org/linux/man-pages/man2/futex.2.html

PR kern/56828: futex calls in Linux emulation sometimes hang


To generate a diff of this commit:
cvs rdiff -u -r1.20 -r1.21 src/sys/kern/sys_futex.c
cvs rdiff -u -r1.8 -r1.9 src/tests/lib/libc/sys/t_futex_ops.c

Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.