On Wed, Jul 02 2025 at 11:21, Terry Tritton wrote:
Futex_waitv can not accept old_timespec32 struct, so userspace should
sys_futex_wait()
convert it from 32bit to 64bit before syscall in 32bit compatible mode.
This fix is based off [1]
Link: https://lore.kernel.org/all/20231203235117.29677-1-wegao@suse.com/ [1]
Originally-by: Wei Gao wegao@suse.com Signed-off-by: Terry Tritton terry.tritton@linaro.org
Changes in v3:
- Fix signed-off-by chain but for real this time
Changes in v2:
- Fix signed-off-by chain
.../testing/selftests/futex/include/futex2test.h | 15 +++++++++++++++ 1 file changed, 15 insertions(+)
diff --git a/tools/testing/selftests/futex/include/futex2test.h b/tools/testing/selftests/futex/include/futex2test.h index ea79662405bc..6780e51eb2d6 100644 --- a/tools/testing/selftests/futex/include/futex2test.h +++ b/tools/testing/selftests/futex/include/futex2test.h @@ -55,6 +55,13 @@ struct futex32_numa { futex_t numa; }; +#if !defined(__LP64__) +struct timespec64 {
- int64_t tv_sec;
- int64_t tv_nsec;
+}; +#endif
Why not use __kernel_timespec which is the actual data type that syscall requests?
/**
- futex_waitv - Wait at multiple futexes, wake on any
- @waiters: Array of waiters
@@ -65,7 +72,15 @@ struct futex32_numa { static inline int futex_waitv(volatile struct futex_waitv *waiters, unsigned long nr_waiters, unsigned long flags, struct timespec *timo, clockid_t clockid) { +#if !defined(__LP64__)
- struct timespec64 timo64 = {0};
- timo64.tv_sec = timo->tv_sec;
- timo64.tv_nsec = timo->tv_nsec;
- return syscall(__NR_futex_waitv, waiters, nr_waiters, flags, &timo64, clockid);
+#else return syscall(__NR_futex_waitv, waiters, nr_waiters, flags, timo, clockid); +#endif
You simply can do
struct __kernel_timespec ts = { .tv_sec = timo->tv_sec, .tv_nsec = timo->tv_nsec, };
return syscall(__NR_futex_waitv, waiters, nr_waiters, flags, &ts, clockid);
unconditionally. No?
Thanks,
tglx