2021-01-11 15:22:02

by Andreas Schwab

Subject: [PATCH] powerpc/vdso: fix clock_gettime_fallback for vdso32

The second argument of __kernel_clock_gettime64 points to a struct
__kernel_timespec, with 64-bit time_t, so use the clock_gettime64 syscall
in the fallback function for the 32-bit vdso. Similarily,
clock_getres_fallback should use the clock_getres_time64 syscall, though
it isn't yet called from the 32-bit vdso.

Signed-off-by: Andreas Schwab <[email protected]>
---
arch/powerpc/include/asm/vdso/gettimeofday.h | 8 ++++++++
1 file changed, 8 insertions(+)

diff --git a/arch/powerpc/include/asm/vdso/gettimeofday.h b/arch/powerpc/include/asm/vdso/gettimeofday.h
index 81671aa365b3..a26c12df2c9a 100644
--- a/arch/powerpc/include/asm/vdso/gettimeofday.h
+++ b/arch/powerpc/include/asm/vdso/gettimeofday.h
@@ -106,13 +106,21 @@ int gettimeofday_fallback(struct __kernel_old_timeval *_tv, struct timezone *_tz
static __always_inline
int clock_gettime_fallback(clockid_t _clkid, struct __kernel_timespec *_ts)
{
+#ifndef __powerpc64__
+ return do_syscall_2(__NR_clock_gettime64, _clkid, (unsigned long)_ts);
+#else
return do_syscall_2(__NR_clock_gettime, _clkid, (unsigned long)_ts);
+#endif
}

static __always_inline
int clock_getres_fallback(clockid_t _clkid, struct __kernel_timespec *_ts)
{
+#ifndef __powerpc64__
+ return do_syscall_2(__NR_clock_getres_time64, _clkid, (unsigned long)_ts);
+#else
return do_syscall_2(__NR_clock_getres, _clkid, (unsigned long)_ts);
+#endif
}

#ifdef CONFIG_VDSO32
--
2.30.0


--
Andreas Schwab, [email protected]
GPG Key fingerprint = 7578 EB47 D4E5 4D69 2510 2552 DF73 E780 A9DA AEC1
"And now for something completely different."

2021-01-11 16:46:22

by Christophe Leroy

Subject: Re: [PATCH] powerpc/vdso: fix clock_gettime_fallback for vdso32

Le 11/01/2021 à 16:18, Andreas Schwab a écrit :
> The second argument of __kernel_clock_gettime64 points to a struct
> __kernel_timespec, with 64-bit time_t, so use the clock_gettime64 syscall
> in the fallback function for the 32-bit vdso. Similarily,
> clock_getres_fallback should use the clock_getres_time64 syscall, though
> it isn't yet called from the 32-bit vdso.
>
> Signed-off-by: Andreas Schwab <[email protected]>

Fixes: d0e3fc69d00d ("powerpc/vdso: Provide __kernel_clock_gettime64() on vdso32")

> ---
> arch/powerpc/include/asm/vdso/gettimeofday.h | 8 ++++++++
> 1 file changed, 8 insertions(+)
>
> diff --git a/arch/powerpc/include/asm/vdso/gettimeofday.h b/arch/powerpc/include/asm/vdso/gettimeofday.h
> index 81671aa365b3..a26c12df2c9a 100644
> --- a/arch/powerpc/include/asm/vdso/gettimeofday.h
> +++ b/arch/powerpc/include/asm/vdso/gettimeofday.h
> @@ -106,13 +106,21 @@ int gettimeofday_fallback(struct __kernel_old_timeval *_tv, struct timezone *_tz
> static __always_inline
> int clock_gettime_fallback(clockid_t _clkid, struct __kernel_timespec *_ts)
> {
> +#ifndef __powerpc64__

I think we should do like x86, create a second version of clock_gettime_fallback() inside the #ifdef
CONFIG_VDSO32, and move that one in a matching (non existing yet) #else

> + return do_syscall_2(__NR_clock_gettime64, _clkid, (unsigned long)_ts);
> +#else
> return do_syscall_2(__NR_clock_gettime, _clkid, (unsigned long)_ts);
> +#endif
> }
>
> static __always_inline
> int clock_getres_fallback(clockid_t _clkid, struct __kernel_timespec *_ts)
> {
> +#ifndef __powerpc64__

Same.

> + return do_syscall_2(__NR_clock_getres_time64, _clkid, (unsigned long)_ts);
> +#else
> return do_syscall_2(__NR_clock_getres, _clkid, (unsigned long)_ts);
> +#endif
> }
>
> #ifdef CONFIG_VDSO32
>

Christophe