In do_hres(), we currently use whether the return value of __arch_get_ hw_counter() is negative to indicate fallback, but MIPS returns 0 when clock_mode is invalid.
It is sure that MIPS has a bug when clock_mode is invalid and should return ULL_MAX as ARM64 does (Vincenzo has already submitted a patch). But at the time we found another bug: currently update_vsyscall() and update_vsyscall_tz() rely on __arch_use_vsyscall() to update the vdso data, which causes __cvdso_clock_getres() and some other functions get wrong results when clock_mode is invalid. So, in this patch we update vdso data unconditionally.
Fixes: 44f57d788e7deecb50 ("timekeeping: Provide a generic update_vsyscall() implementation") Cc: stable@vger.kernel.org Cc: Arnd Bergmann arnd@arndb.de Cc: Paul Burton paul.burton@mips.com Cc: linux-mips@vger.kernel.org Cc: linux-arm-kernel@lists.infradead.org Signed-off-by: Huacai Chen chenhc@lemote.com --- kernel/time/vsyscall.c | 9 +++------ 1 file changed, 3 insertions(+), 6 deletions(-)
diff --git a/kernel/time/vsyscall.c b/kernel/time/vsyscall.c index 4bc37ac..5ee0f77 100644 --- a/kernel/time/vsyscall.c +++ b/kernel/time/vsyscall.c @@ -110,8 +110,7 @@ void update_vsyscall(struct timekeeper *tk) nsec = nsec + tk->wall_to_monotonic.tv_nsec; vdso_ts->sec += __iter_div_u64_rem(nsec, NSEC_PER_SEC, &vdso_ts->nsec);
- if (__arch_use_vsyscall(vdata)) - update_vdso_data(vdata, tk); + update_vdso_data(vdata, tk);
__arch_update_vsyscall(vdata, tk);
@@ -124,10 +123,8 @@ void update_vsyscall_tz(void) { struct vdso_data *vdata = __arch_get_k_vdso_data();
- if (__arch_use_vsyscall(vdata)) { - vdata[CS_HRES_COARSE].tz_minuteswest = sys_tz.tz_minuteswest; - vdata[CS_HRES_COARSE].tz_dsttime = sys_tz.tz_dsttime; - } + vdata[CS_HRES_COARSE].tz_minuteswest = sys_tz.tz_minuteswest; + vdata[CS_HRES_COARSE].tz_dsttime = sys_tz.tz_dsttime;
__arch_sync_vdso_data(vdata); }