s390/vdso: fix initializing and updating of vdso_data
Li Wang reported that clock_gettime(CLOCK_MONOTONIC_RAW, ...) returns incorrect values when time is provided via vdso instead of system call: vdso_ts_nsec = 4484351380985507, vdso_ts.tv_sec = 4484351, vdso_ts.tv_nsec = 380985507 sys_ts_nsec = 1446923235377, sys_ts.tv_sec = 1446, sys_ts.tv_nsec = 923235377 Within the s390 specific vdso function __arch_get_hw_counter() reads tod clock steering values from the arch_data member of the passed in vdso_data structure. Problem is that only for the CS_HRES_COARSE vdso_data arch_data is initialized and gets updated. The CS_RAW specific vdso_data does not contain any valid tod_clock_steering information, which explains the different values. Fix this by initializing and updating all vdso_datas. Reported-by: Li Wang <liwang@redhat.com> Tested-by: Li Wang <liwang@redhat.com> Fixes: 1ba2d6c0 ("s390/vdso: simplify __arch_get_hw_counter()") Link: https://lore.kernel.org/linux-s390/YFnxr1ZlMIOIqjfq@osiris Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
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