Re: [PATCH] MIPS: vdso: flush the vdso data page to update it on all processes

[Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>]

Hello.

On 2/21/2016 3:57 PM, Hauke Mehrtens wrote:

> Without flushing the vdso data page the vdso call is working on dated
> or unsynced data. This resulted in problems where the clock_gettime
> vdso call returned a time 6 seconds later after a 3 sounds sleep,
> while the syscall reported a time 3 sounds later like expected. This

    s/sounds/seconds/ perhaps?

> happened very often and I got these ping results for example:
>
> root@OpenWrt:/# ping 192.168.1.255
> PING 192.168.1.255 (192.168.1.255): 56 data bytes
> 64 bytes from 192.168.1.3: seq=0 ttl=64 time=0.688 ms
> 64 bytes from 192.168.1.3: seq=1 ttl=64 time=4294172.045 ms
> 64 bytes from 192.168.1.3: seq=2 ttl=64 time=4293968.105 ms
> 64 bytes from 192.168.1.3: seq=3 ttl=64 time=4294055.920 ms
> 64 bytes from 192.168.1.3: seq=4 ttl=64 time=4294671.913 ms
>
> The flush is now done like it is done on the arm architecture code.
>
> This was tested on a Lantiq/Intel VRX288 (MIPS BE 34Kc V5.6 CPU with
> two VPEs)
>
> Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>
> Cc: <stable@vger.kernel.org> # v4.4+
[...]

MBR, Sergei