Re: [PATCH 4.9 00/86] 4.9.88-stable review

From: Naresh Kamboju
Date: Wed Mar 21 2018 - 13:50:13 EST


On 21 March 2018 at 19:02, Greg Kroah-Hartman
<gregkh@xxxxxxxxxxxxxxxxxxx> wrote:
> On Tue, Mar 20, 2018 at 11:49:19PM +0000, Ben Hutchings wrote:
>> On Sun, 2018-03-18 at 11:27 +0100, Greg Kroah-Hartman wrote:
>> > On Sat, Mar 17, 2018 at 03:48:24PM +0530, Naresh Kamboju wrote:
>> [...]
>> > > Results from Linaroâs test farm.
>> > > No regressions on arm64, arm, qemu_x86_64 and x86_64.
>> > >
>> > > NOTE:
>> > > CONFIG_LEGACY_VSYSCALL_EMULATE=y is enabled from config as default.
>> > > Enabled vsyscall=native and vsyscall=none from kernel command line for testing
>> > > selftests/x86/test_vsyscall test case on x86_64 and qemu_x86_64.
>> > >
>> > > test_vdso_64 failed on x86_64 device when vsyscall=none is enabled.
>> > > We will investigate this new test failure.
>> >
>> > I think vsyscall=none just went away :)
>>
>> No, vsyscall=native went away upstream. vsyscall=none should still
>> work everywhere.
>
> Ah, sorry, got that wrong, thanks for the correction.
>
>> However, test_vdso_64 isn't able to detect what the current
>> configuration is and it will crash with vsyscall=none (or the
>> equivalent default in kconfig).


Shall i skip running "test_vdso_64" when vsyscall=none ?
or
Shall we fix the test case to work when vsyscall=none ?

"test_vdso_64" test failed log when vsyscall=none on x86_64.
This is a combination of VSYSCALL_EMULATE=y and kernel cmdline vsyscall=none
With this combination test PASS on qemu_x86_64 fails on real hardware.

[ 744.132422] test_vdso_64[3957] vsyscall attempted with vsyscall=none
ip:ffffffffff600800 cs:33 sp:7ffcf7192e18 ax:ffffffffff600800 si:7ffcf7192e4c
di:7ffcf7192e40
[ 744.146945] test_vdso_64[3957]: segfault at ffffffffff600800
ip ffffffffff600800 sp 00007ffcf7192e18 error 15
[ 744.157058] audit: type=1701 audit(1521968691.345:4): auid=4294967295
uid=0 gid=0 ses=4294967295 subj=kernel pid=3957 comm=\"test_vdso_64\"
exe=\"/opt/kselftests/mainline/x86/test_vdso_64\" sig=11 res=1
./run_kselftest.sh: line 233: 3957 Segmentation fault
(core dumped) ./test_vdso_64 > /tmp/test_vdso_64 2>&1
selftests: test_vdso_64 [FAIL]

>
> That's good to know. Naresh, does that help out?

Yes it helps. Thanks

>
> thanks,
>
> greg k-h