Re: selftests: Linux Kernel Dump Test Module output

[Kees Cook]

On Mon, Feb 17, 2020 at 04:39:37PM +0530, Naresh Kamboju wrote:
> The selftest lkdtm test failed on x86_64 and arm64.
> am I missing any pre-requisite?
> [...]
> ref:
> https://qa-reports.linaro.org/lkft/linux-mainline-oe/build/v5.6-rc1-19-g359c92c02bfa/testrun/1212254/log

Looking at this, I see debugfs mounted, I see LKDTM enabled, but I see
the console freak out just as lkdtm starts:

[  349.262263] kselftest: Running tests in lkdtm
#      4	0x0000000000401014 ?? ??0
0x0000000000401014: ??_??0 #
#      5	0x00007f9de1221a56 ?? ??0
0x00007f9de1221a56: ??_??0 #
#      6	0x0000000000401399 ?? ??0
0x0000000000401399: ??_??0 #
#   madvise failed,
failed,: _ #
#   addr 0x7f9de1000000
0x7f9de1000000: _ #
#   length 0x200000
0x200000: _ #
#   src_type 0
0: _ #
# Testing guest mode PA-bitsANY, VA-bits48,  4K pages
guest: mode_PA-bitsANY, #
# Guest physical address width detected 39
physical: address_width #
[FAIL] 11 selftests kvm vmx_dirty_log_test # exit=254

Is a kvm test running at the same time? It just looks like the entire
console goes silent (which would certainly make the lkdtm tests fail)

> https://qa-reports.linaro.org/lkft/linux-mainline-oe/build/v5.5-11440-gd1ea35f4cdd4/testrun/1202720/log

Similar happens here, only this time it seems to be gpio tests?

[  363.276824] kselftest: Running tests in lkdtm
# ./gpio-mockup.sh line 89 ./gpio-mockup-chardev No such file or
# directory
line: 89_./gpio-mockup-chardev #
# GPIO gpio-mockup test with ranges <-1,32,-1,32,-1,32> 
gpio-mockup: test_with #
# -1,32,-1,32,-1,32 
...
[  407.481225] test_bpf: #0 TAX jited:1 63 62 132 PASS

The console seems broken for over 40 seconds?

-- 
Kees Cook