kvm-unit-tests hang on Arm FVP with protected mode

kvm-unit-tests hang on Arm FVP with protected mode

[Naresh Kamboju]

kvm-unit-tests consistently hang on Arm FVP when booted with
kvm-arm.mode=protected across both 4K and 64K page-size kernel builds.

Running the same tests with kvm-arm.mode=vhe completes successfully.

Anders, bisected and identified the first bad commit as:

  066daa8d3bc2694c392e14091978043aed7b1f23
  KVM: arm64: Initialize HCRX_EL2 traps in pKVM

Regression Analysis:
- Reproducibility? yes

Test regression: kvm-unit-tests hang on Arm FVP with kvm-arm.mode=protected

Reported-by: Linux Kernel Functional Testing <lkft@linaro.org>

Environment:
Platform: Arm FVP base-revc
Kernel: arm64 (tested with 4K and 64K page sizes)
Mode: kvm-arm.mode=protected (hangs) vs kvm-arm.mode=vhe (passes)
Test suite: kvm-unit-tests (./run_tests.sh -a -t -v)
Cmdline args : kvm-arm.mode=protected
Kernel: Mainline master and Linux next master

Test run log:
INFO: running kvm unit tests ...
+ [ True = false ]
+ ./run_tests.sh -a -t -v
+ tee -a /lava-1/0/tests/0_kvm-unit-tests/automated/linux/kvm-unit-tests/output/result_log.txt
TAP version 13

Links:
https://regressions.linaro.org/lkft/linux-mainline-master/v6.17-rc4/lava/kvm-unit-tests/history/?page=1
https://qa-reports.linaro.org/api/testruns/29720932/log_file/

--
Linaro LKFT
https://lkft.linaro.org

Re: kvm-unit-tests hang on Arm FVP with protected mode

[Marc Zyngier]

On Fri, 05 Sep 2025 13:28:45 +0100,
Naresh Kamboju <naresh.kamboju@linaro.org> wrote:
> 
> kvm-unit-tests consistently hang on Arm FVP when booted with
> kvm-arm.mode=protected across both 4K and 64K page-size kernel builds.
> 
> Running the same tests with kvm-arm.mode=vhe completes successfully.

Do you realise that "kvm-arm.mode=vhe" is not a valid option?

> 
> Anders, bisected and identified the first bad commit as:
> 
>   066daa8d3bc2694c392e14091978043aed7b1f23
>   KVM: arm64: Initialize HCRX_EL2 traps in pKVM
> 
> Regression Analysis:
> - Reproducibility? yes
> 
> Test regression: kvm-unit-tests hang on Arm FVP with kvm-arm.mode=protected
> 
> Reported-by: Linux Kernel Functional Testing <lkft@linaro.org>
> 
> Environment:
> Platform: Arm FVP base-revc
> Kernel: arm64 (tested with 4K and 64K page sizes)
> Mode: kvm-arm.mode=protected (hangs) vs kvm-arm.mode=vhe (passes)
> Test suite: kvm-unit-tests (./run_tests.sh -a -t -v)
> Cmdline args : kvm-arm.mode=protected
> Kernel: Mainline master and Linux next master
> 
> Test run log:
> INFO: running kvm unit tests ...
> + [ True = false ]
> + ./run_tests.sh -a -t -v
> + tee -a /lava-1/0/tests/0_kvm-unit-tests/automated/linux/kvm-unit-tests/output/result_log.txt
> TAP version 13

What do you expect us to do with such a non-report? Can you please, at
the very least, identify which test in that test suite triggers the
failure?

> Links:
> https://regressions.linaro.org/lkft/linux-mainline-master/v6.17-rc4/lava/kvm-unit-tests/history/?page=1

What is there? This link requires a login, and goes to 11 on the
scale of being useless.

	M.

-- 
Jazz isn't dead. It just smells funny.

Re: kvm-unit-tests hang on Arm FVP with protected mode

[Mark Brown]

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On Fri, Sep 05, 2025 at 01:42:07PM +0100, Marc Zyngier wrote:
> Naresh Kamboju <naresh.kamboju@linaro.org> wrote:

> > INFO: running kvm unit tests ...
> > + [ True = false ]
> > + ./run_tests.sh -a -t -v
> > + tee -a /lava-1/0/tests/0_kvm-unit-tests/automated/linux/kvm-unit-tests/output/result_log.txt
> > TAP version 13

> What do you expect us to do with such a non-report? Can you please, at
> the very least, identify which test in that test suite triggers the
> failure?

Looking at the log file that isn't password protected that's the last
line of output so it'll have hung trying to do the first test, based on
the log from another machine:

   https://qa-reports.linaro.org/lkft/linux-next-master/build/next-20250905/testrun/29777055/suite/kvm-unit-tests/test/debug-bp-migration-timeout-duration90s/log

it seems that should be

   ok 1 - selftest-setup: selftest: setup: smp: number of CPUs matches expectation

that's died for the version they're using.

> > Links:
> > https://regressions.linaro.org/lkft/linux-mainline-master/v6.17-rc4/lava/kvm-unit-tests/history/?page=1

> What is there? This link requires a login, and goes to 11 on the
> scale of being useless.

My Linaro account appears to have been disabled at some point so I
can't access it either.  If this is affecting mainline presumably it's
been an issue in at least -next for a while.

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