On Wed, Jun 02, 2021 at 04:14:47PM +0200, Varad Gautam wrote: > From: Varad Gautam <varad.gautam@xxxxxxxx> > > Some vmexits on a SEV-ES guest need special handling within the guest > before exiting to the hypervisor. This must happen within the guest's > \#VC exception handler, triggered on every non automatic exit. > > Add a KUnit based test to validate Linux's VC handling. The test: > 1. installs a kretprobe on the #VC handler (sev_es_ghcb_hv_call, to > access GHCB before/after the resulting VMGEXIT). > 2. tiggers an NAE. > 3. checks that the kretprobe was hit with the right exit_code available > in GHCB. > > Since relying on kprobes, the test does not cover NMI contexts. > > Signed-off-by: Varad Gautam <varad.gautam@xxxxxxxx> > --- > arch/x86/Kconfig | 9 ++ > arch/x86/kernel/Makefile | 8 ++ > arch/x86/kernel/sev-es-test-vc.c | 155 +++++++++++++++++++++++++++++++ This looks good to me except for the small comment below, thanks Varad. I ran it in an SEV-ES guest and I am seeing the test results in dmesg. Only thing I am missing is a 'rep movs' test for MMIO, but that can be added later, so Tested-by: Joerg Roedel <jroedel@xxxxxxx> Btw, should we create a separate directory for such tests like /arch/x86/tests/ or something along those lines? > diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig > index 0045e1b441902..85b8ac450ba56 100644 > --- a/arch/x86/Kconfig > +++ b/arch/x86/Kconfig > @@ -1543,6 +1543,15 @@ config AMD_MEM_ENCRYPT_ACTIVE_BY_DEFAULT > If set to N, then the encryption of system memory can be > activated with the mem_encrypt=on command line option. > > +config AMD_SEV_ES_TEST_VC > + bool "Test for AMD SEV-ES VC exception handling." > + depends on AMD_MEM_ENCRYPT > + select FUNCTION_TRACER > + select KPROBES > + select KUNIT > + help > + Enable KUnit-based testing for AMD SEV-ES #VC exception handling. > + I think this should be in arch/x86/Kconfig.debug.
