Hi Stefano, > On 23 Jan 2021, at 02:19, Stefano Stabellini <sstabell...@kernel.org> wrote: > > A recent thread [1] has exposed a couple of issues with our current way > of handling EXPERT. > > 1) It is not obvious that "Configure standard Xen features (expert > users)" is actually the famous EXPERT we keep talking about on xen-devel > > 2) It is not obvious when we need to enable EXPERT to get a specific > feature > > In particular if you want to enable ACPI support so that you can boot > Xen on an ACPI platform, you have to enable EXPERT first. But searching > through the kconfig menu it is really not clear (type '/' and "ACPI"): > nothing in the description tells you that you need to enable EXPERT to > get the option. > > So this patch makes things easier by doing two things: > > - introduce a new kconfig option UNSUPPORTED which is clearly to enable > UNSUPPORTED features as defined by SUPPORT.md
That’s a great change which will improve user experience. > > - change EXPERT options to UNSUPPORTED where it makes sense: keep > depending on EXPERT for features made for experts > > - tag unsupported features by adding (UNSUPPORTED) to the one-line > description > Shouldn’t we add (EXPERT) for expert options in the same way for coherency ? Cheers Bertrand > - clarify the EXPERT one-line description > > [1] https://marc.info/?l=xen-devel&m=160333101228981 > > Signed-off-by: Stefano Stabellini <stefano.stabell...@xilinx.com> > CC: andrew.coop...@citrix.com > CC: george.dun...@citrix.com > CC: i...@xenproject.org > CC: jbeul...@suse.com > CC: jul...@xen.org > CC: w...@xen.org > CC: bertrand.marq...@arm.com > > Signed-off-by: Stefano Stabellini <stefano.stabell...@xilinx.com> > --- > Changes in v3: > - improve UNSUPPORTED text description > - avoid changing XEN_SHSTK and EFI_SET_VIRTUAL_ADDRESS_MAP > - update HVM_FEP to be UNSUPPORTED > > Changes in v2: > - introduce UNSUPPORTED > - don't switch all EXPERT options to UNSUPPORTED > > See as reference the v2 thread here: > https://marc.info/?l=xen-devel&m=160566066013723 > --- > xen/Kconfig | 9 ++++++++- > xen/arch/arm/Kconfig | 10 +++++----- > xen/arch/x86/Kconfig | 6 +++--- > xen/common/Kconfig | 2 +- > xen/common/sched/Kconfig | 6 +++--- > 5 files changed, 20 insertions(+), 13 deletions(-) > > diff --git a/xen/Kconfig b/xen/Kconfig > index 34c318bfa2..4a3d988353 100644 > --- a/xen/Kconfig > +++ b/xen/Kconfig > @@ -34,8 +34,15 @@ config DEFCONFIG_LIST > option defconfig_list > default ARCH_DEFCONFIG > > +config UNSUPPORTED > + bool "Configure UNSUPPORTED features" > + help > + This option allows certain unsupported Xen options to be changed, > + which includes non-security-supported, experimental, and tech > + preview features as defined by SUPPORT.md. > + > config EXPERT > - bool "Configure standard Xen features (expert users)" > + bool "Configure EXPERT features" > help > This option allows certain base Xen options and settings > to be disabled or tweaked. This is for specialized environments > diff --git a/xen/arch/arm/Kconfig b/xen/arch/arm/Kconfig > index c3eb13ea73..cca76040e5 100644 > --- a/xen/arch/arm/Kconfig > +++ b/xen/arch/arm/Kconfig > @@ -32,7 +32,7 @@ menu "Architecture Features" > source "arch/Kconfig" > > config ACPI > - bool "ACPI (Advanced Configuration and Power Interface) Support" if > EXPERT > + bool "ACPI (Advanced Configuration and Power Interface) Support > (UNSUPPORTED)" if UNSUPPORTED > depends on ARM_64 > ---help--- > > @@ -49,7 +49,7 @@ config GICV3 > If unsure, say Y > > config HAS_ITS > - bool "GICv3 ITS MSI controller support" if EXPERT > + bool "GICv3 ITS MSI controller support (UNSUPPORTED)" if UNSUPPORTED > depends on GICV3 && !NEW_VGIC > > config HVM > @@ -77,7 +77,7 @@ config SBSA_VUART_CONSOLE > SBSA Generic UART implements a subset of ARM PL011 UART. > > config ARM_SSBD > - bool "Speculative Store Bypass Disable" if EXPERT > + bool "Speculative Store Bypass Disable (UNSUPPORTED)" if UNSUPPORTED > depends on HAS_ALTERNATIVE > default y > help > @@ -87,7 +87,7 @@ config ARM_SSBD > If unsure, say Y. > > config HARDEN_BRANCH_PREDICTOR > - bool "Harden the branch predictor against aliasing attacks" if EXPERT > + bool "Harden the branch predictor against aliasing attacks > (UNSUPPORTED)" if UNSUPPORTED > default y > help > Speculation attacks against some high-performance processors rely on > @@ -104,7 +104,7 @@ config HARDEN_BRANCH_PREDICTOR > If unsure, say Y. > > config TEE > - bool "Enable TEE mediators support" if EXPERT > + bool "Enable TEE mediators support (UNSUPPORTED)" if UNSUPPORTED > default n > help > This option enables generic TEE mediators support. It allows guests > diff --git a/xen/arch/x86/Kconfig b/xen/arch/x86/Kconfig > index 78f351f94b..302334d3e4 100644 > --- a/xen/arch/x86/Kconfig > +++ b/xen/arch/x86/Kconfig > @@ -147,7 +147,7 @@ config BIGMEM > If unsure, say N. > > config HVM_FEP > - bool "HVM Forced Emulation Prefix support" if EXPERT > + bool "HVM Forced Emulation Prefix support (UNSUPPORTED)" if UNSUPPORTED > default DEBUG > depends on HVM > ---help--- > @@ -166,7 +166,7 @@ config HVM_FEP > If unsure, say N. > > config TBOOT > - bool "Xen tboot support" if EXPERT > + bool "Xen tboot support (UNSUPPORTED)" if UNSUPPORTED > default y if !PV_SHIM_EXCLUSIVE > select CRYPTO > ---help--- > @@ -252,7 +252,7 @@ config HYPERV_GUEST > endif > > config MEM_SHARING > - bool "Xen memory sharing support" if EXPERT > + bool "Xen memory sharing support (UNSUPPORTED)" if UNSUPPORTED > depends on HVM > > endmenu > diff --git a/xen/common/Kconfig b/xen/common/Kconfig > index b5c91a1664..39451e8350 100644 > --- a/xen/common/Kconfig > +++ b/xen/common/Kconfig > @@ -272,7 +272,7 @@ config LATE_HWDOM > If unsure, say N. > > config ARGO > - bool "Argo: hypervisor-mediated interdomain communication" if EXPERT > + bool "Argo: hypervisor-mediated interdomain communication > (UNSUPPORTED)" if UNSUPPORTED > ---help--- > Enables a hypercall for domains to ask the hypervisor to perform > data transfer of messages between domains. > diff --git a/xen/common/sched/Kconfig b/xen/common/sched/Kconfig > index 61231aacaa..94c9e20139 100644 > --- a/xen/common/sched/Kconfig > +++ b/xen/common/sched/Kconfig > @@ -15,7 +15,7 @@ config SCHED_CREDIT2 > optimized for lower latency and higher VM density. > > config SCHED_RTDS > - bool "RTDS scheduler support (EXPERIMENTAL)" > + bool "RTDS scheduler support (UNSUPPORTED)" if UNSUPPORTED > default y > ---help--- > The RTDS scheduler is a soft and firm real-time scheduler for > @@ -23,14 +23,14 @@ config SCHED_RTDS > in the cloud, and general low-latency workloads. > > config SCHED_ARINC653 > - bool "ARINC653 scheduler support (EXPERIMENTAL)" > + bool "ARINC653 scheduler support (UNSUPPORTED)" if UNSUPPORTED > default DEBUG > ---help--- > The ARINC653 scheduler is a hard real-time scheduler for single > cores, targeted for avionics, drones, and medical devices. > > config SCHED_NULL > - bool "Null scheduler support (EXPERIMENTAL)" > + bool "Null scheduler support (UNSUPPORTED)" if UNSUPPORTED > default y > ---help--- > The null scheduler is a static, zero overhead scheduler, > -- > 2.17.1 >
