On Thu, Mar 04, 2021 at 11:06:01AM -0800, Andy Lutomirski wrote: > In principle, the generic entry code is generic, and the goal is to use it > in many architectures once it settles down more. Move CONFIG_DEBUG_ENTRY > to the generic config so that it can be used in the generic entry code and > not just in arch/x86. > > Disable it on arm64. arm64 uses some but not all of the kentry > code, and trying to debug the resulting state machine will be painful. > arm64 can turn it back on when it starts using the entire generic > path.
Can we make this depend on CONFIG_GENERIC_ENTRY instead of !ARM64? That'd be more in line with "use the generic entry code, get the generic functionality". Note that arm64 doesn't select CONFIG_GENERIC_ENTRY today. I see that s390 selects CONFIG_GENERIC_ENTRY, and either way this will enable DEBUG_ENTRY for them, so it'd ve worth checking whether this is ok for them. Sven, thoughts? Thanks, Mark. > > Signed-off-by: Andy Lutomirski <l...@kernel.org> > --- > arch/x86/Kconfig.debug | 10 ---------- > lib/Kconfig.debug | 11 +++++++++++ > 2 files changed, 11 insertions(+), 10 deletions(-) > > diff --git a/arch/x86/Kconfig.debug b/arch/x86/Kconfig.debug > index 80b57e7f4947..a5a52133730c 100644 > --- a/arch/x86/Kconfig.debug > +++ b/arch/x86/Kconfig.debug > @@ -170,16 +170,6 @@ config CPA_DEBUG > help > Do change_page_attr() self-tests every 30 seconds. > > -config DEBUG_ENTRY > - bool "Debug low-level entry code" > - depends on DEBUG_KERNEL > - help > - This option enables sanity checks in x86's low-level entry code. > - Some of these sanity checks may slow down kernel entries and > - exits or otherwise impact performance. > - > - If unsure, say N. > - > config DEBUG_NMI_SELFTEST > bool "NMI Selftest" > depends on DEBUG_KERNEL && X86_LOCAL_APIC > diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug > index 7937265ef879..76549c8afa8a 100644 > --- a/lib/Kconfig.debug > +++ b/lib/Kconfig.debug > @@ -1411,6 +1411,17 @@ config CSD_LOCK_WAIT_DEBUG > > endmenu # lock debugging > > +config DEBUG_ENTRY > + bool "Debug low-level entry code" > + depends on DEBUG_KERNEL > + depends on !ARM64 > + help > + This option enables sanity checks in the low-level entry code. > + Some of these sanity checks may slow down kernel entries and > + exits or otherwise impact performance. > + > + If unsure, say N. > + > config TRACE_IRQFLAGS > depends on TRACE_IRQFLAGS_SUPPORT > bool > -- > 2.29.2 >
