This is useful for kernel debugging when your machine crashes very
early before the console code is initialized.
+config X86_PTDUMP_CORE
+ def_bool n
+
config X86_PTDUMP
bool "Export kernel pagetable layout to userspace via debugfs"
depends on DEBUG_KERNEL
select DEBUG_FS
+ select X86_PTDUMP_CORE
---help---
Say Y here if you want to show the kernel pagetable layout in a
debugfs file. This information is only useful for kernel developers
config EFI_PGT_DUMP
bool "Dump the EFI pagetable"
- depends on EFI && X86_PTDUMP
+ depends on EFI
+ select X86_PTDUMP_CORE
---help---
Enable this if you want to dump the EFI page table before
enabling virtual mode. This can be used to debug miscellaneous
feature as well as for the change_page_attr() infrastructure.
If in doubt, say "N"
+config DEBUG_WX
+ bool "Warn on W+X mappings at boot"
+ depends on DEBUG_RODATA
+ select X86_PTDUMP_CORE
+ ---help---
+ Generate a warning if any W+X mappings are found at boot.
+
+ This is useful for discovering cases where the kernel is leaving
+ W+X mappings after applying NX, as such mappings are a security risk.
+
+ Look for a message in dmesg output like this:
+
+ x86/mm: Checked W+X mappings: passed, no W+X pages found.
+
+ or like this, if the check failed:
+
+ x86/mm: Checked W+X mappings: FAILED, <N> W+X pages found.
+
+ Note that even if the check fails, your kernel is possibly
+ still fine, as W+X mappings are not a security hole in
+ themselves, what they do is that they make the exploitation
+ of other unfixed kernel bugs easier.
+
+ There is no runtime or memory usage effect of this option
+ once the kernel has booted up - it's a one time check.
+
+ If in doubt, say "Y".
+
config DEBUG_SET_MODULE_RONX
bool "Set loadable kernel module data as NX and text as RO"
depends on MODULES
If unsure, say N.
+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.
+
+ This is currently used to help test NMI code.
+
+ If unsure, say N.
+
config DEBUG_NMI_SELFTEST
bool "NMI Selftest"
depends on DEBUG_KERNEL && X86_LOCAL_APIC
If unsure, say N.
+config X86_DEBUG_FPU
+ bool "Debug the x86 FPU code"
+ depends on DEBUG_KERNEL
+ default y
+ ---help---
+ If this option is enabled then there will be extra sanity
+ checks and (boot time) debug printouts added to the kernel.
+ This debugging adds some small amount of runtime overhead
+ to the kernel.
+
+ If unsure, say N.
+
+config PUNIT_ATOM_DEBUG
+ tristate "ATOM Punit debug driver"
+ select DEBUG_FS
+ select IOSF_MBI
+ ---help---
+ This is a debug driver, which gets the power states
+ of all Punit North Complex devices. The power states of
+ each device is exposed as part of the debugfs interface.
+ The current power state can be read from
+ /sys/kernel/debug/punit_atom/dev_power_state
+
endmenu