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+# SPDX-License-Identifier: GPL-2.0
+
+config EARLY_PRINTK_USB
+ bool
+
+config X86_VERBOSE_BOOTUP
+ bool "Enable verbose x86 bootup info messages"
+ default y
+ help
+ Enables the informational output from the decompression stage
+ (e.g. bzImage) of the boot. If you disable this you will still
+ see errors. Disable this if you want silent bootup.
+
+config EARLY_PRINTK
+ bool "Early printk" if EXPERT
+ default y
+ help
+ Write kernel log output directly into the VGA buffer or to a serial
+ port.
+
+ This is useful for kernel debugging when your machine crashes very
+ early before the console code is initialized. For normal operation
+ it is not recommended because it looks ugly and doesn't cooperate
+ with klogd/syslogd or the X server. You should normally say N here,
+ unless you want to debug such a crash.
+
+config EARLY_PRINTK_DBGP
+ bool "Early printk via EHCI debug port"
+ depends on EARLY_PRINTK && PCI
+ select EARLY_PRINTK_USB
+ help
+ Write kernel log output directly into the EHCI debug port.
+
+ This is useful for kernel debugging when your machine crashes very
+ early before the console code is initialized. For normal operation
+ it is not recommended because it looks ugly and doesn't cooperate
+ with klogd/syslogd or the X server. You should normally say N here,
+ unless you want to debug such a crash. You need usb debug device.
+
+config EARLY_PRINTK_USB_XDBC
+ bool "Early printk via the xHCI debug port"
+ depends on EARLY_PRINTK && PCI
+ select EARLY_PRINTK_USB
+ help
+ Write kernel log output directly into the xHCI debug port.
+
+ One use for this feature is kernel debugging, for example when your
+ machine crashes very early before the regular console code is
+ initialized. Other uses include simpler, lockless logging instead of
+ a full-blown printk console driver + klogd.
+
+ For normal production environments this is normally not recommended,
+ because it doesn't feed events into klogd/syslogd and doesn't try to
+ print anything on the screen.
+
+ You should normally say N here, unless you want to debug early
+ crashes or need a very simple printk logging facility.
+
+config EFI_PGT_DUMP
+ bool "Dump the EFI pagetable"
+ depends on EFI
+ select 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
+ issues with the mapping of the EFI runtime regions into that
+ table.
+
+config DEBUG_TLBFLUSH
+ bool "Set upper limit of TLB entries to flush one-by-one"
+ depends on DEBUG_KERNEL
+ help
+ X86-only for now.
+
+ This option allows the user to tune the amount of TLB entries the
+ kernel flushes one-by-one instead of doing a full TLB flush. In
+ certain situations, the former is cheaper. This is controlled by the
+ tlb_flushall_shift knob under /sys/kernel/debug/x86. If you set it
+ to -1, the code flushes the whole TLB unconditionally. Otherwise,
+ for positive values of it, the kernel will use single TLB entry
+ invalidating instructions according to the following formula:
+
+ flush_entries <= active_tlb_entries / 2^tlb_flushall_shift
+
+ If in doubt, say "N".
+
+config IOMMU_DEBUG
+ bool "Enable IOMMU debugging"
+ depends on GART_IOMMU && DEBUG_KERNEL
+ depends on X86_64
+ help
+ Force the IOMMU to on even when you have less than 4GB of
+ memory and add debugging code. On overflow always panic. And
+ allow to enable IOMMU leak tracing. Can be disabled at boot
+ time with iommu=noforce. This will also enable scatter gather
+ list merging. Currently not recommended for production
+ code. When you use it make sure you have a big enough
+ IOMMU/AGP aperture. Most of the options enabled by this can
+ be set more finegrained using the iommu= command line
+ options. See Documentation/arch/x86/x86_64/boot-options.rst for more
+ details.
+
+config IOMMU_LEAK
+ bool "IOMMU leak tracing"
+ depends on IOMMU_DEBUG && DMA_API_DEBUG
+ help
+ Add a simple leak tracer to the IOMMU code. This is useful when you
+ are debugging a buggy device driver that leaks IOMMU mappings.
+
+config HAVE_MMIOTRACE_SUPPORT
+ def_bool y
+
+config X86_DECODER_SELFTEST
+ bool "x86 instruction decoder selftest"
+ depends on DEBUG_KERNEL && INSTRUCTION_DECODER
+ depends on !COMPILE_TEST
+ help
+ Perform x86 instruction decoder selftests at build time.
+ This option is useful for checking the sanity of x86 instruction
+ decoder code.
+ If unsure, say "N".
+
+choice
+ prompt "IO delay type"
+ default IO_DELAY_0X80
+
+config IO_DELAY_0X80
+ bool "port 0x80 based port-IO delay [recommended]"
+ help
+ This is the traditional Linux IO delay used for in/out_p.
+ It is the most tested hence safest selection here.
+
+config IO_DELAY_0XED
+ bool "port 0xed based port-IO delay"
+ help
+ Use port 0xed as the IO delay. This frees up port 0x80 which is
+ often used as a hardware-debug port.
+
+config IO_DELAY_UDELAY
+ bool "udelay based port-IO delay"
+ help
+ Use udelay(2) as the IO delay method. This provides the delay
+ while not having any side-effect on the IO port space.
+
+config IO_DELAY_NONE
+ bool "no port-IO delay"
+ help
+ No port-IO delay. Will break on old boxes that require port-IO
+ delay for certain operations. Should work on most new machines.
+
+endchoice
+
+config DEBUG_BOOT_PARAMS
+ bool "Debug boot parameters"
+ depends on DEBUG_KERNEL
+ depends on DEBUG_FS
+ help
+ This option will cause struct boot_params to be exported via debugfs.
+
+config CPA_DEBUG
+ bool "CPA self-test code"
+ depends on DEBUG_KERNEL
+ 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
+ help
+ Enabling this option turns on a quick NMI selftest to verify
+ that the NMI behaves correctly.
+
+ This might help diagnose strange hangs that rely on NMI to
+ function properly.
+
+ If unsure, say N.
+
+config DEBUG_IMR_SELFTEST
+ bool "Isolated Memory Region self test"
+ depends on INTEL_IMR
+ help
+ This option enables automated sanity testing of the IMR code.
+ Some simple tests are run to verify IMR bounds checking, alignment
+ and overlapping. This option is really only useful if you are
+ debugging an IMR memory map or are modifying the IMR code and want to
+ test your changes.
+
+ If unsure say N here.
+
+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"
+ depends on PCI
+ 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
+
+choice
+ prompt "Choose kernel unwinder"
+ default UNWINDER_ORC if X86_64
+ default UNWINDER_FRAME_POINTER if X86_32
+ help
+ This determines which method will be used for unwinding kernel stack
+ traces for panics, oopses, bugs, warnings, perf, /proc/<pid>/stack,
+ livepatch, lockdep, and more.
+
+config UNWINDER_ORC
+ bool "ORC unwinder"
+ depends on X86_64
+ select OBJTOOL
+ help
+ This option enables the ORC (Oops Rewind Capability) unwinder for
+ unwinding kernel stack traces. It uses a custom data format which is
+ a simplified version of the DWARF Call Frame Information standard.
+
+ This unwinder is more accurate across interrupt entry frames than the
+ frame pointer unwinder. It also enables a 5-10% performance
+ improvement across the entire kernel compared to frame pointers.
+
+ Enabling this option will increase the kernel's runtime memory usage
+ by roughly 2-4MB, depending on your kernel config.
+
+config UNWINDER_FRAME_POINTER
+ bool "Frame pointer unwinder"
+ select FRAME_POINTER
+ help
+ This option enables the frame pointer unwinder for unwinding kernel
+ stack traces.
+
+ The unwinder itself is fast and it uses less RAM than the ORC
+ unwinder, but the kernel text size will grow by ~3% and the kernel's
+ overall performance will degrade by roughly 5-10%.
+
+config UNWINDER_GUESS
+ bool "Guess unwinder"
+ depends on EXPERT
+ depends on !STACKDEPOT
+ help
+ This option enables the "guess" unwinder for unwinding kernel stack
+ traces. It scans the stack and reports every kernel text address it
+ finds. Some of the addresses it reports may be incorrect.
+
+ While this option often produces false positives, it can still be
+ useful in many cases. Unlike the other unwinders, it has no runtime
+ overhead.
+
+endchoice
+
+config FRAME_POINTER
+ depends on !UNWINDER_ORC && !UNWINDER_GUESS
+ bool