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1 menu "Kernel hacking"
2
3 source "lib/Kconfig.debug"
4
5 config ARM64_PTDUMP_CORE
6 def_bool n
7
8 config ARM64_PTDUMP_DEBUGFS
9 bool "Export kernel pagetable layout to userspace via debugfs"
10 depends on DEBUG_KERNEL
11 select ARM64_PTDUMP_CORE
12 select DEBUG_FS
13 help
14 Say Y here if you want to show the kernel pagetable layout in a
15 debugfs file. This information is only useful for kernel developers
16 who are working in architecture specific areas of the kernel.
17 It is probably not a good idea to enable this feature in a production
18 kernel.
19
20 If in doubt, say N.
21
22 config PID_IN_CONTEXTIDR
23 bool "Write the current PID to the CONTEXTIDR register"
24 help
25 Enabling this option causes the kernel to write the current PID to
26 the CONTEXTIDR register, at the expense of some additional
27 instructions during context switch. Say Y here only if you are
28 planning to use hardware trace tools with this kernel.
29
30 config ARM64_RANDOMIZE_TEXT_OFFSET
31 bool "Randomize TEXT_OFFSET at build time"
32 help
33 Say Y here if you want the image load offset (AKA TEXT_OFFSET)
34 of the kernel to be randomized at build-time. When selected,
35 this option will cause TEXT_OFFSET to be randomized upon any
36 build of the kernel, and the offset will be reflected in the
37 text_offset field of the resulting Image. This can be used to
38 fuzz-test bootloaders which respect text_offset.
39
40 This option is intended for bootloader and/or kernel testing
41 only. Bootloaders must make no assumptions regarding the value
42 of TEXT_OFFSET and platforms must not require a specific
43 value.
44
45 config DEBUG_WX
46 bool "Warn on W+X mappings at boot"
47 select ARM64_PTDUMP_CORE
48 ---help---
49 Generate a warning if any W+X mappings are found at boot.
50
51 This is useful for discovering cases where the kernel is leaving
52 W+X mappings after applying NX, as such mappings are a security risk.
53 This check also includes UXN, which should be set on all kernel
54 mappings.
55
56 Look for a message in dmesg output like this:
57
58 arm64/mm: Checked W+X mappings: passed, no W+X pages found.
59
60 or like this, if the check failed:
61
62 arm64/mm: Checked W+X mappings: FAILED, <N> W+X pages found.
63
64 Note that even if the check fails, your kernel is possibly
65 still fine, as W+X mappings are not a security hole in
66 themselves, what they do is that they make the exploitation
67 of other unfixed kernel bugs easier.
68
69 There is no runtime or memory usage effect of this option
70 once the kernel has booted up - it's a one time check.
71
72 If in doubt, say "Y".
73
74 config DEBUG_ALIGN_RODATA
75 depends on STRICT_KERNEL_RWX
76 bool "Align linker sections up to SECTION_SIZE"
77 help
78 If this option is enabled, sections that may potentially be marked as
79 read only or non-executable will be aligned up to the section size of
80 the kernel. This prevents sections from being split into pages and
81 avoids a potential TLB penalty. The downside is an increase in
82 alignment and potentially wasted space. Turn on this option if
83 performance is more important than memory pressure.
84
85 If in doubt, say N.
86
87 config DEBUG_EFI
88 depends on EFI && DEBUG_INFO
89 bool "UEFI debugging"
90 help
91 Enable this option to include EFI specific debugging features into
92 the kernel that are only useful when using a debug build of the
93 UEFI firmware
94
95 config ARM64_RELOC_TEST
96 depends on m
97 tristate "Relocation testing module"
98
99 source "drivers/hwtracing/coresight/Kconfig"
100
101 endmenu