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| author |   Christopher M. Riedl <cmr@informatik.wtf> | 2019-04-15 22:26:38 -0500 |
|---|---|---|
| committer |   Michael Ellerman <mpe@ellerman.id.au> | 2019-05-03 02:54:57 +1000 |
| commit | 0acb5f64560a052fd66ab37b212a72964847160f (patch) | |
| tree | 51ab809e5bc5f343e540f4496d2c7af8a60e9847 /arch/powerpc/Kconfig.debug | |
| parent | powerpc/boot: Fix missing check of lseek() return value (diff) | |
| download | linux-dev-0acb5f64560a052fd66ab37b212a72964847160f.tar.xz linux-dev-0acb5f64560a052fd66ab37b212a72964847160f.zip | |
powerpc/xmon: add read-only mode
Operations which write to memory and special purpose registers should be
restricted on systems with integrity guarantees (such as Secure Boot)
and, optionally, to avoid self-destructive behaviors.
Add a config option, XMON_DEFAULT_RO_MODE, to set default xmon behavior.
The kernel cmdline options xmon=ro and xmon=rw override this default.
The following xmon operations are affected:
memops:
disable memmove
disable memset
disable memzcan
memex:
no-op'd mwrite
super_regs:
no-op'd write_spr
bpt_cmds:
disable
proc_call:
disable
Signed-off-by: Christopher M. Riedl <cmr@informatik.wtf>
Reviewed-by: Oliver O'Halloran <oohall@gmail.com>
Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Diffstat (limited to 'arch/powerpc/Kconfig.debug')
| -rw-r--r-- | arch/powerpc/Kconfig.debug | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/arch/powerpc/Kconfig.debug b/arch/powerpc/Kconfig.debug index e9ae650c8e93..c59920920ddc 100644 --- a/arch/powerpc/Kconfig.debug +++ b/arch/powerpc/Kconfig.debug @@ -117,6 +117,14 @@ config XMON_DISASSEMBLY to say Y here, unless you're building for a memory-constrained system. +config XMON_DEFAULT_RO_MODE + bool "Restrict xmon to read-only operations by default" + depends on XMON + default y + help + Operate xmon in read-only mode. The cmdline options 'xmon=rw' and + 'xmon=ro' override this default. + config DEBUGGER bool depends on KGDB || XMON |