From: Zong Li <zong.li@xxxxxxxxxx> Subject: x86: mm: use ARCH_HAS_DEBUG_WX instead of arch defined Extract DEBUG_WX to mm/Kconfig.debug for shared use. Change to use ARCH_HAS_DEBUG_WX instead of DEBUG_WX defined by arch port. Link: http://lkml.kernel.org/r/430736828d149df3f5b462d291e845ec690e0141.1587455584.git.zong.li@xxxxxxxxxx Signed-off-by: Zong Li <zong.li@xxxxxxxxxx> Cc: Borislav Petkov <bp@xxxxxxxxx> Cc: Catalin Marinas <catalin.marinas@xxxxxxx> Cc: "H. Peter Anvin" <hpa@xxxxxxxxx> Cc: Ingo Molnar <mingo@xxxxxxxxxx> Cc: Palmer Dabbelt <palmer@xxxxxxxxxxx> Cc: Paul Walmsley <paul.walmsley@xxxxxxxxxx> Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Cc: Will Deacon <will@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- arch/x86/Kconfig | 1 + arch/x86/Kconfig.debug | 27 --------------------------- 2 files changed, 1 insertion(+), 27 deletions(-) --- a/arch/x86/Kconfig~x86-mm-use-arch_has_debug_wx-instead-of-arch-defined +++ a/arch/x86/Kconfig @@ -81,6 +81,7 @@ config X86 select ARCH_HAS_SYNC_CORE_BEFORE_USERMODE select ARCH_HAS_SYSCALL_WRAPPER select ARCH_HAS_UBSAN_SANITIZE_ALL + select ARCH_HAS_DEBUG_WX select ARCH_HAVE_NMI_SAFE_CMPXCHG select ARCH_MIGHT_HAVE_ACPI_PDC if ACPI select ARCH_MIGHT_HAVE_PC_PARPORT --- a/arch/x86/Kconfig.debug~x86-mm-use-arch_has_debug_wx-instead-of-arch-defined +++ a/arch/x86/Kconfig.debug @@ -72,33 +72,6 @@ config EFI_PGT_DUMP issues with the mapping of the EFI runtime regions into that table. -config DEBUG_WX - bool "Warn on W+X mappings at boot" - select 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_TLBFLUSH bool "Set upper limit of TLB entries to flush one-by-one" depends on DEBUG_KERNEL _
