From mboxrd@z Thu Jan 1 00:00:00 1970 From: samitolvanen@google.com (Sami Tolvanen) Date: Fri, 3 Nov 2017 10:12:00 -0700 Subject: [PATCH 13/15] arm64: add a workaround for GNU gold with ARM64_MODULE_PLTS In-Reply-To: <20171103171203.107569-1-samitolvanen@google.com> References: <20171103171203.107569-1-samitolvanen@google.com> Message-ID: <20171103171203.107569-17-samitolvanen@google.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org CONFIG_CLANG_LTO depends on GNU gold and due to a known bug, the linker crashes when ARM64_MODULE_PLTS is enabled: https://sourceware.org/bugzilla/show_bug.cgi?id=14592 To work around the problem, this change: 1) Enables ARM64_MODULE_PLTS only when it's needed, i.e. when RANDOMIZE_MODULE_REGION_FULL is selected, 2) and disables RANDOMIZE_MODULE_REGION_FULL with clang LTO. Signed-off-by: Sami Tolvanen --- arch/arm64/Kconfig | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index 43ccddb7c8ec..a301fdc90319 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -997,8 +997,8 @@ config RELOCATABLE config RANDOMIZE_BASE bool "Randomize the address of the kernel image" - select ARM64_MODULE_PLTS if MODULES select RELOCATABLE + select ARM64_MODULE_PLTS if RANDOMIZE_MODULE_REGION_FULL help Randomizes the virtual address at which the kernel image is loaded, as a security feature that deters exploit attempts @@ -1016,7 +1016,7 @@ config RANDOMIZE_BASE config RANDOMIZE_MODULE_REGION_FULL bool "Randomize the module region independently from the core kernel" - depends on RANDOMIZE_BASE + depends on RANDOMIZE_BASE && !CLANG_LTO default y help Randomizes the location of the module region without considering the -- 2.15.0.403.gc27cc4dac6-goog