From: Mark Rutland <mark.rutland@arm.com> To: linux-arm-kernel@lists.infradead.org Cc: linux-kernel@vger.kernel.org, adech.fo@gmail.com, aryabinin@virtuozzo.com, catalin.marinas@arm.com, christoffer.dall@linaro.org, dvyukov@google.com, linux-kbuild@vger.kernel.org, mark.rutland@arm.com, mark.zyngier@arm.com, mmarek@suse.com, will.deacon@arm.com, yamada.masahiro@socionext.com Subject: [PATCH 2/4] arm64: prevent instrumentation of LL/SC atomics Date: Mon, 16 Oct 2017 14:24:38 +0100 [thread overview] Message-ID: <20171016132440.38098-3-mark.rutland@arm.com> (raw) In-Reply-To: <20171016132440.38098-1-mark.rutland@arm.com> While we build the LL/SC atomics as a C object file, this does not follow the AAPCS. This does not interoperate with other C code, and can only be called from special wrapper assembly. Bulding a kernel with CONFIG_KCOV and CONFIG_ARM64_LSE_ATOMICS results in the cmopiler inserting calls to __sanitizer_cov_trace_pc within the LL/SC atomics. As __sanitizer_cov_trace_pc is built per the AAPCS, these calls corrupt register values, resulting in failures at boot time. Avoid this (and other similar issues) by opting out of all compiler instrumentation. We can opt-in to specific instrumentation in future if we want to. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will.deacon@arm.com> --- arch/arm64/lib/Makefile | 1 + 1 file changed, 1 insertion(+) diff --git a/arch/arm64/lib/Makefile b/arch/arm64/lib/Makefile index a0abc142c92b..af77516f71b2 100644 --- a/arch/arm64/lib/Makefile +++ b/arch/arm64/lib/Makefile @@ -17,5 +17,6 @@ CFLAGS_atomic_ll_sc.o := -fcall-used-x0 -ffixed-x1 -ffixed-x2 \ -fcall-saved-x10 -fcall-saved-x11 -fcall-saved-x12 \ -fcall-saved-x13 -fcall-saved-x14 -fcall-saved-x15 \ -fcall-saved-x18 +CC_INSTRUMENT_atomic_ll_sc.o := n lib-$(CONFIG_ARCH_HAS_UACCESS_FLUSHCACHE) += uaccess_flushcache.o -- 2.11.0
WARNING: multiple messages have this Message-ID (diff)
From: mark.rutland@arm.com (Mark Rutland) To: linux-arm-kernel@lists.infradead.org Subject: [PATCH 2/4] arm64: prevent instrumentation of LL/SC atomics Date: Mon, 16 Oct 2017 14:24:38 +0100 [thread overview] Message-ID: <20171016132440.38098-3-mark.rutland@arm.com> (raw) In-Reply-To: <20171016132440.38098-1-mark.rutland@arm.com> While we build the LL/SC atomics as a C object file, this does not follow the AAPCS. This does not interoperate with other C code, and can only be called from special wrapper assembly. Bulding a kernel with CONFIG_KCOV and CONFIG_ARM64_LSE_ATOMICS results in the cmopiler inserting calls to __sanitizer_cov_trace_pc within the LL/SC atomics. As __sanitizer_cov_trace_pc is built per the AAPCS, these calls corrupt register values, resulting in failures at boot time. Avoid this (and other similar issues) by opting out of all compiler instrumentation. We can opt-in to specific instrumentation in future if we want to. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will.deacon@arm.com> --- arch/arm64/lib/Makefile | 1 + 1 file changed, 1 insertion(+) diff --git a/arch/arm64/lib/Makefile b/arch/arm64/lib/Makefile index a0abc142c92b..af77516f71b2 100644 --- a/arch/arm64/lib/Makefile +++ b/arch/arm64/lib/Makefile @@ -17,5 +17,6 @@ CFLAGS_atomic_ll_sc.o := -fcall-used-x0 -ffixed-x1 -ffixed-x2 \ -fcall-saved-x10 -fcall-saved-x11 -fcall-saved-x12 \ -fcall-saved-x13 -fcall-saved-x14 -fcall-saved-x15 \ -fcall-saved-x18 +CC_INSTRUMENT_atomic_ll_sc.o := n lib-$(CONFIG_ARCH_HAS_UACCESS_FLUSHCACHE) += uaccess_flushcache.o -- 2.11.0
next prev parent reply other threads:[~2017-10-16 13:25 UTC|newest] Thread overview: 32+ messages / expand[flat|nested] mbox.gz Atom feed top 2017-10-16 13:24 [PATCH 0/4] Cleanup instrumentation avoidance Mark Rutland 2017-10-16 13:24 ` Mark Rutland 2017-10-16 13:24 ` [PATCH 1/4] kbuild: allow global override of CC instrumentation Mark Rutland 2017-10-16 13:24 ` Mark Rutland 2017-10-17 10:37 ` Will Deacon 2017-10-17 10:37 ` Will Deacon 2017-10-16 13:24 ` Mark Rutland [this message] 2017-10-16 13:24 ` [PATCH 2/4] arm64: prevent instrumentation of LL/SC atomics Mark Rutland 2017-10-17 10:03 ` Will Deacon 2017-10-17 10:03 ` Will Deacon 2017-10-17 10:54 ` Mark Rutland 2017-10-17 10:54 ` Mark Rutland 2017-10-17 10:58 ` Will Deacon 2017-10-17 10:58 ` Will Deacon 2017-10-17 11:10 ` Mark Rutland 2017-10-17 11:10 ` Mark Rutland 2017-10-17 11:38 ` Will Deacon 2017-10-17 11:38 ` Will Deacon 2017-10-17 12:55 ` Mark Rutland 2017-10-17 12:55 ` Mark Rutland 2017-10-18 14:16 ` Will Deacon 2017-10-18 14:16 ` Will Deacon 2017-10-16 13:24 ` [PATCH 3/4] kvm/arm64: simplify CC instrumentation opt-out Mark Rutland 2017-10-16 13:24 ` Mark Rutland 2017-10-17 14:50 ` Christoffer Dall 2017-10-17 14:50 ` Christoffer Dall 2017-10-16 13:24 ` [PATCH 4/4] arm64: vdso: remove pointless gcov option Mark Rutland 2017-10-16 13:24 ` Mark Rutland 2017-10-17 13:56 ` Mark Rutland 2017-10-17 13:56 ` Mark Rutland 2017-10-16 13:35 ` [PATCH 0/4] Cleanup instrumentation avoidance Mark Rutland 2017-10-16 13:35 ` Mark Rutland
Reply instructions: You may reply publicly to this message via plain-text email using any one of the following methods: * Save the following mbox file, import it into your mail client, and reply-to-all from there: mbox Avoid top-posting and favor interleaved quoting: https://en.wikipedia.org/wiki/Posting_style#Interleaved_style * Reply using the --to, --cc, and --in-reply-to switches of git-send-email(1): git send-email \ --in-reply-to=20171016132440.38098-3-mark.rutland@arm.com \ --to=mark.rutland@arm.com \ --cc=adech.fo@gmail.com \ --cc=aryabinin@virtuozzo.com \ --cc=catalin.marinas@arm.com \ --cc=christoffer.dall@linaro.org \ --cc=dvyukov@google.com \ --cc=linux-arm-kernel@lists.infradead.org \ --cc=linux-kbuild@vger.kernel.org \ --cc=linux-kernel@vger.kernel.org \ --cc=mark.zyngier@arm.com \ --cc=mmarek@suse.com \ --cc=will.deacon@arm.com \ --cc=yamada.masahiro@socionext.com \ /path/to/YOUR_REPLY https://kernel.org/pub/software/scm/git/docs/git-send-email.html * If your mail client supports setting the In-Reply-To header via mailto: links, try the mailto: linkBe sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes, see mirroring instructions on how to clone and mirror all data and code used by this external index.