From: Sami Tolvanen <samitolvanen@google.com>
To: Masahiro Yamada <masahiroy@kernel.org>,
Steven Rostedt <rostedt@goodmis.org>,
Will Deacon <will@kernel.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>,
Peter Zijlstra <peterz@infradead.org>,
Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
"Paul E. McKenney" <paulmck@kernel.org>,
Kees Cook <keescook@chromium.org>,
Nick Desaulniers <ndesaulniers@google.com>,
clang-built-linux@googlegroups.com,
kernel-hardening@lists.openwall.com, linux-arch@vger.kernel.org,
linux-arm-kernel@lists.infradead.org,
linux-kbuild@vger.kernel.org, linux-kernel@vger.kernel.org,
linux-pci@vger.kernel.org,
Sami Tolvanen <samitolvanen@google.com>
Subject: [PATCH v9 15/16] arm64: disable recordmcount with DYNAMIC_FTRACE_WITH_REGS
Date: Fri, 11 Dec 2020 10:46:32 -0800 [thread overview]
Message-ID: <20201211184633.3213045-16-samitolvanen@google.com> (raw)
In-Reply-To: <20201211184633.3213045-1-samitolvanen@google.com>
DYNAMIC_FTRACE_WITH_REGS uses -fpatchable-function-entry, which makes
running recordmcount unnecessary as there are no mcount calls in object
files, and __mcount_loc doesn't need to be generated.
While there's normally no harm in running recordmcount even when it's
not strictly needed, this won't work with LTO as we have LLVM bitcode
instead of ELF objects.
This change selects FTRACE_MCOUNT_USE_PATCHABLE_FUNCTION_ENTRY, which
disables recordmcount when patchable function entries are used instead.
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
Acked-by: Will Deacon <will@kernel.org>
---
arch/arm64/Kconfig | 2 ++
1 file changed, 2 insertions(+)
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index a6b5b7ef40ae..cf7eaaa0fb2f 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -159,6 +159,8 @@ config ARM64
select HAVE_DYNAMIC_FTRACE
select HAVE_DYNAMIC_FTRACE_WITH_REGS \
if $(cc-option,-fpatchable-function-entry=2)
+ select FTRACE_MCOUNT_USE_PATCHABLE_FUNCTION_ENTRY \
+ if DYNAMIC_FTRACE_WITH_REGS
select HAVE_EFFICIENT_UNALIGNED_ACCESS
select HAVE_FAST_GUP
select HAVE_FTRACE_MCOUNT_RECORD
--
2.29.2.576.ga3fc446d84-goog
next prev parent reply other threads:[~2020-12-11 20:28 UTC|newest]
Thread overview: 39+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-12-11 18:46 [PATCH v9 00/16] Add support for Clang LTO Sami Tolvanen
2020-12-11 18:46 ` [PATCH v9 01/16] tracing: move function tracer options to Kconfig Sami Tolvanen
2021-02-24 20:17 ` [PATCH v9 01/16] tracing: move function tracer options to Kconfig (causing parisc build failures) Guenter Roeck
2021-02-24 20:38 ` Kees Cook
2021-02-24 20:54 ` Sami Tolvanen
2021-02-24 22:29 ` Guenter Roeck
2021-02-24 22:28 ` Guenter Roeck
2021-02-24 22:42 ` Kees Cook
2020-12-11 18:46 ` [PATCH v9 02/16] kbuild: add support for Clang LTO Sami Tolvanen
2020-12-11 18:46 ` [PATCH v9 03/16] kbuild: lto: fix module versioning Sami Tolvanen
2020-12-11 18:46 ` [PATCH v9 04/16] kbuild: lto: limit inlining Sami Tolvanen
2020-12-11 18:46 ` [PATCH v9 05/16] kbuild: lto: merge module sections Sami Tolvanen
2020-12-11 18:46 ` [PATCH v9 06/16] kbuild: lto: add a default list of used symbols Sami Tolvanen
2020-12-11 19:32 ` Kees Cook
2020-12-11 19:40 ` Sami Tolvanen
2020-12-11 19:45 ` Nick Desaulniers
2020-12-11 18:46 ` [PATCH v9 07/16] init: lto: ensure initcall ordering Sami Tolvanen
2020-12-11 18:46 ` [PATCH v9 08/16] init: lto: fix PREL32 relocations Sami Tolvanen
2020-12-11 18:46 ` [PATCH v9 09/16] PCI: Fix PREL32 relocations for LTO Sami Tolvanen
2020-12-11 18:46 ` [PATCH v9 10/16] modpost: lto: strip .lto from module names Sami Tolvanen
2020-12-11 18:46 ` [PATCH v9 11/16] scripts/mod: disable LTO for empty.c Sami Tolvanen
2020-12-11 18:46 ` [PATCH v9 12/16] efi/libstub: disable LTO Sami Tolvanen
2020-12-11 18:46 ` [PATCH v9 13/16] drivers/misc/lkdtm: disable LTO for rodata.o Sami Tolvanen
2020-12-11 18:46 ` [PATCH v9 14/16] arm64: vdso: disable LTO Sami Tolvanen
2020-12-11 18:46 ` Sami Tolvanen [this message]
2020-12-11 18:46 ` [PATCH v9 16/16] arm64: allow LTO to be selected Sami Tolvanen
2020-12-11 19:38 ` [PATCH v9 00/16] Add support for Clang LTO Kees Cook
2021-01-09 0:27 ` Kees Cook
2021-01-09 14:54 ` Sedat Dilek
2021-01-09 15:36 ` Josh Poimboeuf
2021-01-09 15:46 ` Sedat Dilek
2021-01-09 16:07 ` Josh Poimboeuf
2021-01-09 16:21 ` Sedat Dilek
2021-01-09 16:32 ` Josh Poimboeuf
2021-01-09 16:45 ` Sedat Dilek
2021-01-09 17:03 ` Josh Poimboeuf
2021-01-09 17:05 ` Josh Poimboeuf
2021-01-09 17:33 ` Sedat Dilek
2021-01-09 23:44 ` Sedat Dilek
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