From: "tip-bot2 for Marco Elver" <tip-bot2@linutronix.de>
To: linux-tip-commits@vger.kernel.org
Cc: Marco Elver <elver@google.com>, Borislav Petkov <bp@suse.de>,
"Peter Zijlstra (Intel)" <peterz@infradead.org>,
Will Deacon <will@kernel.org>, x86 <x86@kernel.org>,
LKML <linux-kernel@vger.kernel.org>
Subject: [tip: locking/kcsan] kcsan: Restrict supported compilers
Date: Fri, 22 May 2020 16:08:48 -0000 [thread overview]
Message-ID: <159016372876.17951.8987293985119856596.tip-bot2@tip-bot2> (raw)
In-Reply-To: <CANpmjNMTsY_8241bS7=XAfqvZHFLrVEkv_uM4aDUWE_kh3Rvbw@mail.gmail.com>
The following commit has been merged into the locking/kcsan branch of tip:
Commit-ID: 0d473b1d6e5c240f8ffed02715c718024802d0fa
Gitweb: https://git.kernel.org/tip/0d473b1d6e5c240f8ffed02715c718024802d0fa
Author: Marco Elver <elver@google.com>
AuthorDate: Thu, 21 May 2020 16:20:42 +02:00
Committer: Borislav Petkov <bp@suse.de>
CommitterDate: Fri, 22 May 2020 14:46:02 +02:00
kcsan: Restrict supported compilers
The first version of Clang that supports -tsan-distinguish-volatile will
be able to support KCSAN. The first Clang release to do so, will be
Clang 11. This is due to satisfying all the following requirements:
1. Never emit calls to __tsan_func_{entry,exit}.
2. __no_kcsan functions should not call anything, not even
kcsan_{enable,disable}_current(), when using __{READ,WRITE}_ONCE => Requires
leaving them plain!
3. Support atomic_{read,set}*() with KCSAN, which rely on
arch_atomic_{read,set}*() using __{READ,WRITE}_ONCE() => Because of
#2, rely on Clang 11's -tsan-distinguish-volatile support. We will
double-instrument atomic_{read,set}*(), but that's reasonable given
it's still lower cost than the data_race() variant due to avoiding 2
extra calls (kcsan_{en,dis}able_current() calls).
4. __always_inline functions inlined into __no_kcsan functions are never
instrumented.
5. __always_inline functions inlined into instrumented functions are
instrumented.
6. __no_kcsan_or_inline functions may be inlined into __no_kcsan functions =>
Implies leaving 'noinline' off of __no_kcsan_or_inline.
7. Because of #6, __no_kcsan and __no_kcsan_or_inline functions should never be
spuriously inlined into instrumented functions, causing the accesses of the
__no_kcsan function to be instrumented.
Older versions of Clang do not satisfy #3. The latest GCC currently
doesn't support at least #1, #3, and #7.
Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Will Deacon <will@kernel.org>
Link: https://lkml.kernel.org/r/CANpmjNMTsY_8241bS7=XAfqvZHFLrVEkv_uM4aDUWE_kh3Rvbw@mail.gmail.com
Link: https://lkml.kernel.org/r/20200521142047.169334-7-elver@google.com
---
lib/Kconfig.kcsan | 9 ++++++++-
1 file changed, 8 insertions(+), 1 deletion(-)
diff --git a/lib/Kconfig.kcsan b/lib/Kconfig.kcsan
index b5d88ac..5ee88e5 100644
--- a/lib/Kconfig.kcsan
+++ b/lib/Kconfig.kcsan
@@ -3,6 +3,12 @@
config HAVE_ARCH_KCSAN
bool
+config HAVE_KCSAN_COMPILER
+ def_bool CC_IS_CLANG && $(cc-option,-fsanitize=thread -mllvm -tsan-distinguish-volatile=1)
+ help
+ For the list of compilers that support KCSAN, please see
+ <file:Documentation/dev-tools/kcsan.rst>.
+
config KCSAN_KCOV_BROKEN
def_bool KCOV && CC_HAS_SANCOV_TRACE_PC
depends on CC_IS_CLANG
@@ -15,7 +21,8 @@ config KCSAN_KCOV_BROKEN
menuconfig KCSAN
bool "KCSAN: dynamic data race detector"
- depends on HAVE_ARCH_KCSAN && DEBUG_KERNEL && !KASAN
+ depends on HAVE_ARCH_KCSAN && HAVE_KCSAN_COMPILER
+ depends on DEBUG_KERNEL && !KASAN
depends on !KCSAN_KCOV_BROKEN
select STACKTRACE
help
next prev parent reply other threads:[~2020-05-22 16:09 UTC|newest]
Thread overview: 127+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-05-11 20:41 [PATCH v5 00/18] Rework READ_ONCE() to improve codegen Will Deacon
2020-05-11 20:41 ` [PATCH v5 01/18] sparc32: mm: Fix argument checking in __srmmu_get_nocache() Will Deacon
2020-05-12 14:37 ` [tip: locking/kcsan] " tip-bot2 for Will Deacon
2020-05-11 20:41 ` [PATCH v5 02/18] sparc32: mm: Restructure sparc32 MMU page-table layout Will Deacon
2020-05-12 14:37 ` [tip: locking/kcsan] " tip-bot2 for Will Deacon
2020-05-11 20:41 ` [PATCH v5 03/18] sparc32: mm: Change pgtable_t type to pte_t * instead of struct page * Will Deacon
2020-05-12 14:36 ` [tip: locking/kcsan] " tip-bot2 for Will Deacon
2020-05-11 20:41 ` [PATCH v5 04/18] sparc32: mm: Reduce allocation size for PMD and PTE tables Will Deacon
2020-05-12 14:36 ` [tip: locking/kcsan] " tip-bot2 for Will Deacon
2020-05-17 0:00 ` [PATCH v5 04/18] " Guenter Roeck
2020-05-17 0:07 ` Guenter Roeck
2020-05-18 8:37 ` Will Deacon
2020-05-18 9:18 ` Mike Rapoport
2020-05-18 9:48 ` Guenter Roeck
2020-05-18 14:23 ` Mike Rapoport
2020-05-18 16:08 ` Guenter Roeck
2020-05-18 18:11 ` Ira Weiny
2020-05-18 18:14 ` Ira Weiny
2020-05-18 18:09 ` Guenter Roeck
2020-05-18 18:21 ` Ira Weiny
2020-05-18 19:15 ` Mike Rapoport
2020-05-19 16:40 ` Guenter Roeck
2020-05-20 17:03 ` Mike Rapoport
2020-05-20 19:03 ` Guenter Roeck
2020-05-20 19:51 ` Mike Rapoport
2020-05-21 23:02 ` Guenter Roeck
2020-05-24 12:32 ` Mike Rapoport
2020-05-24 14:01 ` Guenter Roeck
2020-05-26 13:26 ` Will Deacon
2020-05-26 14:01 ` Will Deacon
2020-05-26 15:21 ` Mike Rapoport
2020-05-26 16:18 ` Guenter Roeck
2020-05-26 16:29 ` Mike Rapoport
2020-05-26 17:15 ` Guenter Roeck
2020-05-11 20:41 ` [PATCH v5 05/18] compiler/gcc: Raise minimum GCC version for kernel builds to 4.8 Will Deacon
2020-05-12 14:36 ` [tip: locking/kcsan] " tip-bot2 for Will Deacon
2020-05-11 20:41 ` [PATCH v5 06/18] netfilter: Avoid assigning 'const' pointer to non-const pointer Will Deacon
2020-05-12 14:36 ` [tip: locking/kcsan] " tip-bot2 for Will Deacon
2020-05-11 20:41 ` [PATCH v5 07/18] net: tls: " Will Deacon
2020-05-12 14:36 ` [tip: locking/kcsan] " tip-bot2 for Will Deacon
2020-05-11 20:41 ` [PATCH v5 08/18] fault_inject: Don't rely on "return value" from WRITE_ONCE() Will Deacon
2020-05-12 14:36 ` [tip: locking/kcsan] " tip-bot2 for Will Deacon
2020-05-11 20:41 ` [PATCH v5 09/18] arm64: csum: Disable KASAN for do_csum() Will Deacon
2020-05-12 14:36 ` [tip: locking/kcsan] " tip-bot2 for Will Deacon
2020-05-11 20:41 ` [PATCH v5 10/18] READ_ONCE: Simplify implementations of {READ,WRITE}_ONCE() Will Deacon
2020-05-12 14:36 ` [tip: locking/kcsan] " tip-bot2 for Will Deacon
2020-05-11 20:41 ` [PATCH v5 11/18] READ_ONCE: Enforce atomicity for {READ,WRITE}_ONCE() memory accesses Will Deacon
2020-05-12 14:36 ` [tip: locking/kcsan] " tip-bot2 for Will Deacon
2020-05-11 20:41 ` [PATCH v5 12/18] READ_ONCE: Drop pointer qualifiers when reading from scalar types Will Deacon
2020-05-12 14:36 ` [tip: locking/kcsan] " tip-bot2 for Will Deacon
2020-05-11 20:41 ` [PATCH v5 13/18] locking/barriers: Use '__unqual_scalar_typeof' for load-acquire macros Will Deacon
2020-05-12 14:36 ` [tip: locking/kcsan] " tip-bot2 for Will Deacon
2020-05-11 20:41 ` [PATCH v5 14/18] arm64: barrier: Use '__unqual_scalar_typeof' for acquire/release macros Will Deacon
2020-05-12 14:36 ` [tip: locking/kcsan] " tip-bot2 for Will Deacon
2020-05-11 20:41 ` [PATCH v5 15/18] gcov: Remove old GCC 3.4 support Will Deacon
2020-05-12 14:36 ` [tip: locking/kcsan] " tip-bot2 for Will Deacon
2020-05-11 20:41 ` [PATCH v5 16/18] kcsan: Rework data_race() so that it can be used by READ_ONCE() Will Deacon
2020-05-12 14:36 ` [tip: locking/kcsan] " tip-bot2 for Will Deacon
2020-05-11 20:41 ` [PATCH v5 17/18] READ_ONCE: Use data_race() to avoid KCSAN instrumentation Will Deacon
2020-05-12 8:23 ` Peter Zijlstra
2020-05-12 9:49 ` Will Deacon
2020-05-12 14:36 ` [tip: locking/kcsan] " tip-bot2 for Will Deacon
2020-05-20 22:17 ` Borislav Petkov
2020-05-20 22:30 ` Marco Elver
2020-05-21 7:25 ` Borislav Petkov
2020-05-21 9:37 ` Marco Elver
2020-05-21 3:30 ` Nathan Chancellor
2020-05-22 16:08 ` [tip: locking/kcsan] compiler.h: Avoid nested statement expression in data_race() tip-bot2 for Marco Elver
2020-05-11 20:41 ` [PATCH v5 18/18] linux/compiler.h: Remove redundant '#else' Will Deacon
2020-05-12 14:36 ` [tip: locking/kcsan] " tip-bot2 for Will Deacon
2020-05-12 8:18 ` [PATCH v5 00/18] Rework READ_ONCE() to improve codegen Peter Zijlstra
2020-05-12 17:53 ` Marco Elver
2020-05-12 18:55 ` Marco Elver
2020-05-12 19:07 ` Peter Zijlstra
2020-05-12 20:31 ` Marco Elver
2020-05-13 11:10 ` Peter Zijlstra
2020-05-13 11:14 ` Peter Zijlstra
2020-05-13 11:48 ` Marco Elver
2020-05-13 12:32 ` Peter Zijlstra
2020-05-13 12:40 ` Will Deacon
2020-05-13 13:15 ` Marco Elver
2020-05-13 13:24 ` Peter Zijlstra
2020-05-13 13:58 ` Marco Elver
2020-05-14 11:21 ` Peter Zijlstra
2020-05-14 11:24 ` Peter Zijlstra
2020-05-14 11:35 ` Peter Zijlstra
2020-05-14 12:01 ` Will Deacon
2020-05-14 12:27 ` Peter Zijlstra
2020-05-14 13:07 ` Marco Elver
2020-05-14 13:14 ` Peter Zijlstra
2020-05-14 12:20 ` Peter Zijlstra
2020-05-14 14:13 ` Peter Zijlstra
2020-05-14 14:20 ` Marco Elver
2020-05-15 9:20 ` Peter Zijlstra
2020-05-13 16:50 ` Will Deacon
2020-05-13 17:32 ` Marco Elver
2020-05-13 17:47 ` Will Deacon
2020-05-13 18:54 ` Marco Elver
2020-05-13 21:25 ` Will Deacon
2020-05-14 7:31 ` Marco Elver
2020-05-14 11:05 ` Will Deacon
2020-05-14 13:35 ` Marco Elver
2020-05-14 13:47 ` Peter Zijlstra
2020-05-14 13:50 ` Peter Zijlstra
2020-05-14 13:56 ` Peter Zijlstra
2020-05-14 14:24 ` Peter Zijlstra
2020-05-14 15:09 ` Thomas Gleixner
2020-05-14 15:29 ` Marco Elver
2020-05-14 19:37 ` Thomas Gleixner
2020-05-15 13:55 ` David Laight
2020-05-15 14:04 ` Marco Elver
2020-05-15 14:07 ` Peter Zijlstra
2020-05-14 15:38 ` Paul E. McKenney
2020-05-22 16:08 ` tip-bot2 for Marco Elver [this message]
2020-06-03 18:52 ` Borislav Petkov
2020-06-03 19:23 ` Marco Elver
2020-06-03 22:05 ` Borislav Petkov
2020-06-08 17:32 ` Martin Liška
2020-06-08 19:56 ` Marco Elver
2020-06-09 11:55 ` Martin Liška
2020-06-09 12:36 ` Martin Liška
2020-06-09 13:45 ` Marco Elver
2020-05-22 16:08 ` [tip: locking/kcsan] kcsan: Remove 'noinline' from __no_kcsan_or_inline tip-bot2 for Marco Elver
2020-05-13 13:21 ` [PATCH v5 00/18] Rework READ_ONCE() to improve codegen David Laight
2020-05-13 16:32 ` Thomas Gleixner
2020-05-12 21:14 ` Will Deacon
2020-05-12 22:00 ` Marco Elver
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