From mboxrd@z Thu Jan 1 00:00:00 1970 From: Peter Zijlstra Subject: Re: [PATCH 4/8] kcsan: Add missing CONFIG_KCSAN_IGNORE_ATOMICS checks Date: Tue, 21 Jul 2020 16:09:29 +0200 Message-ID: <20200721140929.GB10769@hirez.programming.kicks-ass.net> References: <20200721103016.3287832-1-elver@google.com> <20200721103016.3287832-5-elver@google.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51182 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726120AbgGUOJi (ORCPT ); Tue, 21 Jul 2020 10:09:38 -0400 Content-Disposition: inline In-Reply-To: <20200721103016.3287832-5-elver@google.com> Sender: linux-arch-owner@vger.kernel.org List-ID: To: Marco Elver Cc: paulmck@kernel.org, will@kernel.org, arnd@arndb.de, mark.rutland@arm.com, dvyukov@google.com, glider@google.com, kasan-dev@googlegroups.com, linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org On Tue, Jul 21, 2020 at 12:30:12PM +0200, Marco Elver wrote: > Add missing CONFIG_KCSAN_IGNORE_ATOMICS checks for the builtin atomics > instrumentation. > > Signed-off-by: Marco Elver > --- > Added to this series, as it would otherwise cause patch conflicts. > --- > kernel/kcsan/core.c | 25 +++++++++++++++++-------- > 1 file changed, 17 insertions(+), 8 deletions(-) > > diff --git a/kernel/kcsan/core.c b/kernel/kcsan/core.c > index 4633baebf84e..f53524ea0292 100644 > --- a/kernel/kcsan/core.c > +++ b/kernel/kcsan/core.c > @@ -892,14 +892,17 @@ EXPORT_SYMBOL(__tsan_init); > u##bits __tsan_atomic##bits##_load(const u##bits *ptr, int memorder); \ > u##bits __tsan_atomic##bits##_load(const u##bits *ptr, int memorder) \ > { \ > - check_access(ptr, bits / BITS_PER_BYTE, KCSAN_ACCESS_ATOMIC); \ > + if (!IS_ENABLED(CONFIG_KCSAN_IGNORE_ATOMICS)) \ > + check_access(ptr, bits / BITS_PER_BYTE, KCSAN_ACCESS_ATOMIC); \ > return __atomic_load_n(ptr, memorder); \ > } \ > EXPORT_SYMBOL(__tsan_atomic##bits##_load); \ > void __tsan_atomic##bits##_store(u##bits *ptr, u##bits v, int memorder); \ > void __tsan_atomic##bits##_store(u##bits *ptr, u##bits v, int memorder) \ > { \ > - check_access(ptr, bits / BITS_PER_BYTE, KCSAN_ACCESS_WRITE | KCSAN_ACCESS_ATOMIC); \ > + if (!IS_ENABLED(CONFIG_KCSAN_IGNORE_ATOMICS)) \ > + check_access(ptr, bits / BITS_PER_BYTE, \ > + KCSAN_ACCESS_WRITE | KCSAN_ACCESS_ATOMIC); \ > __atomic_store_n(ptr, v, memorder); \ > } \ > EXPORT_SYMBOL(__tsan_atomic##bits##_store) > @@ -908,8 +911,10 @@ EXPORT_SYMBOL(__tsan_init); > u##bits __tsan_atomic##bits##_##op(u##bits *ptr, u##bits v, int memorder); \ > u##bits __tsan_atomic##bits##_##op(u##bits *ptr, u##bits v, int memorder) \ > { \ > - check_access(ptr, bits / BITS_PER_BYTE, \ > - KCSAN_ACCESS_COMPOUND | KCSAN_ACCESS_WRITE | KCSAN_ACCESS_ATOMIC); \ > + if (!IS_ENABLED(CONFIG_KCSAN_IGNORE_ATOMICS)) \ > + check_access(ptr, bits / BITS_PER_BYTE, \ > + KCSAN_ACCESS_COMPOUND | KCSAN_ACCESS_WRITE | \ > + KCSAN_ACCESS_ATOMIC); \ > return __atomic_##op##suffix(ptr, v, memorder); \ > } \ > EXPORT_SYMBOL(__tsan_atomic##bits##_##op) > @@ -937,8 +942,10 @@ EXPORT_SYMBOL(__tsan_init); > int __tsan_atomic##bits##_compare_exchange_##strength(u##bits *ptr, u##bits *exp, \ > u##bits val, int mo, int fail_mo) \ > { \ > - check_access(ptr, bits / BITS_PER_BYTE, \ > - KCSAN_ACCESS_COMPOUND | KCSAN_ACCESS_WRITE | KCSAN_ACCESS_ATOMIC); \ > + if (!IS_ENABLED(CONFIG_KCSAN_IGNORE_ATOMICS)) \ > + check_access(ptr, bits / BITS_PER_BYTE, \ > + KCSAN_ACCESS_COMPOUND | KCSAN_ACCESS_WRITE | \ > + KCSAN_ACCESS_ATOMIC); \ > return __atomic_compare_exchange_n(ptr, exp, val, weak, mo, fail_mo); \ > } \ > EXPORT_SYMBOL(__tsan_atomic##bits##_compare_exchange_##strength) > @@ -949,8 +956,10 @@ EXPORT_SYMBOL(__tsan_init); > u##bits __tsan_atomic##bits##_compare_exchange_val(u##bits *ptr, u##bits exp, u##bits val, \ > int mo, int fail_mo) \ > { \ > - check_access(ptr, bits / BITS_PER_BYTE, \ > - KCSAN_ACCESS_COMPOUND | KCSAN_ACCESS_WRITE | KCSAN_ACCESS_ATOMIC); \ > + if (!IS_ENABLED(CONFIG_KCSAN_IGNORE_ATOMICS)) \ > + check_access(ptr, bits / BITS_PER_BYTE, \ > + KCSAN_ACCESS_COMPOUND | KCSAN_ACCESS_WRITE | \ > + KCSAN_ACCESS_ATOMIC); \ > __atomic_compare_exchange_n(ptr, &exp, val, 0, mo, fail_mo); \ > return exp; \ > } \ *groan*, that could really do with a bucket of '{', '}'. Also, it is inconsistent in style with the existing use in DEFINE_TSAN_VOLATILE_READ_WRITE() where the define causes an early return.