From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Sasha Levin To: "linux-kernel@vger.kernel.org" , "stable@vger.kernel.org" CC: Andy Shevchenko , Bhumika Goyal , Darren Hart , Linus Torvalds , Peter Zijlstra , Thomas Gleixner , "julia.lawall@lip6.fr" , "platform-driver-x86@vger.kernel.org" , Ingo Molnar , Sasha Levin Subject: [PATCH AUTOSEL for 4.14 097/110] x86/platform/intel-mid: Revert "Make 'bt_sfi_data' const" Date: Sat, 3 Feb 2018 18:01:29 +0000 Message-ID: <20180203180015.29073-97-alexander.levin@microsoft.com> References: <20180203180015.29073-1-alexander.levin@microsoft.com> In-Reply-To: <20180203180015.29073-1-alexander.levin@microsoft.com> Content-Language: en-US Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: From: Andy Shevchenko [ Upstream commit 9d0513d82f1a8fe17b41f113ac5922fa57dbaf5c ] So one of the constification patches unearthed a type casting fragility of the underlying code: 276c87054751 ("x86/platform/intel-mid: Make 'bt_sfi_data' const") converted the struct to be const while it is also used as a temporary container for important data that is used to fill 'parent' and 'name' fields in struct platform_device_info. The compiler doesn't notice this due to an explicit type cast that loses the const - which fragility will be fixed separately. This type cast turned a seemingly trivial const propagation patch into a hard to debug data corruptor and crasher bug. Signed-off-by: Andy Shevchenko Cc: Bhumika Goyal Cc: Darren Hart Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: julia.lawall@lip6.fr Cc: platform-driver-x86@vger.kernel.org Link: http://lkml.kernel.org/r/20171228122523.21802-1-andriy.shevchenko@lin= ux.intel.com Signed-off-by: Ingo Molnar Signed-off-by: Sasha Levin --- arch/x86/platform/intel-mid/device_libs/platform_bt.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/x86/platform/intel-mid/device_libs/platform_bt.c b/arch/x= 86/platform/intel-mid/device_libs/platform_bt.c index dc036e511f48..5a0483e7bf66 100644 --- a/arch/x86/platform/intel-mid/device_libs/platform_bt.c +++ b/arch/x86/platform/intel-mid/device_libs/platform_bt.c @@ -60,7 +60,7 @@ static int __init tng_bt_sfi_setup(struct bt_sfi_data *dd= ata) return 0; } =20 -static const struct bt_sfi_data tng_bt_sfi_data __initdata =3D { +static struct bt_sfi_data tng_bt_sfi_data __initdata =3D { .setup =3D tng_bt_sfi_setup, }; =20 --=20 2.11.0