Commit-ID:  9d0513d82f1a8fe17b41f113ac5922fa57dbaf5c
Gitweb:     https://git.kernel.org/tip/9d0513d82f1a8fe17b41f113ac5922fa57dbaf5c
Author:     Andy Shevchenko <andriy.shevche...@linux.intel.com>
AuthorDate: Thu, 28 Dec 2017 14:25:23 +0200
Committer:  Ingo Molnar <mi...@kernel.org>
CommitDate: Mon, 8 Jan 2018 20:01:44 +0100

x86/platform/intel-mid: Revert "Make 'bt_sfi_data' const"

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 <andriy.shevche...@linux.intel.com>
Cc: Bhumika Goyal <bhumi...@gmail.com>
Cc: Darren Hart <dvh...@infradead.org>
Cc: Linus Torvalds <torva...@linux-foundation.org>
Cc: Peter Zijlstra <pet...@infradead.org>
Cc: Thomas Gleixner <t...@linutronix.de>
Cc: julia.law...@lip6.fr
Cc: platform-driver-...@vger.kernel.org
Link: 
http://lkml.kernel.org/r/20171228122523.21802-1-andriy.shevche...@linux.intel.com
Signed-off-by: Ingo Molnar <mi...@kernel.org>
---
 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/x86/platform/intel-mid/device_libs/platform_bt.c
index dc036e5..5a0483e 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 *ddata)
        return 0;
 }
 
-static const struct bt_sfi_data tng_bt_sfi_data __initdata = {
+static struct bt_sfi_data tng_bt_sfi_data __initdata = {
        .setup  = tng_bt_sfi_setup,
 };
 

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