From: Andy Shevchenko andriy.shevchenko@linux.intel.com
[ 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 andriy.shevchenko@linux.intel.com Cc: Bhumika Goyal bhumirks@gmail.com Cc: Darren Hart dvhart@infradead.org Cc: Linus Torvalds torvalds@linux-foundation.org Cc: Peter Zijlstra peterz@infradead.org Cc: Thomas Gleixner tglx@linutronix.de Cc: julia.lawall@lip6.fr Cc: platform-driver-x86@vger.kernel.org Link: http://lkml.kernel.org/r/20171228122523.21802-1-andriy.shevchenko@linux.inte... Signed-off-by: Ingo Molnar mingo@kernel.org Signed-off-by: Sasha Levin alexander.levin@microsoft.com --- 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 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 *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, };