On Tue, Apr 24, 2018 at 5:40 PM, Will Deacon will.deacon@arm.com wrote:
On Tue, Apr 24, 2018 at 03:43:04PM +0200, Jason A. Donenfeld wrote:
On Tue, Apr 24, 2018 at 3:34 PM, Will Deacon will.deacon@arm.com wrote:
I've not run into any build issues here -- is this specifically with some out-of-tree module?
I received a bug report email about this. I'm not sure which specific module, and I assumed from the email that it was actually a result of in-tree configuration options rather than an out-of-tree module, but I'm not sure exactly. Either way, I was able to reproduce the problem by coding up a little PoC out-of-tree module, so it is certainly a real problem.
Any chance you could share the module, please? I tried to write one but the compiler just inlines the __in128 arithmetic.
Sure. I didn't save my original but just cooked a new one up and verified it errors out. The below will get these errors on mainline when compiled as a module, even as an in-tree module:
ERROR: "__lshrti3" [uhohspehgettio.ko] undefined! ERROR: "__ashlti3" [uhohspehgettio.ko.ko] undefined!
#include <linux/module.h>
__uint128_t global1, global2; __uint128_t addrs[8];
void do_something(__uint128_t a, unsigned int idx) { addrs[idx] = a; }
static int __init mod_init(void) { do_something(global1 >> global2, (global2 << global1) & 7); return 0; }
module_init(mod_init); MODULE_LICENSE("GPL v2");