On 21/09/21 09:19, Andrew Jones wrote:
On Tue, Sep 21, 2021 at 01:01:20AM +0000, Oliver Upton wrote:
Building steal_time.c for arm64 with clang throws the following:
steal_time.c:130:22: error: value size does not match register size specified by the constraint and modifier [-Werror,-Wasm-operand-widths]
: "=r" (ret) : "r" (func), "r" (arg) :
^
steal_time.c:130:34: error: value size does not match register size specified by the constraint and modifier [-Werror,-Wasm-operand-widths]
: "=r" (ret) : "r" (func), "r" (arg) :
^
Silence by casting operands to 64 bits.
Signed-off-by: Oliver Upton <oupton@xxxxxxxxxx>
---
tools/testing/selftests/kvm/steal_time.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/tools/testing/selftests/kvm/steal_time.c b/tools/testing/selftests/kvm/steal_time.c
index ecec30865a74..eb75b31122c5 100644
--- a/tools/testing/selftests/kvm/steal_time.c
+++ b/tools/testing/selftests/kvm/steal_time.c
@@ -127,7 +127,7 @@ static int64_t smccc(uint32_t func, uint32_t arg)
"mov x1, %2\n"
"hvc #0\n"
"mov %0, x0\n"
- : "=r" (ret) : "r" (func), "r" (arg) :
+ : "=r" (ret) : "r" ((uint64_t)func), "r" ((uint64_t)arg) :
Actually, I think I'd rather fix this smccc implementation to match the
spec, which I think should be done like this
diff --git a/tools/testing/selftests/kvm/steal_time.c b/tools/testing/selftests/kvm/steal_time.c
index ecec30865a74..7da957259ce4 100644
--- a/tools/testing/selftests/kvm/steal_time.c
+++ b/tools/testing/selftests/kvm/steal_time.c
@@ -118,12 +118,12 @@ struct st_time {
uint64_t st_time;
};
-static int64_t smccc(uint32_t func, uint32_t arg)
+static int64_t smccc(uint32_t func, uint64_t arg)
{
unsigned long ret;
asm volatile(
- "mov x0, %1\n"
+ "mov w0, %w1\n"
"mov x1, %2\n"
"hvc #0\n"
"mov %0, x0\n"
Agreed, can you send out a patch? Thanks,
Paolo
