On 17/05/2019 11.41, Vitaly Kuznetsov wrote:
Peter Xu peterx@redhat.com writes:
On Fri, May 17, 2019 at 11:04:45AM +0200, Thomas Huth wrote:
So far the KVM selftests are compiled without any compiler warnings enabled. That's quite bad, since we miss a lot of possible bugs this way. Let's enable at least "-Wall" and some other useful warning flags now, and fix at least the trivial problems in the code (like unused variables).
Signed-off-by: Thomas Huth thuth@redhat.com
v2:
- Rebased to kvm/queue
- Fix warnings in state_test.c and evmcs_test.c, too
I still see these warnings (probably because the hyperv_cpuid.c is a new test):
In file included from x86_64/hyperv_cpuid.c:18: x86_64/hyperv_cpuid.c: In function ‘test_hv_cpuid’: x86_64/hyperv_cpuid.c:61:33: warning: suggest parentheses around comparison in operand of ‘==’ [-Wparentheses] TEST_ASSERT(entry->padding[0] == entry->padding[1] ~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~ include/test_util.h:32:15: note: in definition of macro ‘TEST_ASSERT’ test_assert((e), #e, __FILE__, __LINE__, fmt, ##__VA_ARGS__) ^ x86_64/hyperv_cpuid.c:62:8: warning: suggest parentheses around comparison in operand of ‘==’ [-Wparentheses] TEST_ASSERT(entry->padding[0] == entry->padding[1] ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ == entry->padding[2] == 0, ^~~~~~~~~~~~~~~~~~~~ include/test_util.h:32:15: note: in definition of macro ‘TEST_ASSERT’ test_assert((e), #e, __FILE__, __LINE__, fmt, ##__VA_ARGS__)
There's a fix from Dan Carpenter on the list: https://marc.info/?l=kernel-janitors&m=155783012012532&w=2
Right, that fix should preferably be committed first.
x86_64/hyperv_cpuid.c: In function ‘kvm_get_supported_hv_cpuid’: x86_64/hyperv_cpuid.c:93:6: warning: unused variable ‘ret’ [-Wunused-variable] int ret; ^~~
... but I obviously missed this one here again :-/
There are also these compiler warnings left:
lib/ucall.c: In function ‘get_ucall’: lib/ucall.c:145:3: warning: dereferencing type-punned pointer will break strict-aliasing rules [-Wstrict-aliasing] gva = *(vm_vaddr_t *)run->mmio.data;
x86_64/vmx_set_nested_state_test.c: In function ‘set_revision_id_for_vmcs12’: x86_64/vmx_set_nested_state_test.c:78:2: warning: dereferencing type-punned pointer will break strict-aliasing rules [-Wstrict-aliasing] *(u32 *)(state->data) = vmcs12_revision;
... how do we want to handle such spots in the kvm selftest code? Compile with -fno-strict-aliasing? Or fix it with type-punning through unions?
Thomas