From: Alessandro Zanni Date: Wed, 24 Sep 2025 17:16:28 +0000 (+0200) Subject: iommu/selftest: prevent use of uninitialized variable X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=1d235d8494259b588bc3b7d29bc73ce34bf885bc;p=thirdparty%2Fkernel%2Fstable.git iommu/selftest: prevent use of uninitialized variable Fix to avoid the usage of the `res` variable uninitialized in the following macro expansions. It solves the following warning: In function ‘iommufd_viommu_vdevice_alloc’, inlined from ‘wrapper_iommufd_viommu_vdevice_alloc’ at iommufd.c:2889:1: ../kselftest_harness.h:760:12: warning: ‘ret’ may be used uninitialized [-Wmaybe-uninitialized] 760 | if (!(__exp _t __seen)) { \ | ^ ../kselftest_harness.h:513:9: note: in expansion of macro ‘__EXPECT’ 513 | __EXPECT(expected, #expected, seen, #seen, ==, 1) | ^~~~~~~~ iommufd_utils.h:1057:9: note: in expansion of macro ‘ASSERT_EQ’ 1057 | ASSERT_EQ(0, _test_cmd_trigger_vevents(self->fd, dev_id, nvevents)) | ^~~~~~~~~ iommufd.c:2924:17: note: in expansion of macro ‘test_cmd_trigger_vevents’ 2924 | test_cmd_trigger_vevents(dev_id, 3); | ^~~~~~~~~~~~~~~~~~~~~~~~ The issue can be reproduced, building the tests, with the command: make -C tools/testing/selftests TARGETS=iommu Link: https://patch.msgid.link/r/20250924171629.50266-1-alessandro.zanni87@gmail.com Fixes: 97717a1f283f ("iommufd/selftest: Add IOMMU_VEVENTQ_ALLOC test coverage") Signed-off-by: Alessandro Zanni Signed-off-by: Jason Gunthorpe --- diff --git a/tools/testing/selftests/iommu/iommufd_utils.h b/tools/testing/selftests/iommu/iommufd_utils.h index 3c3e08b8c90eb..772ca1db6e597 100644 --- a/tools/testing/selftests/iommu/iommufd_utils.h +++ b/tools/testing/selftests/iommu/iommufd_utils.h @@ -1042,15 +1042,13 @@ static int _test_cmd_trigger_vevents(int fd, __u32 dev_id, __u32 nvevents) .dev_id = dev_id, }, }; - int ret; while (nvevents--) { - ret = ioctl(fd, _IOMMU_TEST_CMD(IOMMU_TEST_OP_TRIGGER_VEVENT), - &trigger_vevent_cmd); - if (ret < 0) + if (!ioctl(fd, _IOMMU_TEST_CMD(IOMMU_TEST_OP_TRIGGER_VEVENT), + &trigger_vevent_cmd)) return -1; } - return ret; + return 0; } #define test_cmd_trigger_vevents(dev_id, nvevents) \