Re: [PATCH] KVM: selftests: Fix core dump in rseq_test

[Gavin Shan]

Hi Sean,

On 11/24/25 3:04 PM, Gavin Shan wrote:

In commit 0297cdc12a87 ("KVM: selftests: Add option to rseq test to
override /dev/cpu_dma_latency"), a 'break' is missed before the option
'l' in the argument parsing loop, which leads to an unexpected core
dump in atoi_paranoid(). It tries to get the latency from non-existent
argument.

   host$ ./rseq_test -u
   Random seed: 0x6b8b4567
   Segmentation fault (core dumped)

Add a 'break' before the option 'l' in the argument parsing loop to avoid
the unexpected core dump.

Fixes: 0297cdc12a87 ("KVM: selftests: Add option to rseq test to override 
/dev/cpu_dma_latency")
Cc: sta...@vger.kernel.org # v6.15+
Signed-off-by: Gavin Shan <gs...@redhat.com>
---
  tools/testing/selftests/kvm/rseq_test.c | 1 +
  1 file changed, 1 insertion(+)

Could you help to take a look when getting a chance? :)

Thanks,
Gavin

diff --git a/tools/testing/selftests/kvm/rseq_test.c 
b/tools/testing/selftests/kvm/rseq_test.c
index 1375fca80bcdb..f80ad6b47d16b 100644
--- a/tools/testing/selftests/kvm/rseq_test.c
+++ b/tools/testing/selftests/kvm/rseq_test.c
@@ -215,6 +215,7 @@ int main(int argc, char *argv[])
                switch (opt) {
                case 'u':
                        skip_sanity_check = true;
+                       break;
                case 'l':
                        latency = atoi_paranoid(optarg);
                        break;