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charset="utf-8" Passing num_mb=3D0 to the multibuffer speed tests leaves test_mb_aead_cycle= s() and test_mb_acipher_cycles() dividing by (8 * num_mb). With sec=3D0 (the default), the module prints "1 operation in ..." and hits a divide-by-zero fault. Force num_mb to at least 1 during module init and warn the caller so the warm-up loop and the final report stay well-defined. To reproduce: sudo modprobe tcrypt mode=3D600 num_mb=3D0 Signed-off-by: Saeed Mirzamohammadi --- crypto/tcrypt.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/crypto/tcrypt.c b/crypto/tcrypt.c index aded375461374..61c8cf55c4f1e 100644 --- a/crypto/tcrypt.c +++ b/crypto/tcrypt.c @@ -2808,6 +2808,11 @@ static int __init tcrypt_mod_init(void) goto err_free_tv; } =20 + if (!num_mb) { + pr_warn("num_mb must be at least 1; forcing to 1\n"); + num_mb =3D 1; + } + err =3D do_test(alg, type, mask, mode, num_mb); =20 if (err) { --=20 2.50.1