On Tue, Mar 03, 2020 at 02:43:27PM -0800, Eric Biggers wrote:
> Probably the request_module() is coming from the registration-time crypto
> self-tests allocating the generic implementation of algorithm when an
> architecture-specific implementation is registered. This occurs when
> CONFIG_CRYPTO_MANAGER_EXTRA_TESTS=y on Linux v5.2 and later.
Ok, I can confirm that if we get the debug output from one of Corentin's
boards.
> If this is causing problems we could do:
>
> diff --git a/crypto/testmgr.c b/crypto/testmgr.c
> index ccb3d60729fc..d89791700b88 100644
> --- a/crypto/testmgr.c
> +++ b/crypto/testmgr.c
> @@ -1667,7 +1667,7 @@ static int test_hash_vs_generic_impl(const char *driver,
> if (strcmp(generic_driver, driver) == 0) /* Already the generic impl? */
> return 0;
>
> - generic_tfm = crypto_alloc_shash(generic_driver, 0, 0);
> + generic_tfm = crypto_alloc_shash(generic_driver, 0, CRYPTO_NOLOAD);
> if (IS_ERR(generic_tfm)) {
> err = PTR_ERR(generic_tfm);
> if (err == -ENOENT) {
> @@ -2389,7 +2389,7 @@ static int test_aead_vs_generic_impl(struct aead_extra_tests_ctx *ctx)
> if (strcmp(generic_driver, driver) == 0) /* Already the generic impl? */
> return 0;
>
> - generic_tfm = crypto_alloc_aead(generic_driver, 0, 0);
> + generic_tfm = crypto_alloc_aead(generic_driver, 0, CRYPTO_NOLOAD);
> if (IS_ERR(generic_tfm)) {
> err = PTR_ERR(generic_tfm);
> if (err == -ENOENT) {
> @@ -2993,7 +2993,7 @@ static int test_skcipher_vs_generic_impl(const char *driver,
> if (strcmp(generic_driver, driver) == 0) /* Already the generic impl? */
> return 0;
>
> - generic_tfm = crypto_alloc_skcipher(generic_driver, 0, 0);
> + generic_tfm = crypto_alloc_skcipher(generic_driver, 0, CRYPTO_NOLOAD);
> if (IS_ERR(generic_tfm)) {
> err = PTR_ERR(generic_tfm);
> if (err == -ENOENT) {
>
>
> ... but that's not ideal, since it would mean that if someone builds all crypto
> algorithms as modules, then the comparison tests could be unnecessarily skipped.
We should try to avoid this then.
> But it is really always wrong to be calling request_module() from other
> module_init() functions? The commit that added 'init_free_wq' was also
> introduced in v5.2; maybe that's the problem here?
>
> commit 1a7b7d9220819afe79d1ec5d759fe4349bd2453e
> Author: Rick Edgecombe <rick.p.edgecombe@xxxxxxxxx>
> Date: Thu Apr 25 17:11:37 2019 -0700
>
> modules: Use vmalloc special flag
Yes, I don't see a reason init_free_wq has to be initialized that late.
