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Eric Biggers
572af6872e
The new library APIs for AES encryption modes were wired up to the traditional crypto API via crypto/aes.c. However, for now the kernel is still in a transitional state where various architectures still have architecture-optimized implementations of AES modes in arch/*/crypto/, wired up to the traditional crypto API only. Because of that, the crypto/aes.c algorithms were given a cra_priority of only 110 to prevent them from overriding arch/*/crypto/ in the traditional crypto API. However, because of how the traditional crypto API works, the cra_priority trick doesn't work in cases where the relevant algorithm isn't directly implemented by arch/*/crypto/ but rather is provided by a template instance using other code in arch/*/crypto/. For example, x86 doesn't have its own "ccm(aes)" but rather relies on the "ccm" template constructing it from the x86-optimized "ctr(aes)". The existence of the library-based "ccm(aes)" prevents that, even though its priority is lower than what the template would produce. Thus, "ccm(aes)" ends up using the slower single-block AES code. Therefore, skip wiring up the relevant library-based code to the traditional crypto API on architectures where this problem can occur, as determined by what exists in arch/*/crypto/ for each architecture. This is ugly, but it's also temporary: these conditions will go away as architecture-optimized implementations of AES modes are migrated into the library. But until then, we need to prevent performance regressions by ensuring that the optimized code continues to be used. Fixes:20df21a482("crypto: aes - Add CBC and CBC-CTS support using library") Fixes:8ca62072fa("crypto: aes - Add GCM support using library") Fixes:f70ad727d1("crypto: aes - Add CCM support using library") Fixes:94efa0c9fb("crypto: aes - Add XTS support using library") Closes: https://github.com/sparclinux/issues/issues/106 Acked-by: Ard Biesheuvel <[email protected]> Tested-by: Stian Halseth <[email protected]> Link: https://patch.msgid.link/[email protected] Signed-off-by: Eric Biggers <[email protected]>