diff options
| author | Ard Biesheuvel <ardb@kernel.org> | 2020-01-17 17:43:18 +0100 |
|---|---|---|
| committer | Herbert Xu <herbert@gondor.apana.org.au> | 2020-01-22 16:21:11 +0800 |
| commit | 0bc81767c5bd9d005fae1099fb39eb3688370cb1 (patch) | |
| tree | 46c1f807ad84e7916b567b59ee5ec72f92ce9edf /arch/arm | |
| parent | 7e2b89fb4a2e636ad94fe47b76257c3cc0234666 (diff) | |
crypto: arm/chacha - fix build failured when kernel mode NEON is disabled
When the ARM accelerated ChaCha driver is built as part of a configuration
that has kernel mode NEON disabled, we expect the compiler to propagate
the build time constant expression IS_ENABLED(CONFIG_KERNEL_MODE_NEON) in
a way that eliminates all the cross-object references to the actual NEON
routines, which allows the chacha-neon-core.o object to be omitted from
the build entirely.
Unfortunately, this fails to work as expected in some cases, and we may
end up with a build error such as
chacha-glue.c:(.text+0xc0): undefined reference to `chacha_4block_xor_neon'
caused by the fact that chacha_doneon() has not been eliminated from the
object code, even though it will never be called in practice.
Let's fix this by adding some IS_ENABLED(CONFIG_KERNEL_MODE_NEON) tests
that are not strictly needed from a logical point of view, but should
help the compiler infer that the NEON code paths are unreachable in
those cases.
Fixes: b36d8c09e710c71f ("crypto: arm/chacha - remove dependency on generic ...")
Reported-by: Russell King <linux@armlinux.org.uk>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Diffstat (limited to 'arch/arm')
| -rw-r--r-- | arch/arm/crypto/chacha-glue.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/arch/arm/crypto/chacha-glue.c b/arch/arm/crypto/chacha-glue.c index 6ebbb2b241d2..6fdb0ac62b3d 100644 --- a/arch/arm/crypto/chacha-glue.c +++ b/arch/arm/crypto/chacha-glue.c @@ -115,7 +115,7 @@ static int chacha_stream_xor(struct skcipher_request *req, if (nbytes < walk.total) nbytes = round_down(nbytes, walk.stride); - if (!neon) { + if (!IS_ENABLED(CONFIG_KERNEL_MODE_NEON) || !neon) { chacha_doarm(walk.dst.virt.addr, walk.src.virt.addr, nbytes, state, ctx->nrounds); state[12] += DIV_ROUND_UP(nbytes, CHACHA_BLOCK_SIZE); @@ -159,7 +159,7 @@ static int do_xchacha(struct skcipher_request *req, bool neon) chacha_init_generic(state, ctx->key, req->iv); - if (!neon) { + if (!IS_ENABLED(CONFIG_KERNEL_MODE_NEON) || !neon) { hchacha_block_arm(state, subctx.key, ctx->nrounds); } else { kernel_neon_begin(); |