crypto: ccp - Reduce maximum stack usage
[ Upstream commit 72c8117a ] Each of the operations in ccp_run_cmd() needs several hundred bytes of kernel stack. Depending on the inlining, these may need separate stack slots that add up to more than the warning limit, as shown in this clang based build: drivers/crypto/ccp/ccp-ops.c:871:12: error: stack frame size of 1164 bytes in function 'ccp_run_aes_cmd' [-Werror,-Wframe-larger-than=] static int ccp_run_aes_cmd(struct ccp_cmd_queue *cmd_q, struct ccp_cmd *cmd) The problem may also happen when there is no warning, e.g. in the ccp_run_cmd()->ccp_run_aes_cmd()->ccp_run_aes_gcm_cmd() call chain with over 2000 bytes. Mark each individual function as 'noinline_for_stack' to prevent this from happening, and move the calls to the two special cases for aes into the top-level function. This will keep the actual combined stack usage to the mimimum: 828 bytes for ccp_run_aes_gcm_cmd() and at most 524 bytes for each of the other cases. Fixes: 63b94509 ("crypto: ccp - CCP device driver and interface support") Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Sasha Levin <sashal@kernel.org>
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