Commits
Arnd Bergmann committed 72c8117adfc
crypto: ccp - Reduce maximum stack usage
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: 63b945091a07 ("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>