Hi! On Fri, Jan 12, 2018 at 03:55:47PM +0100, Arnd Bergmann wrote: > > crypto/aes_generic.o: In function `crypto_aes_set_key': > >>> aes_generic.c:(.text+0x4e0): undefined reference to `_restgpr_31_x' > > adding linuxpcc-dev to Cc, maybe someone knows a way out of this. > It appears related to https://gcc.gnu.org/bugzilla/show_bug.cgi?id=43810 It is not. > but I don't know what _restgpr_31_x actually does, It restores GPR31 from stack, restores LR from stack, and returns (_x is "exit"). > why it's not provided by the kernel Because the kernel refuses to use libgcc. Let's, uh, not start that again? :-) > or why the aes_generic implementation needs this on > powerpc when built with 'gcc -Os'. FWIW, the -Os change was needed > to work around a possible kernel stack overflow that can happen with > gcc-7.2, see https://patchwork.kernel.org/patch/10143607/ and > https://gcc.gnu.org/bugzilla/show_bug.cgi?id=83356 The _x versions are smaller but slower; that's why they are used with -Os. Apparently nothing else was built with -Os (and the other needed flags) before. Segher
