On 3/23/21 6:51 AM, Pavel Begunkov wrote: > On 23/03/2021 11:31, kernel test robot wrote: >> tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git >> master >> head: 84196390620ac0e5070ae36af84c137c6216a7dc >> commit: e5d1bc0a91f16959aa279aa3ee9fdc246d4bb382 io_uring: defer flushing >> cached reqs >> date: 6 weeks ago >> config: powerpc64-randconfig-r023-20210323 (attached as .config) >> compiler: clang version 13.0.0 (https://github.com/llvm/llvm-project >> 14696baaf4c43fe53f738bc292bbe169eed93d5d) >> reproduce (this is a W=1 build): >> wget >> https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O >> ~/bin/make.cross >> chmod +x ~/bin/make.cross >> # install powerpc64 cross compiling tool for clang build >> # apt-get install binutils-powerpc64-linux-gnu >> # >> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=e5d1bc0a91f16959aa279aa3ee9fdc246d4bb382 >> git remote add linus >> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git >> git fetch --no-tags linus master >> git checkout e5d1bc0a91f16959aa279aa3ee9fdc246d4bb382 >> # save the attached .config to linux build tree >> COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross >> ARCH=powerpc64 >> >> If you fix the issue, kindly add following tag as appropriate >> Reported-by: kernel test robot <l...@intel.com> >> >> All warnings (new ones prefixed by >>): >> >>>> fs/io_uring.c:6920:12: warning: stack frame size of 1040 bytes in function >>>> 'io_submit_sqes' [-Wframe-larger-than=] >> static int io_submit_sqes(struct io_ring_ctx *ctx, unsigned int nr) >> ^ >> 1 warning generated. b > > I don't know, for up-to-date code all submission functions are under > 128 bytes for me, including io_submit_sqes with everything heavily > inlined into it. I believe it's just a strange config keeping > everything on stack for some reason (too under optimised?).
Must be the powerpc compiler doing something weird, it's probably inlining io_submit_sqe() and all opcode handlers. And then you get there pretty quick, eg io_recvmsg() uses 768 bytes of stack here. -- Jens Axboe
