On Tue, 2020-10-20 at 08:00 +0000, David Laight wrote: > From: Joe Perches > > Sent: 19 October 2020 16:47 > > On Mon, 2020-10-19 at 03:13 +0800, kernel test robot wrote: > > > Hi Ard, > > > > > > First bad commit (maybe != root cause): > > > > > > tree: > > > https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master > > > head: 9d9af1007bc08971953ae915d88dc9bb21344b53 > > > commit: 5fb8ef25803ef33e2eb60b626435828b937bed75 crypto: chacha - move > > > existing library code into > > lib/crypto > > > date: 11 months ago > > > config: i386-randconfig-r023-20201019 (attached as .config) > > > compiler: gcc-9 (Debian 9.3.0-15) 9.3.0 > > > reproduce (this is a W=1 build): > > > # > > https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=5fb8ef25803ef33e2eb60b62 > > 6435828b937bed75 > > > git remote add linus > > > https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git > > > git fetch --no-tags linus master > > > git checkout 5fb8ef25803ef33e2eb60b626435828b937bed75 > > > # save the attached .config to linux build tree > > > make W=1 ARCH=i386 > > > > > > 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 >>): > > > > > > lib/crypto/chacha.c: In function 'chacha_permute': > > > > > lib/crypto/chacha.c:65:1: warning: the frame size of 1604 bytes is > > > > > larger than 1024 bytes [- > > Wframe-larger-than=] > > > 65 | } > > > | ^ > > > > > > vim +65 lib/crypto/chacha.c > > > > This seems to come from function tracing overhead. > > Are you sure?
No. I'm trying to isolate it now. > I've not got the x86 object, but the x86-64 version caches the 16 x[] > values (from the parameter) in registers. > The 32 bit cpu doesn't have enough registers, but gcc tends to > compile assuming an infinite number. > So it may have spilled lots of virtual registers to different > stack locations - instead of writing the values to their 'target' > address.