[kbuild-all] Re: [linux-stable-rc:linux-5.4.y 665/2391] drivers/android/binder.c:3776: Error: unrecognized keyword/register name `l.lwz

On Fri, Oct 16, 2020, 6:46 AM Jann Horn <jannh(a)google.com&gt; wrote: > +openrisc folks > > On Thu, Oct 15, 2020 at 11:28 PM kernel test robot <lkp(a)intel.com&gt; wrote: > > tree: > https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable-rc.git > linux-5.4.y > > head: 85b0841aab15c12948af951d477183ab3df7de14 > > commit: c5665cafbedd2e2a523fe933e452391a02d3adb3 [665/2391] binder: > Prevent context manager from incrementing ref 0 > > config: openrisc-randconfig-r002-20201014 (attached as .config) > > compiler: or1k-linux-gcc (GCC) 9.3.0 > > 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 > > # > https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable-rc.gi... > > git remote add linux-stable-rc > https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable-rc.git > > git fetch --no-tags linux-stable-rc linux-5.4.y > > git checkout c5665cafbedd2e2a523fe933e452391a02d3adb3 > > # save the attached .config to linux build tree > > COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross > ARCH=openrisc > > > > If you fix the issue, kindly add following tag as appropriate > > Reported-by: kernel test robot <lkp(a)intel.com&gt; > > > > All errors (new ones prefixed by >>): > > > > drivers/android/binder.c: Assembler messages: > > >> drivers/android/binder.c:3776: Error: unrecognized keyword/register > name `l.lwz ?ap,4(r25)' > > drivers/android/binder.c:3781: Error: unrecognized keyword/register > name `l.addi ?ap,r0,0' > > binder is basically doing this: > > u64 data_ptr; > if (get_user(data_ptr, (u64 __user *)ptr)) > return -EFAULT; > > and GCC complains that that doesn't turn into valid assembly on > openrisc, where get_user() of size 8 expands into this: > > #define __get_user_asm2(x, addr, err) \ > { \ > unsigned long long __gu_tmp; \ > __asm__ __volatile__( \ > "1: l.lwz %1,0(%2)\n" \ > "2: l.lwz %H1,4(%2)\n" \ > "3:\n" \ > ".section .fixup,\"ax\"\n" \ > "4: l.addi %0,r0,%3\n" \ > " l.addi %1,r0,0\n" \ > " l.addi %H1,r0,0\n" \ > " l.j 3b\n" \ > " l.nop\n" \ > ".previous\n" \ > ".section __ex_table,\"a\"\n" \ > " .align 2\n" \ > " .long 1b,4b\n" \ > " .long 2b,4b\n" \ > ".previous" \ > : "=r"(err), "=&r"(__gu_tmp) \ > : "r"(addr), "i"(-EFAULT), "0"(err)); \ > (x) = (__typeof__(*(addr)))( \ > (__typeof__((x)-(x)))__gu_tmp); \ > } > > and apparently the "l.lwz %H1,4(%2)" and "l.addi %H1,r0,0" don't turn > into valid assembly when %H1 expands to "?ap"? > > I don't know anything about OpenRISC, but this seems like it's > probably an issue in the get_user() implementation. > This is fixed in 5.9. I think the patch can be cherry picked by itself. https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit...