Hi Paul,
On Fri, 2023-08-11 at 08:41 -0700, Paul E. McKenney wrote:
On Fri, Aug 11, 2023 at 01:02:12PM +0800, kernel test robot wrote:
tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
master
head: 25aa0bebba72b318e71fe205bfd1236550cc9534
commit: a6889becb05394255c80b62103677e3b095726a9 refscale: Add tests using
SLAB_TYPESAFE_BY_RCU
date: 7 months ago
config: arc-randconfig-r006-20230811
(https://download.01.org/0day-ci/archive/20230811/202308111233.rbf5c0jd-...@intel.com/config)
compiler: arceb-elf-gcc (GCC) 12.3.0
reproduce:
(https://download.01.org/0day-ci/archive/20230811/202308111233.rbf5c0jd-...@intel.com/reproduce)
If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
Reported-by: kernel test robot <l...@intel.com>
Closes:
https://lore.kernel.org/oe-kbuild-all/202308111233.rbf5c0jd-...@intel.com/
All errors (new ones prefixed by >>):
{standard input}: Assembler messages:
{standard input}:1727: Error: operand out of range (-132 is not between -128
and 127)
I am not seeing any inline assembly in that patch, so I have to suspect
a bug in arch code or the compiler backend for arc.
Or is there something that I am missing here?
We looked into this case a little bit. The assembler error popped up
when building kernel/rcu/refscale.o
$make W=1 --keep-going CROSS_COMPILE=arceb-elf- ARCH=arc kernel/rcu/refscale.o
...
CC [M] kernel/rcu/refscale.o
{standard input}: Assembler messages:
{standard input}:1727: Error: operand out of range (-132 is not between -128
and 127)
make[3]: *** [scripts/Makefile.build:252: kernel/rcu/refscale.o] Error 1
make[2]: *** [scripts/Makefile.build:504: kernel/rcu] Error 2
make[2]: Target 'kernel/rcu/refscale.o' not remade because of errors.
make[1]: *** [scripts/Makefile.build:504: kernel] Error 2
make[1]: Target 'kernel/rcu/refscale.o' not remade because of errors.
make: *** [Makefile:2008: .] Error 2
make: Target 'kernel/rcu/refscale.o' not remade because of errors.
We did some assembly and disassembly tricks:
1721 .L334:
1722 ld_s r0,[r14,52] ;15
1723 brgt r0, r19, @.L335
1724 ld_s r0,[r13,120] ;15
1725 breq_s r0, 0, @.L337
1726 jl [r17]
1727 brne_s r0, 0, @.L337 <---
1728 mov_s r2,20 ;3
1729 mov_s r1,0 ;3
1730 mov_s r0,sp ;4
1731 jl [r20]
1732 mov_s r1,0 ;3
1733 mov_s r0,sp ;4
1734 jl @init_wait_entry
1735 .align 2
This assembly instruction at line 1727 points to the code in main_func,
but main_func is not touched by commit a6889becb053.
d6e: 860d ld_s r0,[r14,0x34]
d70: 0b59 a002 brlt.nt r19,r0,-168 ;cc8 <main_func+0x16c>
return arch_atomic_read(v);
d74: 851e ld_s r0,[r13,0x78]
wait_event(main_wq,
d76: e842 breq_s r0,0,-124 ;cf8 <main_func+0x19c>
d78: 2022 0440 jl [r17]
d7c: e8be brne_s r0,0,124 ;df8 <main_func+0x29c>
<--
d7e: da14 mov_s r2,0x14
d80: 702c mov_s r1,0
d82: 4083 mov_s r0,sp
d84: 2022 0500 jl [r20]
d88: 702c mov_s r1,0
d8a: 4083 mov_s r0,sp
d8c: 2022 0f80 0000 0000 jl 0
We also tried on the parent commit 3c6496c86e48. It builds fine without
that assembler error, and corresponding disassembly is:
afe: 860d ld_s r0,[r14,0x34]
b00: 0b5d a002 brlt.nt r19,r0,-164 ;a5c <main_func+0x16c>
return arch_atomic_read(v);
b04: 8518 ld_s r0,[r13,0x60]
wait_event(main_wq,
b06: e844 breq_s r0,0,-120 ;a8c <main_func+0x19c>
b08: 2022 0440 jl [r17]
b0c: e8c0 brne_s r0,0,-128 ;a8c <main_func+0x19c>
<--
b0e: da14 mov_s r2,0x14
b10: 702c mov_s r1,0
b12: 4083 mov_s r0,sp
b14: 2022 0500 jl [r20]
b18: 702c mov_s r1,0
b1a: 4083 mov_s r0,sp
b1c: 2022 0f80 0000 0000 jl 0
b24: 724c mov_s r2,2
b26: 4183 mov_s r1,sp
b28: 40c3 0000 0000 mov_s r0,0
b2e: 2022 0f80 0000 0000 jl 0
We are also not sure if this is a bug in arch code or compiler side.
Here we provide above info for your reference.
