I tried to test the fix to 32-bit poweroc boot hang but found that current git does not compile on 32bit poweroc at all for me:
CC arch/powerpc/kernel/ptrace.o
In file included from ./include/linux/bitmap.h:9,
from ./include/linux/cpumask.h:12,
from ./include/linux/rcupdate.h:44,
from ./include/linux/rculist.h:11,
from ./include/linux/pid.h:5,
from ./include/linux/sched.h:14,
from arch/powerpc/kernel/ptrace.c:19:
In function ‘memcpy’,
inlined from ‘user_regset_copyin’ at ./include/linux/regset.h:295:4,
inlined from ‘vr_set’ at arch/powerpc/kernel/ptrace.c:619:9:
./include/linux/string.h:345:9: error: ‘__builtin_memcpy’ offset [-527, -529] is out of the bounds [0, 16] of object ‘vrsave’ with type ‘union <anonymous>’ [-Werror=array-bounds]
return __builtin_memcpy(p, q, size);
^~~~~~~~~~~~~~~~~~~~~~~~~~~~
arch/powerpc/kernel/ptrace.c: In function ‘vr_set’:
arch/powerpc/kernel/ptrace.c:614:5: note: ‘vrsave’ declared here
} vrsave;
^~~~~~
In file included from ./include/linux/bitmap.h:9,
from ./include/linux/cpumask.h:12,
from ./include/linux/rcupdate.h:44,
from ./include/linux/rculist.h:11,
from ./include/linux/pid.h:5,
from ./include/linux/sched.h:14,
from arch/powerpc/kernel/ptrace.c:19:
In function ‘memcpy’,
inlined from ‘user_regset_copyout’ at ./include/linux/regset.h:270:4,
inlined from ‘vr_get’ at arch/powerpc/kernel/ptrace.c:572:9:
./include/linux/string.h:345:9: error: ‘__builtin_memcpy’ offset [-527, -529] is out of the bounds [0, 16] of object ‘vrsave’ with type ‘union <anonymous>’ [-Werror=array-bounds]
return __builtin_memcpy(p, q, size);
^~~~~~~~~~~~~~~~~~~~~~~~~~~~
arch/powerpc/kernel/ptrace.c: In function ‘vr_get’:
arch/powerpc/kernel/ptrace.c:567:5: note: ‘vrsave’ declared here
} vrsave;
^~~~~~
cc1: all warnings being treated as errors
make[1]: *** [scripts/Makefile.build:306: arch/powerpc/kernel/ptrace.o] Error 1
make: *** [Makefile:1052: arch/powerpc/kernel] Error 2
--
Meelis Roos [off-list ref]
Meelis Roos [off-list ref] writes:
I tried to test the fix to 32-bit poweroc boot hang but found that current git does not compile on 32bit poweroc at all for me:
That's GCC 8 I think?
I have seen that but couldn't work out what the hell GCC is thinking.
I don't think there's an actual bug, the size of the copy is bounded by
the count parameter, which *doesn't* come from user space, it's hard
coded.
I suspect the logic is just to convoluted for GCC.
We should fix it somehow, but I haven't worked out what's the best option.
cheers
CC arch/powerpc/kernel/ptrace.o
In file included from ./include/linux/bitmap.h:9,
from ./include/linux/cpumask.h:12,
from ./include/linux/rcupdate.h:44,
from ./include/linux/rculist.h:11,
from ./include/linux/pid.h:5,
from ./include/linux/sched.h:14,
from arch/powerpc/kernel/ptrace.c:19:
In function ‘memcpy’,
inlined from ‘user_regset_copyin’ at ./include/linux/regset.h:295:4,
inlined from ‘vr_set’ at arch/powerpc/kernel/ptrace.c:619:9:
./include/linux/string.h:345:9: error: ‘__builtin_memcpy’ offset [-527, -529] is out of the bounds [0, 16] of object ‘vrsave’ with type ‘union <anonymous>’ [-Werror=array-bounds]
return __builtin_memcpy(p, q, size);
^~~~~~~~~~~~~~~~~~~~~~~~~~~~
arch/powerpc/kernel/ptrace.c: In function ‘vr_set’:
arch/powerpc/kernel/ptrace.c:614:5: note: ‘vrsave’ declared here
} vrsave;
^~~~~~
In file included from ./include/linux/bitmap.h:9,
from ./include/linux/cpumask.h:12,
from ./include/linux/rcupdate.h:44,
from ./include/linux/rculist.h:11,
from ./include/linux/pid.h:5,
from ./include/linux/sched.h:14,
from arch/powerpc/kernel/ptrace.c:19:
In function ‘memcpy’,
inlined from ‘user_regset_copyout’ at ./include/linux/regset.h:270:4,
inlined from ‘vr_get’ at arch/powerpc/kernel/ptrace.c:572:9:
./include/linux/string.h:345:9: error: ‘__builtin_memcpy’ offset [-527, -529] is out of the bounds [0, 16] of object ‘vrsave’ with type ‘union <anonymous>’ [-Werror=array-bounds]
return __builtin_memcpy(p, q, size);
^~~~~~~~~~~~~~~~~~~~~~~~~~~~
arch/powerpc/kernel/ptrace.c: In function ‘vr_get’:
arch/powerpc/kernel/ptrace.c:567:5: note: ‘vrsave’ declared here
} vrsave;
^~~~~~
cc1: all warnings being treated as errors
make[1]: *** [scripts/Makefile.build:306: arch/powerpc/kernel/ptrace.o] Error 1
make: *** [Makefile:1052: arch/powerpc/kernel] Error 2
--
Meelis Roos [off-list ref]
quoted
I tried to test the fix to 32-bit poweroc boot hang but found that current git does not compile on 32bit poweroc at all for me:
That's GCC 8 I think?
Yes, gcc version 8.2.0 (Debian 8.2.0-7).
I have seen that but couldn't work out what the hell GCC is thinking.
I don't think there's an actual bug, the size of the copy is bounded by
the count parameter, which *doesn't* come from user space, it's hard
coded.
I suspect the logic is just to convoluted for GCC.
We should fix it somehow, but I haven't worked out what's the best option.
cheers
--
Meelis Roos [off-list ref]