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| author | Victor Kamensky <victor.kamensky@linaro.org> | 2013-08-08 20:37:03 -0700 |
|---|---|---|
| committer | Riku Voipio <riku.voipio@linaro.org> | 2013-08-20 10:09:59 +0300 |
| commit | 287759ed7af0d2b2d3dadc5ed87d6b4c72f215ff (patch) | |
| tree | cbcb5547d9e24babbacf19ce3ba4f4b757bb5f63 | |
| parent | fc8bf09a48c6e220350727814d2c49d45c80dbf2 (diff) | |
python libffi: fix arm trampoline to work on arm v7 big endian (be8) case
Since python source base has its own copy of libffi, it fixes the issue
here. Note similar fix is committed into separate libffi library.
cffi code creates trampoline for python callback function, which is
supposed to be called from another C function and it does not take into
account that in ARMv7a in big endian mode instructions are still in
little endian. Since written by big endian code they have to be
byteswapped. Proposed fix uses byteswap codes for instructions.
Here is python code snippet that will fail when libffi is used by
ctypes in python code (func1 and func2 are C functions):
from ctypes import *
mylib = CDLL("libmytest.so")
func1 = mylib.func1
print func1(1, 2)
CBFUNC = CFUNCTYPE(c_int, c_int, c_int)
def myfunc2(a, b):
return a * a + b * b
cb_func = CBFUNC(myfunc2)
func2 = mylib.func2
print func2(cb_func, 1, 2)
code will produce illegal instruction when func2 will call myfunc2
through trampoline
Signed-off-by: Victor Kamensky <victor.kamensky@linaro.org>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
| -rw-r--r-- | meta-bigendian/recipes-devtools/python/python/python_ffi_armeb_be8.patch | 34 | ||||
| -rw-r--r-- | meta-bigendian/recipes-devtools/python/python_2.7.3.bbappend | 3 |
2 files changed, 37 insertions, 0 deletions
diff --git a/meta-bigendian/recipes-devtools/python/python/python_ffi_armeb_be8.patch b/meta-bigendian/recipes-devtools/python/python/python_ffi_armeb_be8.patch new file mode 100644 index 00000000..afd090b5 --- /dev/null +++ b/meta-bigendian/recipes-devtools/python/python/python_ffi_armeb_be8.patch @@ -0,0 +1,34 @@ +Index: Python-2.7.3/Modules/_ctypes/libffi/src/arm/ffi.c +=================================================================== +--- Python-2.7.3.orig/Modules/_ctypes/libffi/src/arm/ffi.c ++++ Python-2.7.3/Modules/_ctypes/libffi/src/arm/ffi.c +@@ -272,7 +272,7 @@ ffi_prep_incoming_args_SYSV(char *stack, + } + + /* How to make a trampoline. */ +- ++#if !(defined(__ARMEB__) && defined(__ARM_ARCH_7A__)) + #define FFI_INIT_TRAMPOLINE(TRAMP,FUN,CTX) \ + ({ unsigned char *__tramp = (unsigned char*)(TRAMP); \ + unsigned int __fun = (unsigned int)(FUN); \ +@@ -284,7 +284,19 @@ ffi_prep_incoming_args_SYSV(char *stack, + *(unsigned int*) &__tramp[16] = __fun; \ + __clear_cache((&__tramp[0]), (&__tramp[19])); \ + }) +- ++#else /* armv7 big endian: be8 instructions are still little endian */ ++#define FFI_INIT_TRAMPOLINE(TRAMP,FUN,CTX) \ ++({ unsigned char *__tramp = (unsigned char*)(TRAMP); \ ++ unsigned int __fun = (unsigned int)(FUN); \ ++ unsigned int __ctx = (unsigned int)(CTX); \ ++ *(unsigned int*) &__tramp[0] = 0x0f002de9; /* swab(0xe92d000f, 4) - stmfd sp!, {r0-r3} */ \ ++ *(unsigned int*) &__tramp[4] = 0x00009fe5; /* swab(0xe59f0000, 4) - ldr r0, [pc] */ \ ++ *(unsigned int*) &__tramp[8] = 0x00f09fe5; /* swab(0xe59ff000, 4) - ldr pc, [pc] */ \ ++ *(unsigned int*) &__tramp[12] = __ctx; \ ++ *(unsigned int*) &__tramp[16] = __fun; \ ++ __clear_cache((&__tramp[0]), (&__tramp[19])); \ ++ }) ++#endif + + /* the cif must already be prep'ed */ + diff --git a/meta-bigendian/recipes-devtools/python/python_2.7.3.bbappend b/meta-bigendian/recipes-devtools/python/python_2.7.3.bbappend new file mode 100644 index 00000000..a3dfa9bd --- /dev/null +++ b/meta-bigendian/recipes-devtools/python/python_2.7.3.bbappend @@ -0,0 +1,3 @@ +FILESEXTRAPATHS := "${THISDIR}/${PN}" + +SRC_URI += "file://python_ffi_armeb_be8.patch" |