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Fix the endian issue once and for all.
The GDB stub returned and the rmemory values are all in the endianess of the arch. Now they are normalize accordingly.
1 parent fe9340b commit 3dc6e18

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6 files changed

+88
-64
lines changed

6 files changed

+88
-64
lines changed

‎contrib/plugins/bap-tracing/frame_buffer.c

Lines changed: 9 additions & 57 deletions
Original file line numberDiff line numberDiff line change
@@ -257,59 +257,9 @@ OperandInfo *frame_init_reg_operand_info(const char *name, const uint8_t *value,
257257
return oi;
258258
}
259259

260-
static size_t mval_type_to_int(enum qemu_plugin_mem_value_type type) {
261-
switch (type) {
262-
case QEMU_PLUGIN_MEM_VALUE_U8:
263-
return 8;
264-
case QEMU_PLUGIN_MEM_VALUE_U16:
265-
return 16;
266-
case QEMU_PLUGIN_MEM_VALUE_U32:
267-
return 32;
268-
case QEMU_PLUGIN_MEM_VALUE_U64:
269-
return 64;
270-
case QEMU_PLUGIN_MEM_VALUE_U128:
271-
return 128;
272-
default:
273-
g_assert(false);
274-
}
275-
return 0;
276-
}
277-
278-
static void mval_to_buf(qemu_plugin_mem_value *val, uint8_t *buf) {
279-
switch (val->type) {
280-
case QEMU_PLUGIN_MEM_VALUE_U8:
281-
buf[0] = val->data.u8;
282-
return;
283-
case QEMU_PLUGIN_MEM_VALUE_U16:
284-
buf[0] = (uint8_t)val->data.u16;
285-
buf[1] = (uint8_t)(val->data.u16 >> 8);
286-
return;
287-
case QEMU_PLUGIN_MEM_VALUE_U32:
288-
buf[0] = (uint8_t)val->data.u32;
289-
buf[1] = (uint8_t)(val->data.u32 >> 8);
290-
buf[2] = (uint8_t)(val->data.u32 >> 16);
291-
buf[3] = (uint8_t)(val->data.u32 >> 24);
292-
return;
293-
case QEMU_PLUGIN_MEM_VALUE_U64:
294-
for (size_t i = 0; i < 8; ++i) {
295-
buf[i] = (uint8_t)(val->data.u64 >> (i * 8));
296-
}
297-
return;
298-
case QEMU_PLUGIN_MEM_VALUE_U128:
299-
for (size_t i = 0; i < 8; ++i) {
300-
buf[i] = (uint8_t)(val->data.u128.low >> (i * 8));
301-
}
302-
for (size_t i = 0; i < 8; ++i) {
303-
buf[i + 8] = (uint8_t)(val->data.u128.high >> (i * 8));
304-
}
305-
return;
306-
default:
307-
g_assert(false);
308-
}
309-
}
310-
311260
static OperandInfo *frame_init_mem_operand_info(uint64_t vaddr,
312-
qemu_plugin_mem_value *mval,
261+
const uint8_t *mval,
262+
size_t mval_bits,
313263
bool is_store) {
314264
MemOperand *ro = g_new(MemOperand, 1);
315265
mem_operand__init(ro);
@@ -319,26 +269,28 @@ static OperandInfo *frame_init_mem_operand_info(uint64_t vaddr,
319269
operand_info_specific__init(ois);
320270
ois->mem_operand = ro;
321271

322-
size_t byte_width = mval_type_to_int(mval->type) / 8;
272+
size_t byte_width = mval_bits / 8;
323273
OperandUsage *ou = g_new(OperandUsage, 1);
324274
operand_usage__init(ou);
325275
ou->read = !is_store;
326276
ou->written = is_store;
327277
OperandInfo *oi = g_new(OperandInfo, 1);
328278
operand_info__init(oi);
329-
oi->bit_length = mval_type_to_int(mval->type);
279+
oi->bit_length = mval_bits;
330280
oi->operand_info_specific = ois;
331281
oi->operand_usage = ou;
332282
oi->value.len = byte_width;
333283
oi->value.data = g_malloc(oi->value.len);
334-
mval_to_buf(mval, oi->value.data);
284+
memcpy(oi->value.data, mval, oi->value.len);
335285

336286
return oi;
337287
}
338288

339289
bool frame_buffer_append_mem_info(FrameBuffer *fbuf, uint64_t vaddr,
340-
qemu_plugin_mem_value *mval, bool is_store) {
341-
OperandInfo *oi = frame_init_mem_operand_info(vaddr, mval, is_store);
290+
const uint8_t *mval, size_t mval_bits,
291+
bool is_store) {
292+
OperandInfo *oi =
293+
frame_init_mem_operand_info(vaddr, mval, mval_bits, is_store);
342294
g_assert(oi);
343295
return append_op_info(fbuf, oi);
344296
}

‎contrib/plugins/bap-tracing/frame_buffer.h

Lines changed: 2 additions & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -41,7 +41,8 @@ bool frame_buffer_new_frame_std(FrameBuffer *buf, unsigned int thread_id,
4141
uint8_t *bytes, size_t bytes_len);
4242

4343
bool frame_buffer_append_mem_info(FrameBuffer *fbuf, uint64_t vaddr,
44-
qemu_plugin_mem_value *mval, bool is_store);
44+
const uint8_t *mval, size_t mval_bits,
45+
bool is_store);
4546

4647
/**
4748
* \brief Appends the given operand info to the open frame.

‎contrib/plugins/bap-tracing/trace_meta.c

Lines changed: 1 addition & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -193,7 +193,7 @@ void write_meta(WLOCKED FILE *file, char **plugin_argv, size_t plugin_argc) {
193193
}
194194

195195
/// Copies src to dst. dst will always be in little endian byte order.
196-
void memcpy_le(uint8_t *dst, uint8_t *src, size_t len, bool big_endian) {
196+
void memcpy_le(uint8_t *dst, const uint8_t *src, size_t len, bool big_endian) {
197197
if (!big_endian) {
198198
memcpy(dst, src, len);
199199
return;

‎contrib/plugins/bap-tracing/trace_meta.h

Lines changed: 1 addition & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -36,7 +36,7 @@
3636
void write_meta(WLOCKED FILE *file, char **plugin_argv, size_t plugin_argc);
3737
char *get_argv_val(char **argv, int argc, const char *key);
3838
void file_exists_exit(const char *file);
39-
void memcpy_le(uint8_t *dst, uint8_t *src, size_t len, bool big_endian);
39+
void memcpy_le(uint8_t *dst, const uint8_t *src, size_t len, bool big_endian);
4040
void swap_to_le(uint8_t *buf, size_t len, bool big_endian);
4141

4242
#endif

‎contrib/plugins/bap-tracing/tracing.c

Lines changed: 74 additions & 4 deletions
Original file line numberDiff line numberDiff line change
@@ -15,10 +15,71 @@
1515

1616
static TraceState state = {0};
1717

18+
static void mval_to_buf(qemu_plugin_mem_value *val, uint8_t *buf) {
19+
size_t mem_val_size = 0;
20+
switch (val->type) {
21+
case QEMU_PLUGIN_MEM_VALUE_U8:
22+
buf[0] = val->data.u8;
23+
mem_val_size = 1;
24+
break;
25+
case QEMU_PLUGIN_MEM_VALUE_U16:
26+
buf[0] = (uint8_t)val->data.u16;
27+
buf[1] = (uint8_t)(val->data.u16 >> 8);
28+
mem_val_size = 2;
29+
break;
30+
case QEMU_PLUGIN_MEM_VALUE_U32:
31+
buf[0] = (uint8_t)val->data.u32;
32+
buf[1] = (uint8_t)(val->data.u32 >> 8);
33+
buf[2] = (uint8_t)(val->data.u32 >> 16);
34+
buf[3] = (uint8_t)(val->data.u32 >> 24);
35+
mem_val_size = 4;
36+
break;
37+
case QEMU_PLUGIN_MEM_VALUE_U64:
38+
for (size_t i = 0; i < 8; ++i) {
39+
buf[i] = (uint8_t)(val->data.u64 >> (i * 8));
40+
}
41+
mem_val_size = 8;
42+
break;
43+
case QEMU_PLUGIN_MEM_VALUE_U128:
44+
for (size_t i = 0; i < 8; ++i) {
45+
buf[i] = (uint8_t)(val->data.u128.low >> (i * 8));
46+
}
47+
for (size_t i = 0; i < 8; ++i) {
48+
buf[i + 8] = (uint8_t)(val->data.u128.high >> (i * 8));
49+
}
50+
mem_val_size = 16;
51+
break;
52+
default:
53+
g_assert(false);
54+
}
55+
swap_to_le(buf, mem_val_size, state.is_big_endian);
56+
}
57+
58+
static size_t mval_type_to_int(enum qemu_plugin_mem_value_type type) {
59+
switch (type) {
60+
case QEMU_PLUGIN_MEM_VALUE_U8:
61+
return 8;
62+
case QEMU_PLUGIN_MEM_VALUE_U16:
63+
return 16;
64+
case QEMU_PLUGIN_MEM_VALUE_U32:
65+
return 32;
66+
case QEMU_PLUGIN_MEM_VALUE_U64:
67+
return 64;
68+
case QEMU_PLUGIN_MEM_VALUE_U128:
69+
return 128;
70+
default:
71+
g_assert(false);
72+
}
73+
return 0;
74+
}
75+
1876
static void add_mem_op(VCPU *vcpu, unsigned int vcpu_index, FrameBuffer *fbuf,
1977
uint64_t vaddr, qemu_plugin_mem_value *mval,
2078
bool is_store) {
21-
if (!frame_buffer_append_mem_info(fbuf, vaddr, mval, is_store)) {
79+
size_t mval_bits = mval_type_to_int(mval->type);
80+
uint8_t *buf = g_malloc(mval_bits / 8);
81+
mval_to_buf(mval, buf);
82+
if (!frame_buffer_append_mem_info(fbuf, vaddr, buf, mval_bits, is_store)) {
2283
qemu_plugin_outs("Failed to append memory info\n");
2384
}
2485
return;
@@ -54,7 +115,7 @@ static void add_post_reg_state(VCPU *vcpu, unsigned int vcpu_index,
54115
&g_array_index(current_regs, qemu_plugin_reg_descriptor, i);
55116
int s = qemu_plugin_read_register(reg->handle, rdata);
56117
assert(s == prev_reg->content->len);
57-
swap_to_le(rdata->data, s, HOST_BIG_ENDIAN);
118+
swap_to_le(rdata->data, s, state.is_big_endian);
58119
if (!memcmp(rdata->data, prev_reg->content->data, s)) {
59120
// No change
60121
// Flush byte array
@@ -83,8 +144,9 @@ static void add_pre_reg_state(VCPU *vcpu, unsigned int vcpu_index,
83144
g_assert(!strcmp(prev_reg->name, reg->name) &&
84145
prev_reg->handle == reg->handle);
85146
memcpy_le(prev_reg->content->data, rdata->data, prev_reg->content->len,
86-
HOST_BIG_ENDIAN);
87-
frame_buffer_append_reg_info(fbuf, reg->name, rdata, s, OperandRead);
147+
state.is_big_endian);
148+
frame_buffer_append_reg_info(fbuf, reg->name, prev_reg->content, s,
149+
OperandRead);
88150
// Flush byte array
89151
g_byte_array_set_size(rdata, 0);
90152
}
@@ -342,6 +404,14 @@ QEMU_PLUGIN_EXPORT int qemu_plugin_install(qemu_plugin_id_t id,
342404
qemu_plugin_outs("Pass it with 'out=<output_file>'.\n\n");
343405
exit(1);
344406
}
407+
char *endianess = get_argv_val(argv, argc, "endianess");
408+
if (!endianess || (strcmp(endianess, "b") && strcmp(endianess, "l"))) {
409+
qemu_plugin_outs("'endianess' argument is missing or is not 'b' or 'l'.\n");
410+
qemu_plugin_outs("This is required until QEMU plugins get a richer API.\n");
411+
qemu_plugin_outs("Pass it with 'endianess=[b/l]'.\n\n");
412+
exit(1);
413+
}
414+
state.is_big_endian = endianess[0] == 'b';
345415

346416
state.target_name = g_strdup(info->target_name);
347417
state.frame_buffer = g_ptr_array_new();

‎contrib/plugins/bap-tracing/tracing.h

Lines changed: 1 addition & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -171,6 +171,7 @@ typedef struct {
171171
GPtrArray /*<const char *>*/ *vcpu_modes; ///< Indexed by vcpu id.
172172

173173
const char *target_name;
174+
bool is_big_endian;
174175
} TraceState;
175176

176177
VCPU *vcpu_new(void);

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