mirrors/qemu
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

aml-build: don't modify child

Browse Source 
this code:
    aml_append(foo, bar);

might, non-intuitively, modify bar, which means that e.g. the following
might not DTRT:

    c = ....;
    aml_append(a, c);
    aml_append(b, c);

to fix, simply allocate an intermediate array,
and always modify that.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
This commit is contained in:
Michael S. Tsirkin 2015-03-07 20:47:51 +01:00
parent 8437f7be3b
commit 7d433b0d85
1 changed files with 10 additions and 6 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

16
hw/acpi/aml-build.c
View File

@ -335,26 +335,29 @@ static void build_buffer(GArray *array, uint8_t op)
void aml_append(Aml *parent_ctx, Aml *child)
{
GArray *buf = build_alloc_array();
build_append_array(buf, child->buf);
switch (child->block_flags) {
case AML_OPCODE:
build_append_byte(parent_ctx->buf, child->op);
break;
case AML_EXT_PACKAGE:
build_extop_package(child->buf, child->op);
build_extop_package(buf, child->op);
break;
case AML_PACKAGE:
build_package(child->buf, child->op);
build_package(buf, child->op);
break;
case AML_RES_TEMPLATE:
build_append_byte(child->buf, 0x79); /* EndTag */
build_append_byte(buf, 0x79); /* EndTag */
/*
* checksum operations are treated as succeeded if checksum
* field is zero. [ACPI Spec 1.0b, 6.4.2.8 End Tag]
*/
build_append_byte(child->buf, 0);
build_append_byte(buf, 0);
/* fall through, to pack resources in buffer */
case AML_BUFFER:
build_buffer(child->buf, child->op);
build_buffer(buf, child->op);
break;
case AML_NO_OPCODE:
break;
@ -362,7 +365,8 @@ void aml_append(Aml *parent_ctx, Aml *child)
assert(0);
break;
}
build_append_array(parent_ctx->buf, child->buf);
build_append_array(parent_ctx->buf, buf);
build_free_array(buf);
}
/* ACPI 1.0b: 16.2.5.1 Namespace Modifier Objects Encoding: DefScope */