The patch
apci: fix PXB behaviour if used with unsupported BIOS
uses the following condition to see if a "PXB mem/IO chunk" has *not* been
configured by the BIOS:
(!range_base || range_base > range_limit)
When this condition evaluates to true, said patch *omits* the
corresponding entry from the _CRS.
Later on the patch checks for the opposite condition (with the intent of
*adding* entries to the _CRS if the "PXB mem/IO chunks" *have* been
configured). Unfortunately, the condition was negated incorrectly: only
the first ! operator was removed, which led to the nonsensical expression
(range_base || range_base > range_limit)
leading to bogus entries in the _CRS, and causing BSOD in Windows Server
2012 R2 when it runs on OVMF.
The correct negative of the condition seen at the top is
(range_base && range_base <= range_limit)
Fix the expressions.
Cc: Marcel Apfelbaum <mar...@redhat.com>
Cc: Michael S. Tsirkin <m...@redhat.com>
Signed-off-by: Laszlo Ersek <ler...@redhat.com>
---
hw/i386/acpi-build.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)
diff --git a/hw/i386/acpi-build.c b/hw/i386/acpi-build.c
index 52c2591..b71e942 100644
--- a/hw/i386/acpi-build.c
+++ b/hw/i386/acpi-build.c
@@ -833,7 +833,7 @@ static Aml *build_crs(PCIHostState *host,
* Work-around for old bioses
* that do not support multiple root buses
*/
- if (range_base || range_base > range_limit) {
+ if (range_base && range_base <= range_limit) {
aml_append(crs,
aml_word_io(AML_MIN_FIXED, AML_MAX_FIXED,
AML_POS_DECODE, AML_ENTIRE_RANGE,
@@ -854,7 +854,7 @@ static Aml *build_crs(PCIHostState *host,
* Work-around for old bioses
* that do not support multiple root buses
*/
- if (range_base || range_base > range_limit) {
+ if (range_base && range_base <= range_limit) {
aml_append(crs,
aml_dword_memory(AML_POS_DECODE, AML_MIN_FIXED,
AML_MAX_FIXED, AML_NON_CACHEABLE,
@@ -865,7 +865,7 @@ static Aml *build_crs(PCIHostState *host,
0,
range_limit - range_base + 1));
crs_range_insert(mem_ranges, range_base, range_limit);
- }
+ }
range_base =
pci_bridge_get_base(dev, PCI_BASE_ADDRESS_MEM_PREFETCH);
@@ -876,7 +876,7 @@ static Aml *build_crs(PCIHostState *host,
* Work-around for old bioses
* that do not support multiple root buses
*/
- if (range_base || range_base > range_limit) {
+ if (range_base && range_base <= range_limit) {
aml_append(crs,
aml_dword_memory(AML_POS_DECODE, AML_MIN_FIXED,
AML_MAX_FIXED, AML_NON_CACHEABLE,
--
1.8.3.1
