On 11/14/2017 06:47 PM, Marc-André Lureau wrote:
Hi
On Tue, Nov 14, 2017 at 10:52 PM, Stefan Berger
<stef...@linux.vnet.ibm.com> wrote:
Rather than returning ~0, return 0 for every register in case of
failure mode. The '0' is better to indicate that there's no device
there.
For most registers, 0 makes more sense. However, I wonder if we
shouldn't just fail to start qemu in this case...
Not convincing me this is 2.11 material either. Does this fix a specific bug?
Yes, SeaBIOS detects the ~0 when it probes and thinks there's a device
there. It then hangs trying to set flags and read registers to be able
to use the device.
Stefan
Signed-off-by: Stefan Berger <stef...@linux.vnet.ibm.com>
---
hw/tpm/tpm_tis.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/hw/tpm/tpm_tis.c b/hw/tpm/tpm_tis.c
index fec2fc6..42d647d 100644
--- a/hw/tpm/tpm_tis.c
+++ b/hw/tpm/tpm_tis.c
@@ -545,7 +545,7 @@ static uint64_t tpm_tis_mmio_read(void *opaque, hwaddr addr,
uint8_t v;
if (tpm_backend_had_startup_error(s->be_driver)) {
- return val;
+ return 0;
}
switch (offset) {
--
2.5.5
