| Message ID | 1435866681-18468-5-git-send-email-konrad.wilk@oracle.com |
|---|---|
| State | New |
| Headers | show |
On Thu, 2 Jul 2015, Konrad Rzeszutek Wilk wrote: > Otherwise we get: > > xen_pt_config_reg_init: Offset 0x0004 mismatch! Emulated=0x0000, host=0x2300017, syncing to 0x2300014. > xen_pt_config_reg_init: Error: Offset 0x0004:0x2300014 expands past register size(2)! > > which is not surprising. We read the value as an 32-bit (from host), > then operate it as a 16-bit - and the remainder is left unchanged. > > We end up writting the value as 16-bit (so 0014) to dev.config ^ writing > (as we use proper xen_set_host_[byte,word,long] so we don't spill > to other registers) but in XenPTReg->data it is as 32-bit (0x2300014)! > > It is harmless as the read/write functions end up using an size mask > and never modify the bits past 16-bit (reg->size is 2). > > This patch fixes the warnings by reading the value using the > proper size. > > Note that the check for size is still left in-case the developer > sets bits past the reg->size in the ->init routines. > > Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> > --- > hw/xen/xen_pt_config_init.c | 7 ++++++- > 1 file changed, 6 insertions(+), 1 deletion(-) > > diff --git a/hw/xen/xen_pt_config_init.c b/hw/xen/xen_pt_config_init.c > index 09309ba..e597993 100644 > --- a/hw/xen/xen_pt_config_init.c > +++ b/hw/xen/xen_pt_config_init.c > @@ -1876,7 +1876,12 @@ static int xen_pt_config_reg_init(XenPCIPassthroughState *s, > offset = reg_grp->base_offset + reg->offset; > size_mask = 0xFFFFFFFF >> ((4 - reg->size) << 3); > > - rc = xen_host_pci_get_long(&s->real_device, offset, &val); > + switch (reg->size) { > + case 1: rc = xen_host_pci_get_byte(&s->real_device, offset, (uint8_t *)&val);break; > + case 2: rc = xen_host_pci_get_word(&s->real_device, offset, (uint16_t *)&val);break; > + case 4: rc = xen_host_pci_get_long(&s->real_device, offset, &val);break; > + default: assert(1); > + } > if (rc) { > /* Serious issues when we cannot read the host values! */ > g_free(reg_entry); Please merge this patch with patch #2/10. It is best to place the break statements on new lines, to follow QEMU's code style.
diff --git a/hw/xen/xen_pt_config_init.c b/hw/xen/xen_pt_config_init.c index 09309ba..e597993 100644 --- a/hw/xen/xen_pt_config_init.c +++ b/hw/xen/xen_pt_config_init.c @@ -1876,7 +1876,12 @@ static int xen_pt_config_reg_init(XenPCIPassthroughState *s, offset = reg_grp->base_offset + reg->offset; size_mask = 0xFFFFFFFF >> ((4 - reg->size) << 3); - rc = xen_host_pci_get_long(&s->real_device, offset, &val); + switch (reg->size) { + case 1: rc = xen_host_pci_get_byte(&s->real_device, offset, (uint8_t *)&val);break; + case 2: rc = xen_host_pci_get_word(&s->real_device, offset, (uint16_t *)&val);break; + case 4: rc = xen_host_pci_get_long(&s->real_device, offset, &val);break; + default: assert(1); + } if (rc) { /* Serious issues when we cannot read the host values! */ g_free(reg_entry);
Otherwise we get: xen_pt_config_reg_init: Offset 0x0004 mismatch! Emulated=0x0000, host=0x2300017, syncing to 0x2300014. xen_pt_config_reg_init: Error: Offset 0x0004:0x2300014 expands past register size(2)! which is not surprising. We read the value as an 32-bit (from host), then operate it as a 16-bit - and the remainder is left unchanged. We end up writting the value as 16-bit (so 0014) to dev.config (as we use proper xen_set_host_[byte,word,long] so we don't spill to other registers) but in XenPTReg->data it is as 32-bit (0x2300014)! It is harmless as the read/write functions end up using an size mask and never modify the bits past 16-bit (reg->size is 2). This patch fixes the warnings by reading the value using the proper size. Note that the check for size is still left in-case the developer sets bits past the reg->size in the ->init routines. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> --- hw/xen/xen_pt_config_init.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-)