On 16/07/2017 11:29, Dmitry Fleytman wrote:
According to PCI spec. bit 1 of command
register (PCI_COMMAND_MEMORY) controls
a device's response to memory space accesses.
A value of 0 disables the device response.
A value of 1 allows the device to respond
to memory space accesses.
Hi Dmitry,
Current behavior introduced by commit
commit 1c380f9460522f32c8dd2577b2a53d518ec91c6d
Author: Avi Kivity <a...@redhat.com>
Date: Wed Oct 3 17:42:58 2012 +0200
pci: honor PCI_COMMAND_MASTER
is to ignore device memory space accesses unless
bit 2 (PCI_COMMAND_MASTER) is set.
Aforementioned commit introduced regression of
Windows hibernation (S4) functionality support
because on resume Windows kernel sets bits 0 and 1
(PCI_COMMAND_MEMORY | PCI_COMMAND_IO) of boot
device's (piix3-ide in our specific case) command
register and tries to work with the device.
> Since PCI_COMMAND_MASTER bit is not set, device
does not answer and Windows fails to resume from
hibernation.
As far as I am aware "Bus master" is needed for a device
to start PCI transactions, while PCI_COMMAND_MEMORY/IO
controls the device ability to respond to memory/IO accesses,
not to start them.
If "Bus master" is needed for DMA access or MSI, the OS should
explicitly set the PCI_COMMAND_MASTER, right?
As a result following BSOD happens:
BugCheck A0, {10e, a, aa00, 418}
Probably caused by : ntkrnlmp.exe ( nt!PopHiberChecksumHiberFileData+b346 )
Followup: MachineOwner
---------
0: kd> !analyze -v
*******************************************************************************
*
*
* Bugcheck Analysis
*
*
*
*******************************************************************************
INTERNAL_POWER_ERROR (a0)
The power policy manager experienced a fatal error.
Arguments:
Arg1: 000000000000010e, The disk subsystem returned corrupt data while
reading from the
hibernation file.
Arg2: 000000000000000a
Arg3: 000000000000aa00, Incorrect checksum
Arg4: 0000000000000418, Previous disk read's checksum
Does piix3-ide fail to respond to IO/MEM accesses if
PCI_COMMAND_MASTER is not set? Or is it a DMA issue?
Thanks,
Marcel
According to our tests this problem happens at least on
Windows 8/8.1/2012/2012R2/10/2016.
This patch solves https://bugzilla.redhat.com/show_bug.cgi?id=988351
Signed-off-by: Dmitry Fleytman <dmi...@daynix.com>
---
hw/pci/pci.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/hw/pci/pci.c b/hw/pci/pci.c
index 0c6f74a..10af82f 100644
--- a/hw/pci/pci.c
+++ b/hw/pci/pci.c
@@ -480,7 +480,7 @@ static int get_pci_config_device(QEMUFile *f, void *pv,
size_t size,
memory_region_set_enabled(&s->bus_master_enable_region,
pci_get_word(s->config + PCI_COMMAND)
- & PCI_COMMAND_MASTER);
+ & (PCI_COMMAND_MASTER | PCI_COMMAND_MEMORY));
g_free(config);
return 0;
@@ -1356,7 +1356,7 @@ void pci_default_write_config(PCIDevice *d, uint32_t
addr, uint32_t val_in, int
pci_update_irq_disabled(d, was_irq_disabled);
memory_region_set_enabled(&d->bus_master_enable_region,
pci_get_word(d->config + PCI_COMMAND)
- & PCI_COMMAND_MASTER);
+ & (PCI_COMMAND_MASTER | PCI_COMMAND_MEMORY));
}
msi_write_config(d, addr, val_in, l);
