mirrors/flatcar-scripts
1
0
Fork 0
mirror of https://github.com/flatcar/scripts.git synced 2025-08-16 09:26:58 +02:00
Code Issues Packages Projects Releases Wiki Activity

sys-kernel/coreos-sources: backport kernel patches that fix memory coherence on Hyper-V

Browse Source 
This is v3 of the patchset from here:
https://lore.kernel.org/lkml/1648138492-2191-1-git-send-email-mikelley@microsoft.com/T/#u

There was a slight merge conflict because hv_map_memory/hv_unmap_memory don't
exist in 5.15.
This commit is contained in:
Jeremi Piotrowski 2022-03-24 10:15:08 +00:00
parent 9847794b4f
commit e498f55aaf
3 changed files with 176 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
sdk_container/src/third_party/coreos-overlay/sys-kernel/coreos-sources/coreos-sources-5.15.32.ebuild vendored
View File

@ -37,4 +37,6 @@ UNIPATCH_LIST="
${PATCH_DIR}/z0003-PCI-hv-Make-the-code-arch-neutral-by-adding-arch-spe.patch \
${PATCH_DIR}/z0004-PCI-hv-Add-arm64-Hyper-V-vPCI-support.patch \
${PATCH_DIR}/z0005-Revert-PCI-MSI-Mask-MSI-X-vectors-only-on-success.patch \
${PATCH_DIR}/z0006-Drivers-hv-vmbus-Propagate-VMbus-coherence-to-each-V.patch \
${PATCH_DIR}/z0007-PCI-hv-Propagate-coherence-from-VMbus-device-to-PCI-.patch \
"

126
sdk_container/src/third_party/coreos-overlay/sys-kernel/coreos-sources/files/5.15/z0006-Drivers-hv-vmbus-Propagate-VMbus-coherence-to-each-V.patch vendored Normal file
View File

@ -0,0 +1,126 @@
From b1b77cc3614b1f39a270d203c77d79834e9e91f3 Mon Sep 17 00:00:00 2001
From: Michael Kelley <mikelley@microsoft.com>
Date: Thu, 24 Mar 2022 09:14:51 -0700
Subject: [PATCH 1/2] Drivers: hv: vmbus: Propagate VMbus coherence to each
VMbus device
VMbus synthetic devices are not represented in the ACPI DSDT -- only
the top level VMbus device is represented. As a result, on ARM64
coherence information in the _CCA method is not specified for
synthetic devices, so they default to not hardware coherent.
Drivers for some of these synthetic devices have been recently
updated to use the standard DMA APIs, and they are incurring extra
overhead of unneeded software coherence management.
Fix this by propagating coherence information from the VMbus node
in ACPI to the individual synthetic devices. There's no effect on
x86/x64 where devices are always hardware coherent.
Signed-off-by: Michael Kelley <mikelley@microsoft.com>
Acked-by: Robin Murphy <robin.murphy@arm.com>
---
drivers/hv/hv_common.c | 11 +++++++++++
drivers/hv/vmbus_drv.c | 31 +++++++++++++++++++++++++++++++
include/asm-generic/mshyperv.h | 1 +
3 files changed, 43 insertions(+)
diff --git a/drivers/hv/hv_common.c b/drivers/hv/hv_common.c
index c0d9048a4112..196cedd5f37c 100644
--- a/drivers/hv/hv_common.c
+++ b/drivers/hv/hv_common.c
@@ -20,6 +20,7 @@
#include <linux/panic_notifier.h>
#include <linux/ptrace.h>
#include <linux/slab.h>
+#include <linux/dma-map-ops.h>
#include <asm/hyperv-tlfs.h>
#include <asm/mshyperv.h>
@@ -216,6 +217,16 @@ bool hv_query_ext_cap(u64 cap_query)
}
EXPORT_SYMBOL_GPL(hv_query_ext_cap);
+void hv_setup_dma_ops(struct device *dev, bool coherent)
+{
+ /*
+ * Hyper-V does not offer a vIOMMU in the guest
+ * VM, so pass 0/NULL for the IOMMU settings
+ */
+ arch_setup_dma_ops(dev, 0, 0, NULL, coherent);
+}
+EXPORT_SYMBOL_GPL(hv_setup_dma_ops);
+
bool hv_is_hibernation_supported(void)
{
return !hv_root_partition && acpi_sleep_state_supported(ACPI_STATE_S4);
diff --git a/drivers/hv/vmbus_drv.c b/drivers/hv/vmbus_drv.c
index 44bd0b6ff505..fdbd5531405e 100644
--- a/drivers/hv/vmbus_drv.c
+++ b/drivers/hv/vmbus_drv.c
@@ -919,6 +919,21 @@ static int vmbus_probe(struct device *child_device)
return ret;
}
+/*
+ * vmbus_dma_configure -- Configure DMA coherence for VMbus device
+ */
+static int vmbus_dma_configure(struct device *child_device)
+{
+ /*
+ * On ARM64, propagate the DMA coherence setting from the top level
+ * VMbus ACPI device to the child VMbus device being added here.
+ * On x86/x64 coherence is assumed and these calls have no effect.
+ */
+ hv_setup_dma_ops(child_device,
+ device_get_dma_attr(&hv_acpi_dev->dev) == DEV_DMA_COHERENT);
+ return 0;
+}
+
/*
* vmbus_remove - Remove a vmbus device
*/
@@ -1039,6 +1054,7 @@ static struct bus_type hv_bus = {
.remove = vmbus_remove,
.probe = vmbus_probe,
.uevent = vmbus_uevent,
+ .dma_configure = vmbus_dma_configure,
.dev_groups = vmbus_dev_groups,
.drv_groups = vmbus_drv_groups,
.bus_groups = vmbus_bus_groups,
@@ -2424,6 +2440,21 @@ static int vmbus_acpi_add(struct acpi_device *device)
hv_acpi_dev = device;
+ /*
+ * Older versions of Hyper-V for ARM64 fail to include the _CCA
+ * method on the top level VMbus device in the DSDT. But devices
+ * are hardware coherent in all current Hyper-V use cases, so fix
+ * up the ACPI device to behave as if _CCA is present and indicates
+ * hardware coherence.
+ */
+ ACPI_COMPANION_SET(&device->dev, device);
+ if (IS_ENABLED(CONFIG_ACPI_CCA_REQUIRED) &&
+ device_get_dma_attr(&device->dev) == DEV_DMA_NOT_SUPPORTED) {
+ pr_info("No ACPI _CCA found; assuming coherent device I/O\n");
+ device->flags.cca_seen = true;
+ device->flags.coherent_dma = true;
+ }
+
result = acpi_walk_resources(device->handle, METHOD_NAME__CRS,
vmbus_walk_resources, NULL);
diff --git a/include/asm-generic/mshyperv.h b/include/asm-generic/mshyperv.h
index d3eae6cdbacb..807f1b524af2 100644
--- a/include/asm-generic/mshyperv.h
+++ b/include/asm-generic/mshyperv.h
@@ -256,6 +256,7 @@ enum hv_isolation_type hv_get_isolation_type(void);
bool hv_is_isolation_supported(void);
void hyperv_cleanup(void);
bool hv_query_ext_cap(u64 cap_query);
+void hv_setup_dma_ops(struct device *dev, bool coherent);
#else /* CONFIG_HYPERV */
static inline bool hv_is_hyperv_initialized(void) { return false; }
static inline bool hv_is_hibernation_supported(void) { return false; }
--
2.32.0

48
sdk_container/src/third_party/coreos-overlay/sys-kernel/coreos-sources/files/5.15/z0007-PCI-hv-Propagate-coherence-from-VMbus-device-to-PCI-.patch vendored Normal file
View File

@ -0,0 +1,48 @@
From 9b38850d8ff2bbc6df27d394c825f92d846a6dd9 Mon Sep 17 00:00:00 2001
From: Michael Kelley <mikelley@microsoft.com>
Date: Thu, 24 Mar 2022 09:14:52 -0700
Subject: [PATCH 2/2] PCI: hv: Propagate coherence from VMbus device to PCI
device
PCI pass-thru devices in a Hyper-V VM are represented as a VMBus
device and as a PCI device. The coherence of the VMbus device is
set based on the VMbus node in ACPI, but the PCI device has no
ACPI node and defaults to not hardware coherent. This results
in extra software coherence management overhead on ARM64 when
devices are hardware coherent.
Fix this by setting up the PCI host bus so that normal
PCI mechanisms will propagate the coherence of the VMbus
device to the PCI device. There's no effect on x86/x64 where
devices are always hardware coherent.
Signed-off-by: Michael Kelley <mikelley@microsoft.com>
Acked-by: Boqun Feng <boqun.feng@gmail.com>
Acked-by: Robin Murphy <robin.murphy@arm.com>
---
drivers/pci/controller/pci-hyperv.c | 9 +++++++++
1 file changed, 9 insertions(+)
diff --git a/drivers/pci/controller/pci-hyperv.c b/drivers/pci/controller/pci-hyperv.c
index ddbbdadc8490..95806cb1e4d8 100644
--- a/drivers/pci/controller/pci-hyperv.c
+++ b/drivers/pci/controller/pci-hyperv.c
@@ -3404,6 +3404,15 @@ static int hv_pci_probe(struct hv_device *hdev,
hbus->bridge->domain_nr = dom;
#ifdef CONFIG_X86
hbus->sysdata.domain = dom;
+#elif defined(CONFIG_ARM64)
+ /*
+ * Set the PCI bus parent to be the corresponding VMbus
+ * device. Then the VMbus device will be assigned as the
+ * ACPI companion in pcibios_root_bridge_prepare() and
+ * pci_dma_configure() will propagate device coherence
+ * information to devices created on the bus.
+ */
+ hbus->sysdata.parent = hdev->device.parent;
#endif
hbus->hdev = hdev;
--
2.32.0