(no subject)

[Dev Audsin]

virtio-fs with DAX is currently not compatible with NIC Pass through.
When a SR-IOV VF attaches to a qemu process, vfio will try to pin the entire DAX Window but it is empty when the guest boots and will fail.
A method to make VFIO and DAX to work together is to make vfio skip DAX cache.
Currently DAX cache need to be set to 0, for the SR-IOV VF to be attached to Kata containers.
Enabling both SR-IOV VF and DAX work together will potentially improve performance for workloads which are I/O and network intensive

[PATCH] skip virtio fs cache section to enable NIC passthrough

[Dev Audsin]

Signed-off-by: Dev Audsin <dev.devaqemu@gmail.com>
---
 hw/vfio/common.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/hw/vfio/common.c b/hw/vfio/common.c
index 6ff1daa763..3af70238bd 100644
--- a/hw/vfio/common.c
+++ b/hw/vfio/common.c
@@ -541,7 +541,8 @@ static int vfio_host_win_del(VFIOContainer *container, hwaddr min_iova,
 
 static bool vfio_listener_skipped_section(MemoryRegionSection *section)
 {
-    return (!memory_region_is_ram(section->mr) &&
+    return (!strcmp(memory_region_name(section->mr), "virtio-fs-cache")) ||
+    	   (!memory_region_is_ram(section->mr) &&
             !memory_region_is_iommu(section->mr)) ||
            /*
             * Sizing an enabled 64-bit BAR can cause spurious mappings to
-- 
2.25.1

Re: [PATCH] skip virtio fs cache section to enable NIC passthrough

[no-reply]

Patchew URL: https://patchew.org/QEMU/20210426200553.145976-2-dev.devaqemu@gmail.com/



Hi,

This series seems to have some coding style problems. See output below for
more information:

Type: series
Message-id: 20210426200553.145976-2-dev.devaqemu@gmail.com
Subject: [PATCH] skip virtio fs cache section to enable NIC passthrough

=== TEST SCRIPT BEGIN ===
#!/bin/bash
git rev-parse base > /dev/null || exit 0
git config --local diff.renamelimit 0
git config --local diff.renames True
git config --local diff.algorithm histogram
./scripts/checkpatch.pl --mailback base..
=== TEST SCRIPT END ===

Updating 3c8cf5a9c21ff8782164d1def7f44bd888713384
From https://github.com/patchew-project/qemu
 * [new tag]         patchew/20210426200553.145976-2-dev.devaqemu@gmail.com -> patchew/20210426200553.145976-2-dev.devaqemu@gmail.com
Switched to a new branch 'test'
120a1b0 skip virtio fs cache section to enable NIC passthrough

=== OUTPUT BEGIN ===
ERROR: code indent should never use tabs
#23: FILE: hw/vfio/common.c:540:
+    ^I   (!memory_region_is_ram(section->mr) &&$

total: 1 errors, 0 warnings, 9 lines checked

Commit 120a1b0ec9de (skip virtio fs cache section to enable NIC passthrough) has style problems, please review.  If any of these errors
are false positives report them to the maintainer, see
CHECKPATCH in MAINTAINERS.
=== OUTPUT END ===

Test command exited with code: 1


The full log is available at
http://patchew.org/logs/20210426200553.145976-2-dev.devaqemu@gmail.com/testing.checkpatch/?type=message.
---
Email generated automatically by Patchew [https://patchew.org/].
Please send your feedback to patchew-devel@redhat.com