Re: [PATCH v2 00/20] vfio: Add migration pre-copy support and device dirty tracking

["Cédric Le Goater" <clg@redhat.com>]

On 2/26/23 18:00, Avihai Horon wrote:
> 
> On 24/02/2023 21:26, Joao Martins wrote:
>> External email: Use caution opening links or attachments
>>
>>
>> On 23/02/2023 14:56, Avihai Horon wrote:
>>> On 22/02/2023 22:55, Alex Williamson wrote:
>>>> There are various errors running this through the CI on gitlab.
>>>>
>>>> This one seems bogus but needs to be resolved regardless:
>>>>
>>>> https://gitlab.com/alex.williamson/qemu/-/jobs/3817940731
>>>> FAILED: libqemu-aarch64-softmmu.fa.p/hw_vfio_common.c.o
>>>> 2786s390x-linux-gnu-gcc -m64 -Ilibqemu-aarch64-softmmu.fa.p -I. -I..
>>>> -Itarget/arm -I../target/arm -Iqapi -Itrace -Iui -Iui/shader
>>>> -I/usr/include/pixman-1 -I/usr/include/capstone -I/usr/include/glib-2.0
>>>> -I/usr/lib/s390x-linux-gnu/glib-2.0/include -fdiagnostics-color=auto -Wall
>>>> -Winvalid-pch -Werror -std=gnu11 -O2 -g -isystem
>>>> /builds/alex.williamson/qemu/linux-headers -isystem linux-headers -iquote .
>>>> -iquote /builds/alex.williamson/qemu -iquote
>>>> /builds/alex.williamson/qemu/include -iquote
>>>> /builds/alex.williamson/qemu/tcg/s390x -pthread -U_FORTIFY_SOURCE
>>>> -D_FORTIFY_SOURCE=2 -D_GNU_SOURCE -D_FILE_OFFSET_BITS=64 -D_LARGEFILE_SOURCE
>>>> -fno-strict-aliasing -fno-common -fwrapv -Wundef -Wwrite-strings
>>>> -Wmissing-prototypes -Wstrict-prototypes -Wredundant-decls
>>>> -Wold-style-declaration -Wold-style-definition -Wtype-limits -Wformat-security
>>>> -Wformat-y2k -Winit-self -Wignored-qualifiers -Wempty-body -Wnested-externs
>>>> -Wendif-labels -Wexpansion-to-defined -Wimplicit-fallthrough=2
>>>> -Wmissing-format-attribute -Wno-missing-include-dirs -Wno-shift-negative-value
>>>> -Wno-psabi -fstack-protector-strong -fPIE -isystem../linux-headers
>>>> -isystemlinux-headers -DNEED_CPU_H
>>>> '-DCONFIG_TARGET="aarch64-softmmu-config-target.h"'
>>>> '-DCONFIG_DEVICES="aarch64-softmmu-config-devices.h"' -MD -MQ
>>>> libqemu-aarch64-softmmu.fa.p/hw_vfio_common.c.o -MF
>>>> libqemu-aarch64-softmmu.fa.p/hw_vfio_common.c.o.d -o
>>>> libqemu-aarch64-softmmu.fa.p/hw_vfio_common.c.o -c ../hw/vfio/common.c
>>>> 2787../hw/vfio/common.c: In function ‘vfio_listener_log_global_start’:
>>>> 2788../hw/vfio/common.c:1772:8: error: ‘ret’ may be used uninitialized in this
>>>> function [-Werror=maybe-uninitialized]
>>>> 2789 1772 |     if (ret) {
>>>> 2790      |        ^
>>>>
>>>> 32-bit builds have some actual errors though:
>>>>
>>>> https://gitlab.com/alex.williamson/qemu/-/jobs/3817940719
>>>> FAILED: libqemu-aarch64-softmmu.fa.p/hw_vfio_common.c.o
>>>> 2601cc -m32 -Ilibqemu-aarch64-softmmu.fa.p -I. -I.. -Itarget/arm
>>>> -I../target/arm -Iqapi -Itrace -Iui -Iui/shader -I/usr/include/pixman-1
>>>> -I/usr/include/glib-2.0 -I/usr/lib/glib-2.0/include -I/usr/include/sysprof-4
>>>> -fdiagnostics-color=auto -Wall -Winvalid-pch -Werror -std=gnu11 -O2 -g
>>>> -isystem /builds/alex.williamson/qemu/linux-headers -isystem linux-headers
>>>> -iquote . -iquote /builds/alex.williamson/qemu -iquote
>>>> /builds/alex.williamson/qemu/include -iquote
>>>> /builds/alex.williamson/qemu/tcg/i386 -pthread -U_FORTIFY_SOURCE
>>>> -D_FORTIFY_SOURCE=2 -D_GNU_SOURCE -D_FILE_OFFSET_BITS=64 -D_LARGEFILE_SOURCE
>>>> -fno-strict-aliasing -fno-common -fwrapv -Wundef -Wwrite-strings
>>>> -Wmissing-prototypes -Wstrict-prototypes -Wredundant-decls
>>>> -Wold-style-declaration -Wold-style-definition -Wtype-limits -Wformat-security
>>>> -Wformat-y2k -Winit-self -Wignored-qualifiers -Wempty-body -Wnested-externs
>>>> -Wendif-labels -Wexpansion-to-defined -Wimplicit-fallthrough=2
>>>> -Wmissing-format-attribute -Wno-missing-include-dirs -Wno-shift-negative-value
>>>> -Wno-psabi -fstack-protector-strong -fPIE -isystem../linux-headers
>>>> -isystemlinux-headers -DNEED_CPU_H
>>>> '-DCONFIG_TARGET="aarch64-softmmu-config-target.h"'
>>>> '-DCONFIG_DEVICES="aarch64-softmmu-config-devices.h"' -MD -MQ
>>>> libqemu-aarch64-softmmu.fa.p/hw_vfio_common.c.o -MF
>>>> libqemu-aarch64-softmmu.fa.p/hw_vfio_common.c.o.d -o
>>>> libqemu-aarch64-softmmu.fa.p/hw_vfio_common.c.o -c ../hw/vfio/common.c
>>>> 2602../hw/vfio/common.c: In function
>>>> 'vfio_device_feature_dma_logging_start_create':
>>>> 2603../hw/vfio/common.c:1572:27: error: cast from pointer to integer of
>>>> different size [-Werror=pointer-to-int-cast]
>>>> 2604 1572 |         control->ranges = (uint64_t)ranges;
>>>> 2605      |                           ^
>>>> 2606../hw/vfio/common.c:1596:23: error: cast from pointer to integer of
>>>> different size [-Werror=pointer-to-int-cast]
>>>> 2607 1596 |     control->ranges = (uint64_t)ranges;
>>>> 2608      |                       ^
>>>> 2609../hw/vfio/common.c: In function
>>>> 'vfio_device_feature_dma_logging_start_destroy':
>>>> 2610../hw/vfio/common.c:1620:9: error: cast to pointer from integer of
>>>> different size [-Werror=int-to-pointer-cast]
>>>> 2611 1620 |         (struct vfio_device_feature_dma_logging_range
>>>> *)control->ranges;
>>>> 2612      |         ^
>>>> 2613../hw/vfio/common.c: In function 'vfio_device_dma_logging_report':
>>>> 2614../hw/vfio/common.c:1810:22: error: cast from pointer to integer of
>>>> different size [-Werror=pointer-to-int-cast]
>>>> 2615 1810 |     report->bitmap = (uint64_t)bitmap;
>>>> 2616      |                      ^
>>> Sure, I will fix these errors.
>> Just a thought: should the pre-copy series be moved towards the end of this
>> series, given that it's more of an improvement of downtime than a must-have like
>> dirty tracking?
> 
> Given recent discussion, maybe it would be better to split this series and go one step at a time:
> Start with basic support for device dirty tracking (without vIOMMU support), then add pre-copy and then add vIOMMU support to device dirty tracking.

and add the fixes first in the series. They could be merged quickly.

Thanks,

C.