| Message ID | 20250326095224.9918-1-jinpu.wang@ionos.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | [RFC] migration/rdma: Remove qemu_rdma_broken_ipv6_kernel | expand |
On Wed, Mar 26, 2025 at 2:47 PM Michael Galaxy <michael@flatgalaxy.com> wrote: > > Excellent find. Thank you very much for checking on the history. Hopefully my comments were not too hard to read. =) Yeah, it's pretty clear. > > FYI: I've since left Akamai last year and now work at Nvidia. > > Reviewed-by: Michael Galaxy <mrgalaxy@nvidia.com> cool, thx for the review. All the best at your new job. > > On 3/26/25 04:52, Jack Wang wrote: > > I hit following error which testing migration in pure RoCE env: > "-incoming rdma:[::]:8089: RDMA ERROR: You only have RoCE / iWARP devices in your > systems and your management software has specified '[::]', but IPv6 over RoCE / > iWARP is not supported in Linux.#012'." > > In our setup, we use rdma bind on ipv6 on target host, while connect from source > with ipv4, remove the qemu_rdma_broken_ipv6_kernel, migration just work > fine. > > Checking the git history, the function was added since introducing of > rdma migration, which is more than 10 years ago. linux-rdma has > improved support on RoCE/iWARP for ipv6 over past years. There are a few fixes > back in 2016 seems related to the issue, eg: > aeb76df46d11 ("IB/core: Set routable RoCE gid type for ipv4/ipv6 networks") > > other fixes back in 2018, eg: > 052eac6eeb56 RDMA/cma: Update RoCE multicast routines to use net namespace > 8d20a1f0ecd5 RDMA/cma: Fix rdma_cm raw IB path setting for RoCE > 9327c7afdce3 RDMA/cma: Provide a function to set RoCE path record L2 parameters > 5c181bda77f4 RDMA/cma: Set default GID type as RoCE when resolving RoCE route > 3c7f67d1880d IB/cma: Fix default RoCE type setting > be1d325a3358 IB/core: Set RoCEv2 MGID according to spec > 63a5f483af0e IB/cma: Set default gid type to RoCEv2 > > So remove the outdated function and it's usage. > > Cc: Peter Xu <peterx@redhat.com> > Cc: Li Zhijian <lizhijian@fujitsu.com> > Cc: Yu Zhang <yu.zhang@ionos.com> > Cc: qemu-devel@nongnu.org > Cc: linux-rdma@vger.kernel.org > Cc: michael@flatgalaxy.com > Signed-off-by: Jack Wang <jinpu.wang@ionos.com> > --- > migration/rdma.c | 157 ----------------------------------------------- > 1 file changed, 157 deletions(-) > > diff --git a/migration/rdma.c b/migration/rdma.c > index 76fb0349238a..5ce628ddeef0 100644 > --- a/migration/rdma.c > +++ b/migration/rdma.c > @@ -767,149 +767,6 @@ static void qemu_rdma_dump_gid(const char *who, struct rdma_cm_id *id) > trace_qemu_rdma_dump_gid(who, sgid, dgid); > } > > -/* > - * As of now, IPv6 over RoCE / iWARP is not supported by linux. > - * We will try the next addrinfo struct, and fail if there are > - * no other valid addresses to bind against. > - * > - * If user is listening on '[::]', then we will not have a opened a device > - * yet and have no way of verifying if the device is RoCE or not. > - * > - * In this case, the source VM will throw an error for ALL types of > - * connections (both IPv4 and IPv6) if the destination machine does not have > - * a regular infiniband network available for use. > - * > - * The only way to guarantee that an error is thrown for broken kernels is > - * for the management software to choose a *specific* interface at bind time > - * and validate what time of hardware it is. > - * > - * Unfortunately, this puts the user in a fix: > - * > - * If the source VM connects with an IPv4 address without knowing that the > - * destination has bound to '[::]' the migration will unconditionally fail > - * unless the management software is explicitly listening on the IPv4 > - * address while using a RoCE-based device. > - * > - * If the source VM connects with an IPv6 address, then we're OK because we can > - * throw an error on the source (and similarly on the destination). > - * > - * But in mixed environments, this will be broken for a while until it is fixed > - * inside linux. > - * > - * We do provide a *tiny* bit of help in this function: We can list all of the > - * devices in the system and check to see if all the devices are RoCE or > - * Infiniband. > - * > - * If we detect that we have a *pure* RoCE environment, then we can safely > - * thrown an error even if the management software has specified '[::]' as the > - * bind address. > - * > - * However, if there is are multiple hetergeneous devices, then we cannot make > - * this assumption and the user just has to be sure they know what they are > - * doing. > - * > - * Patches are being reviewed on linux-rdma. > - */ > -static int qemu_rdma_broken_ipv6_kernel(struct ibv_context *verbs, Error **errp) > -{ > - /* This bug only exists in linux, to our knowledge. */ > -#ifdef CONFIG_LINUX > - struct ibv_port_attr port_attr; > - > - /* > - * Verbs are only NULL if management has bound to '[::]'. > - * > - * Let's iterate through all the devices and see if there any pure IB > - * devices (non-ethernet). > - * > - * If not, then we can safely proceed with the migration. > - * Otherwise, there are no guarantees until the bug is fixed in linux. > - */ > - if (!verbs) { > - int num_devices; > - struct ibv_device **dev_list = ibv_get_device_list(&num_devices); > - bool roce_found = false; > - bool ib_found = false; > - > - for (int x = 0; x < num_devices; x++) { > - verbs = ibv_open_device(dev_list[x]); > - /* > - * ibv_open_device() is not documented to set errno. If > - * it does, it's somebody else's doc bug. If it doesn't, > - * the use of errno below is wrong. > - * TODO Find out whether ibv_open_device() sets errno. > - */ > - if (!verbs) { > - if (errno == EPERM) { > - continue; > - } else { > - error_setg_errno(errp, errno, > - "could not open RDMA device context"); > - return -1; > - } > - } > - > - if (ibv_query_port(verbs, 1, &port_attr)) { > - ibv_close_device(verbs); > - error_setg(errp, > - "RDMA ERROR: Could not query initial IB port"); > - return -1; > - } > - > - if (port_attr.link_layer == IBV_LINK_LAYER_INFINIBAND) { > - ib_found = true; > - } else if (port_attr.link_layer == IBV_LINK_LAYER_ETHERNET) { > - roce_found = true; > - } > - > - ibv_close_device(verbs); > - > - } > - > - if (roce_found) { > - if (ib_found) { > - warn_report("migrations may fail:" > - " IPv6 over RoCE / iWARP in linux" > - " is broken. But since you appear to have a" > - " mixed RoCE / IB environment, be sure to only" > - " migrate over the IB fabric until the kernel " > - " fixes the bug."); > - } else { > - error_setg(errp, "RDMA ERROR: " > - "You only have RoCE / iWARP devices in your systems" > - " and your management software has specified '[::]'" > - ", but IPv6 over RoCE / iWARP is not supported in Linux."); > - return -1; > - } > - } > - > - return 0; > - } > - > - /* > - * If we have a verbs context, that means that some other than '[::]' was > - * used by the management software for binding. In which case we can > - * actually warn the user about a potentially broken kernel. > - */ > - > - /* IB ports start with 1, not 0 */ > - if (ibv_query_port(verbs, 1, &port_attr)) { > - error_setg(errp, "RDMA ERROR: Could not query initial IB port"); > - return -1; > - } > - > - if (port_attr.link_layer == IBV_LINK_LAYER_ETHERNET) { > - error_setg(errp, "RDMA ERROR: " > - "Linux kernel's RoCE / iWARP does not support IPv6 " > - "(but patches on linux-rdma in progress)"); > - return -1; > - } > - > -#endif > - > - return 0; > -} > - > /* > * Figure out which RDMA device corresponds to the requested IP hostname > * Also create the initial connection manager identifiers for opening > @@ -964,13 +821,6 @@ static int qemu_rdma_resolve_host(RDMAContext *rdma, Error **errp) > ret = rdma_resolve_addr(rdma->cm_id, NULL, e->ai_dst_addr, > RDMA_RESOLVE_TIMEOUT_MS); > if (ret >= 0) { > - if (e->ai_family == AF_INET6) { > - ret = qemu_rdma_broken_ipv6_kernel(rdma->cm_id->verbs, > - local_errp); > - if (ret < 0) { > - continue; > - } > - } > error_free(err); > goto route; > } > @@ -2672,13 +2522,6 @@ static int qemu_rdma_dest_init(RDMAContext *rdma, Error **errp) > if (ret < 0) { > continue; > } > - if (e->ai_family == AF_INET6) { > - ret = qemu_rdma_broken_ipv6_kernel(listen_id->verbs, > - local_errp); > - if (ret < 0) { > - continue; > - } > - } > error_free(err); > break; > }
Please fix this compiling error.
cc -m64 -mcx16 -Ilibcommon.a.p -Isubprojects/libvduse -I../subprojects/libvduse -I/usr/include/p11-kit-1 -I/usr/include/pixman-1 -I/usr/include/libpng16 -I/usr/include/spice-server -I/usr/include/spice-1 -I/usr/include/libusb-1.0 -I/usr/include/glib-2.0 -I/usr/lib/x86_64-linux-gnu/glib-2.0/include -I/usr/include/libmount -I/usr/include/blkid -I/usr/include/gio-unix-2.0 -I/usr/include/gtk-3.0 -I/usr/include/pango-1.0 -I/usr/include/harfbuzz -I/usr/include/freetype2 -I/usr/include/fribidi -I/usr/include/uuid -I/usr/include/cairo -I/usr/include/gdk-pixbuf-2.0 -I/usr/include/x86_64-linux-gnu -I/usr/include/atk-1.0 -I/usr/include/at-spi2-atk/2.0 -I/usr/include/dbus-1.0 -I/usr/lib/x86_64-linux-gnu/dbus-1.0/include -I/usr/include/at-spi-2.0 -I/usr/include/cacard -I/usr/include/nss -I/usr/include/nspr -I/usr/include/PCSC -fdiagnostics-color=auto -Wall -Winvalid-pch -Werror -std=gnu11 -O2 -g -fstack-protector-strong -gsplit-dwarf -Wempty-body -Wendif-labels -Wexpansion-to-defined -Wformat-security -Wformat-y2k -Wignored-qualifiers -Wimplicit-fallthrough=2 -Winit-self -Wmissing-format-attribute -Wmissing-prototypes -Wnested-externs -Wold-style-declaration -Wold-style-definition -Wredundant-decls -Wshadow=local -Wstrict-prototypes -Wtype-limits -Wundef -Wvla -Wwrite-strings -Wno-missing-include-dirs -Wno-psabi -Wno-shift-negative-value -isystem /home/lizj/workspace/qemu/qemu/linux-headers -isystem linux-headers -iquote . -iquote /home/lizj/workspace/qemu/qemu -iquote /home/lizj/workspace/qemu/qemu/include -iquote /home/lizj/workspace/qemu/qemu/host/include/x86_64 -iquote /home/lizj/workspace/qemu/qemu/host/include/generic -iquote /home/lizj/workspace/qemu/qemu/tcg/i386 -pthread -mcx16 -msse2 -D_GNU_SOURCE -D_FILE_OFFSET_BITS=64 -D_LARGEFILE_SOURCE -fno-strict-aliasing -fno-common -fwrapv -fzero-call-used-regs=used-gpr -fPIE -D_DEFAULT_SOURCE -D_XOPEN_SOURCE=600 -DNCURSES_WIDECHAR=1 -DSTRUCT_IOVEC_DEFINED -MD -MQ libcommon.a.p/migration_rdma.c.o -MF libcommon.a.p/migration_rdma.c.o.d -o libcommon.a.p/migration_rdma.c.o -c ../migration/rdma.c
../migration/rdma.c: In function ‘qemu_rdma_resolve_host’:
../migration/rdma.c:815:17: error: unused variable ‘local_errp’ [-Werror=unused-variable]
815 | Error **local_errp = err ? NULL : &err;
| ^~~~~~~~~~
../migration/rdma.c: In function ‘qemu_rdma_dest_init’:
../migration/rdma.c:2504:17: error: unused variable ‘local_errp’ [-Werror=unused-variable]
2504 | Error **local_errp = err ? NULL : &err;
| ^~~~~~~~~~
cc1: all warnings being treated as errors
[17/19] Compiling C object qemu-img.p/qemu-img.c.o
After this fixing, feel free to add
Tested-by: Li zhijian <lizhijian@fujitsu.com>
On 26/03/2025 17:52, Jack Wang wrote:
> I hit following error which testing migration in pure RoCE env:
> "-incoming rdma:[::]:8089: RDMA ERROR: You only have RoCE / iWARP devices in your
> systems and your management software has specified '[::]', but IPv6 over RoCE /
> iWARP is not supported in Linux.#012'."
>
> In our setup, we use rdma bind on ipv6 on target host, while connect from source
> with ipv4, remove the qemu_rdma_broken_ipv6_kernel, migration just work
> fine.
>
> Checking the git history, the function was added since introducing of
> rdma migration, which is more than 10 years ago. linux-rdma has
> improved support on RoCE/iWARP for ipv6 over past years. There are a few fixes
> back in 2016 seems related to the issue, eg:
> aeb76df46d11 ("IB/core: Set routable RoCE gid type for ipv4/ipv6 networks")
>
> other fixes back in 2018, eg:
> 052eac6eeb56 RDMA/cma: Update RoCE multicast routines to use net namespace
> 8d20a1f0ecd5 RDMA/cma: Fix rdma_cm raw IB path setting for RoCE
> 9327c7afdce3 RDMA/cma: Provide a function to set RoCE path record L2 parameters
> 5c181bda77f4 RDMA/cma: Set default GID type as RoCE when resolving RoCE route
> 3c7f67d1880d IB/cma: Fix default RoCE type setting
> be1d325a3358 IB/core: Set RoCEv2 MGID according to spec
> 63a5f483af0e IB/cma: Set default gid type to RoCEv2
>
> So remove the outdated function and it's usage.
>
> Cc: Peter Xu <peterx@redhat.com>
> Cc: Li Zhijian <lizhijian@fujitsu.com>
> Cc: Yu Zhang <yu.zhang@ionos.com>
> Cc: qemu-devel@nongnu.org
> Cc: linux-rdma@vger.kernel.org
> Cc: michael@flatgalaxy.com
> Signed-off-by: Jack Wang <jinpu.wang@ionos.com>
> ---
> migration/rdma.c | 157 -----------------------------------------------
> 1 file changed, 157 deletions(-)
>
> diff --git a/migration/rdma.c b/migration/rdma.c
> index 76fb0349238a..5ce628ddeef0 100644
> --- a/migration/rdma.c
> +++ b/migration/rdma.c
> @@ -767,149 +767,6 @@ static void qemu_rdma_dump_gid(const char *who, struct rdma_cm_id *id)
> trace_qemu_rdma_dump_gid(who, sgid, dgid);
> }
>
> -/*
> - * As of now, IPv6 over RoCE / iWARP is not supported by linux.
> - * We will try the next addrinfo struct, and fail if there are
> - * no other valid addresses to bind against.
> - *
> - * If user is listening on '[::]', then we will not have a opened a device
> - * yet and have no way of verifying if the device is RoCE or not.
> - *
> - * In this case, the source VM will throw an error for ALL types of
> - * connections (both IPv4 and IPv6) if the destination machine does not have
> - * a regular infiniband network available for use.
> - *
> - * The only way to guarantee that an error is thrown for broken kernels is
> - * for the management software to choose a *specific* interface at bind time
> - * and validate what time of hardware it is.
> - *
> - * Unfortunately, this puts the user in a fix:
> - *
> - * If the source VM connects with an IPv4 address without knowing that the
> - * destination has bound to '[::]' the migration will unconditionally fail
> - * unless the management software is explicitly listening on the IPv4
> - * address while using a RoCE-based device.
> - *
> - * If the source VM connects with an IPv6 address, then we're OK because we can
> - * throw an error on the source (and similarly on the destination).
> - *
> - * But in mixed environments, this will be broken for a while until it is fixed
> - * inside linux.
> - *
> - * We do provide a *tiny* bit of help in this function: We can list all of the
> - * devices in the system and check to see if all the devices are RoCE or
> - * Infiniband.
> - *
> - * If we detect that we have a *pure* RoCE environment, then we can safely
> - * thrown an error even if the management software has specified '[::]' as the
> - * bind address.
> - *
> - * However, if there is are multiple hetergeneous devices, then we cannot make
> - * this assumption and the user just has to be sure they know what they are
> - * doing.
> - *
> - * Patches are being reviewed on linux-rdma.
> - */
> -static int qemu_rdma_broken_ipv6_kernel(struct ibv_context *verbs, Error **errp)
> -{
> - /* This bug only exists in linux, to our knowledge. */
> -#ifdef CONFIG_LINUX
> - struct ibv_port_attr port_attr;
> -
> - /*
> - * Verbs are only NULL if management has bound to '[::]'.
> - *
> - * Let's iterate through all the devices and see if there any pure IB
> - * devices (non-ethernet).
> - *
> - * If not, then we can safely proceed with the migration.
> - * Otherwise, there are no guarantees until the bug is fixed in linux.
> - */
> - if (!verbs) {
> - int num_devices;
> - struct ibv_device **dev_list = ibv_get_device_list(&num_devices);
> - bool roce_found = false;
> - bool ib_found = false;
> -
> - for (int x = 0; x < num_devices; x++) {
> - verbs = ibv_open_device(dev_list[x]);
> - /*
> - * ibv_open_device() is not documented to set errno. If
> - * it does, it's somebody else's doc bug. If it doesn't,
> - * the use of errno below is wrong.
> - * TODO Find out whether ibv_open_device() sets errno.
> - */
> - if (!verbs) {
> - if (errno == EPERM) {
> - continue;
> - } else {
> - error_setg_errno(errp, errno,
> - "could not open RDMA device context");
> - return -1;
> - }
> - }
> -
> - if (ibv_query_port(verbs, 1, &port_attr)) {
> - ibv_close_device(verbs);
> - error_setg(errp,
> - "RDMA ERROR: Could not query initial IB port");
> - return -1;
> - }
> -
> - if (port_attr.link_layer == IBV_LINK_LAYER_INFINIBAND) {
> - ib_found = true;
> - } else if (port_attr.link_layer == IBV_LINK_LAYER_ETHERNET) {
> - roce_found = true;
> - }
> -
> - ibv_close_device(verbs);
> -
> - }
> -
> - if (roce_found) {
> - if (ib_found) {
> - warn_report("migrations may fail:"
> - " IPv6 over RoCE / iWARP in linux"
> - " is broken. But since you appear to have a"
> - " mixed RoCE / IB environment, be sure to only"
> - " migrate over the IB fabric until the kernel "
> - " fixes the bug.");
> - } else {
> - error_setg(errp, "RDMA ERROR: "
> - "You only have RoCE / iWARP devices in your systems"
> - " and your management software has specified '[::]'"
> - ", but IPv6 over RoCE / iWARP is not supported in Linux.");
> - return -1;
> - }
> - }
> -
> - return 0;
> - }
> -
> - /*
> - * If we have a verbs context, that means that some other than '[::]' was
> - * used by the management software for binding. In which case we can
> - * actually warn the user about a potentially broken kernel.
> - */
> -
> - /* IB ports start with 1, not 0 */
> - if (ibv_query_port(verbs, 1, &port_attr)) {
> - error_setg(errp, "RDMA ERROR: Could not query initial IB port");
> - return -1;
> - }
> -
> - if (port_attr.link_layer == IBV_LINK_LAYER_ETHERNET) {
> - error_setg(errp, "RDMA ERROR: "
> - "Linux kernel's RoCE / iWARP does not support IPv6 "
> - "(but patches on linux-rdma in progress)");
> - return -1;
> - }
> -
> -#endif
> -
> - return 0;
> -}
> -
> /*
> * Figure out which RDMA device corresponds to the requested IP hostname
> * Also create the initial connection manager identifiers for opening
> @@ -964,13 +821,6 @@ static int qemu_rdma_resolve_host(RDMAContext *rdma, Error **errp)
> ret = rdma_resolve_addr(rdma->cm_id, NULL, e->ai_dst_addr,
> RDMA_RESOLVE_TIMEOUT_MS);
> if (ret >= 0) {
> - if (e->ai_family == AF_INET6) {
> - ret = qemu_rdma_broken_ipv6_kernel(rdma->cm_id->verbs,
> - local_errp);
> - if (ret < 0) {
> - continue;
> - }
> - }
> error_free(err);
> goto route;
> }
> @@ -2672,13 +2522,6 @@ static int qemu_rdma_dest_init(RDMAContext *rdma, Error **errp)
> if (ret < 0) {
> continue;
> }
> - if (e->ai_family == AF_INET6) {
> - ret = qemu_rdma_broken_ipv6_kernel(listen_id->verbs,
> - local_errp);
> - if (ret < 0) {
> - continue;
> - }
> - }
> error_free(err);
> break;
> }
Hi Zhijian, On Thu, Mar 27, 2025 at 2:18 AM Zhijian Li (Fujitsu) <lizhijian@fujitsu.com> wrote: > > > Please fix this compiling error. > > > cc -m64 -mcx16 -Ilibcommon.a.p -Isubprojects/libvduse -I../subprojects/libvduse -I/usr/include/p11-kit-1 -I/usr/include/pixman-1 -I/usr/include/libpng16 -I/usr/include/spice-server -I/usr/include/spice-1 -I/usr/include/libusb-1.0 -I/usr/include/glib-2.0 -I/usr/lib/x86_64-linux-gnu/glib-2.0/include -I/usr/include/libmount -I/usr/include/blkid -I/usr/include/gio-unix-2.0 -I/usr/include/gtk-3.0 -I/usr/include/pango-1.0 -I/usr/include/harfbuzz -I/usr/include/freetype2 -I/usr/include/fribidi -I/usr/include/uuid -I/usr/include/cairo -I/usr/include/gdk-pixbuf-2.0 -I/usr/include/x86_64-linux-gnu -I/usr/include/atk-1.0 -I/usr/include/at-spi2-atk/2.0 -I/usr/include/dbus-1.0 -I/usr/lib/x86_64-linux-gnu/dbus-1.0/include -I/usr/include/at-spi-2.0 -I/usr/include/cacard -I/usr/include/nss -I/usr/include/nspr -I/usr/include/PCSC -fdiagnostics-color=auto -Wall -Winvalid-pch -Werror -std=gnu11 -O2 -g -fstack-protector-strong -gsplit-dwarf -Wempty-body -Wendif-labels -Wexpansion-to-defined -Wformat-security -Wformat-y2k -Wignored-qualifiers -Wimplicit-fallthrough=2 -Winit-self -Wmissing-format-attribute -Wmissing-prototypes -Wnested-externs -Wold-style-declaration -Wold-style-definition -Wredundant-decls -Wshadow=local -Wstrict-prototypes -Wtype-limits -Wundef -Wvla -Wwrite-strings -Wno-missing-include-dirs -Wno-psabi -Wno-shift-negative-value -isystem /home/lizj/workspace/qemu/qemu/linux-headers -isystem linux-headers -iquote . -iquote /home/lizj/workspace/qemu/qemu -iquote /home/lizj/workspace/qemu/qemu/include -iquote /home/lizj/workspace/qemu/qemu/host/include/x86_64 -iquote /home/lizj/workspace/qemu/qemu/host/include/generic -iquote /home/lizj/workspace/qemu/qemu/tcg/i386 -pthread -mcx16 -msse2 -D_GNU_SOURCE -D_FILE_OFFSET_BITS=64 -D_LARGEFILE_SOURCE -fno-strict-aliasing -fno-common -fwrapv -fzero-call-used-regs=used-gpr -fPIE -D_DEFAULT_SOURCE -D_XOPEN_SOURCE=600 -DNCURSES_WIDECHAR=1 -DSTRUCT_IOVEC_DEFINED -MD -MQ libcommon.a.p/migration_rdma.c.o -MF libcommon.a.p/migration_rdma.c.o.d -o libcommon.a.p/migration_rdma.c.o -c ../migration/rdma.c > ../migration/rdma.c: In function ‘qemu_rdma_resolve_host’: > ../migration/rdma.c:815:17: error: unused variable ‘local_errp’ [-Werror=unused-variable] > 815 | Error **local_errp = err ? NULL : &err; > | ^~~~~~~~~~ > ../migration/rdma.c: In function ‘qemu_rdma_dest_init’: > ../migration/rdma.c:2504:17: error: unused variable ‘local_errp’ [-Werror=unused-variable] > 2504 | Error **local_errp = err ? NULL : &err; > | ^~~~~~~~~~ > cc1: all warnings being treated as errors > [17/19] Compiling C object qemu-img.p/qemu-img.c.o > > > After this fixing, feel free to add > > Tested-by: Li zhijian <lizhijian@fujitsu.com> Thx for checking, will fix them. > > > On 26/03/2025 17:52, Jack Wang wrote: > > I hit following error which testing migration in pure RoCE env: > > "-incoming rdma:[::]:8089: RDMA ERROR: You only have RoCE / iWARP devices in your > > systems and your management software has specified '[::]', but IPv6 over RoCE / > > iWARP is not supported in Linux.#012'." > > > > In our setup, we use rdma bind on ipv6 on target host, while connect from source > > with ipv4, remove the qemu_rdma_broken_ipv6_kernel, migration just work > > fine. > > > > Checking the git history, the function was added since introducing of > > rdma migration, which is more than 10 years ago. linux-rdma has > > improved support on RoCE/iWARP for ipv6 over past years. There are a few fixes > > back in 2016 seems related to the issue, eg: > > aeb76df46d11 ("IB/core: Set routable RoCE gid type for ipv4/ipv6 networks") > > > > other fixes back in 2018, eg: > > 052eac6eeb56 RDMA/cma: Update RoCE multicast routines to use net namespace > > 8d20a1f0ecd5 RDMA/cma: Fix rdma_cm raw IB path setting for RoCE > > 9327c7afdce3 RDMA/cma: Provide a function to set RoCE path record L2 parameters > > 5c181bda77f4 RDMA/cma: Set default GID type as RoCE when resolving RoCE route > > 3c7f67d1880d IB/cma: Fix default RoCE type setting > > be1d325a3358 IB/core: Set RoCEv2 MGID according to spec > > 63a5f483af0e IB/cma: Set default gid type to RoCEv2 > > > > So remove the outdated function and it's usage. > > > > Cc: Peter Xu <peterx@redhat.com> > > Cc: Li Zhijian <lizhijian@fujitsu.com> > > Cc: Yu Zhang <yu.zhang@ionos.com> > > Cc: qemu-devel@nongnu.org > > Cc: linux-rdma@vger.kernel.org > > Cc: michael@flatgalaxy.com > > Signed-off-by: Jack Wang <jinpu.wang@ionos.com> > > --- > > migration/rdma.c | 157 ----------------------------------------------- > > 1 file changed, 157 deletions(-) > > > > diff --git a/migration/rdma.c b/migration/rdma.c > > index 76fb0349238a..5ce628ddeef0 100644 > > --- a/migration/rdma.c > > +++ b/migration/rdma.c > > @@ -767,149 +767,6 @@ static void qemu_rdma_dump_gid(const char *who, struct rdma_cm_id *id) > > trace_qemu_rdma_dump_gid(who, sgid, dgid); > > } > > > > -/* > > - * As of now, IPv6 over RoCE / iWARP is not supported by linux. > > - * We will try the next addrinfo struct, and fail if there are > > - * no other valid addresses to bind against. > > - * > > - * If user is listening on '[::]', then we will not have a opened a device > > - * yet and have no way of verifying if the device is RoCE or not. > > - * > > - * In this case, the source VM will throw an error for ALL types of > > - * connections (both IPv4 and IPv6) if the destination machine does not have > > - * a regular infiniband network available for use. > > - * > > - * The only way to guarantee that an error is thrown for broken kernels is > > - * for the management software to choose a *specific* interface at bind time > > - * and validate what time of hardware it is. > > - * > > - * Unfortunately, this puts the user in a fix: > > - * > > - * If the source VM connects with an IPv4 address without knowing that the > > - * destination has bound to '[::]' the migration will unconditionally fail > > - * unless the management software is explicitly listening on the IPv4 > > - * address while using a RoCE-based device. > > - * > > - * If the source VM connects with an IPv6 address, then we're OK because we can > > - * throw an error on the source (and similarly on the destination). > > - * > > - * But in mixed environments, this will be broken for a while until it is fixed > > - * inside linux. > > - * > > - * We do provide a *tiny* bit of help in this function: We can list all of the > > - * devices in the system and check to see if all the devices are RoCE or > > - * Infiniband. > > - * > > - * If we detect that we have a *pure* RoCE environment, then we can safely > > - * thrown an error even if the management software has specified '[::]' as the > > - * bind address. > > - * > > - * However, if there is are multiple hetergeneous devices, then we cannot make > > - * this assumption and the user just has to be sure they know what they are > > - * doing. > > - * > > - * Patches are being reviewed on linux-rdma. > > - */ > > -static int qemu_rdma_broken_ipv6_kernel(struct ibv_context *verbs, Error **errp) > > -{ > > - /* This bug only exists in linux, to our knowledge. */ > > -#ifdef CONFIG_LINUX > > - struct ibv_port_attr port_attr; > > - > > - /* > > - * Verbs are only NULL if management has bound to '[::]'. > > - * > > - * Let's iterate through all the devices and see if there any pure IB > > - * devices (non-ethernet). > > - * > > - * If not, then we can safely proceed with the migration. > > - * Otherwise, there are no guarantees until the bug is fixed in linux. > > - */ > > - if (!verbs) { > > - int num_devices; > > - struct ibv_device **dev_list = ibv_get_device_list(&num_devices); > > - bool roce_found = false; > > - bool ib_found = false; > > - > > - for (int x = 0; x < num_devices; x++) { > > - verbs = ibv_open_device(dev_list[x]); > > - /* > > - * ibv_open_device() is not documented to set errno. If > > - * it does, it's somebody else's doc bug. If it doesn't, > > - * the use of errno below is wrong. > > - * TODO Find out whether ibv_open_device() sets errno. > > - */ > > - if (!verbs) { > > - if (errno == EPERM) { > > - continue; > > - } else { > > - error_setg_errno(errp, errno, > > - "could not open RDMA device context"); > > - return -1; > > - } > > - } > > - > > - if (ibv_query_port(verbs, 1, &port_attr)) { > > - ibv_close_device(verbs); > > - error_setg(errp, > > - "RDMA ERROR: Could not query initial IB port"); > > - return -1; > > - } > > - > > - if (port_attr.link_layer == IBV_LINK_LAYER_INFINIBAND) { > > - ib_found = true; > > - } else if (port_attr.link_layer == IBV_LINK_LAYER_ETHERNET) { > > - roce_found = true; > > - } > > - > > - ibv_close_device(verbs); > > - > > - } > > - > > - if (roce_found) { > > - if (ib_found) { > > - warn_report("migrations may fail:" > > - " IPv6 over RoCE / iWARP in linux" > > - " is broken. But since you appear to have a" > > - " mixed RoCE / IB environment, be sure to only" > > - " migrate over the IB fabric until the kernel " > > - " fixes the bug."); > > - } else { > > - error_setg(errp, "RDMA ERROR: " > > - "You only have RoCE / iWARP devices in your systems" > > - " and your management software has specified '[::]'" > > - ", but IPv6 over RoCE / iWARP is not supported in Linux."); > > - return -1; > > - } > > - } > > - > > - return 0; > > - } > > - > > - /* > > - * If we have a verbs context, that means that some other than '[::]' was > > - * used by the management software for binding. In which case we can > > - * actually warn the user about a potentially broken kernel. > > - */ > > - > > - /* IB ports start with 1, not 0 */ > > - if (ibv_query_port(verbs, 1, &port_attr)) { > > - error_setg(errp, "RDMA ERROR: Could not query initial IB port"); > > - return -1; > > - } > > - > > - if (port_attr.link_layer == IBV_LINK_LAYER_ETHERNET) { > > - error_setg(errp, "RDMA ERROR: " > > - "Linux kernel's RoCE / iWARP does not support IPv6 " > > - "(but patches on linux-rdma in progress)"); > > - return -1; > > - } > > - > > -#endif > > - > > - return 0; > > -} > > - > > /* > > * Figure out which RDMA device corresponds to the requested IP hostname > > * Also create the initial connection manager identifiers for opening > > @@ -964,13 +821,6 @@ static int qemu_rdma_resolve_host(RDMAContext *rdma, Error **errp) > > ret = rdma_resolve_addr(rdma->cm_id, NULL, e->ai_dst_addr, > > RDMA_RESOLVE_TIMEOUT_MS); > > if (ret >= 0) { > > - if (e->ai_family == AF_INET6) { > > - ret = qemu_rdma_broken_ipv6_kernel(rdma->cm_id->verbs, > > - local_errp); > > - if (ret < 0) { > > - continue; > > - } > > - } > > error_free(err); > > goto route; > > } > > @@ -2672,13 +2522,6 @@ static int qemu_rdma_dest_init(RDMAContext *rdma, Error **errp) > > if (ret < 0) { > > continue; > > } > > - if (e->ai_family == AF_INET6) { > > - ret = qemu_rdma_broken_ipv6_kernel(listen_id->verbs, > > - local_errp); > > - if (ret < 0) { > > - continue; > > - } > > - } > > error_free(err); > > break; > > }
diff --git a/migration/rdma.c b/migration/rdma.c index 76fb0349238a..5ce628ddeef0 100644 --- a/migration/rdma.c +++ b/migration/rdma.c @@ -767,149 +767,6 @@ static void qemu_rdma_dump_gid(const char *who, struct rdma_cm_id *id) trace_qemu_rdma_dump_gid(who, sgid, dgid); } -/* - * As of now, IPv6 over RoCE / iWARP is not supported by linux. - * We will try the next addrinfo struct, and fail if there are - * no other valid addresses to bind against. - * - * If user is listening on '[::]', then we will not have a opened a device - * yet and have no way of verifying if the device is RoCE or not. - * - * In this case, the source VM will throw an error for ALL types of - * connections (both IPv4 and IPv6) if the destination machine does not have - * a regular infiniband network available for use. - * - * The only way to guarantee that an error is thrown for broken kernels is - * for the management software to choose a *specific* interface at bind time - * and validate what time of hardware it is. - * - * Unfortunately, this puts the user in a fix: - * - * If the source VM connects with an IPv4 address without knowing that the - * destination has bound to '[::]' the migration will unconditionally fail - * unless the management software is explicitly listening on the IPv4 - * address while using a RoCE-based device. - * - * If the source VM connects with an IPv6 address, then we're OK because we can - * throw an error on the source (and similarly on the destination). - * - * But in mixed environments, this will be broken for a while until it is fixed - * inside linux. - * - * We do provide a *tiny* bit of help in this function: We can list all of the - * devices in the system and check to see if all the devices are RoCE or - * Infiniband. - * - * If we detect that we have a *pure* RoCE environment, then we can safely - * thrown an error even if the management software has specified '[::]' as the - * bind address. - * - * However, if there is are multiple hetergeneous devices, then we cannot make - * this assumption and the user just has to be sure they know what they are - * doing. - * - * Patches are being reviewed on linux-rdma. - */ -static int qemu_rdma_broken_ipv6_kernel(struct ibv_context *verbs, Error **errp) -{ - /* This bug only exists in linux, to our knowledge. */ -#ifdef CONFIG_LINUX - struct ibv_port_attr port_attr; - - /* - * Verbs are only NULL if management has bound to '[::]'. - * - * Let's iterate through all the devices and see if there any pure IB - * devices (non-ethernet). - * - * If not, then we can safely proceed with the migration. - * Otherwise, there are no guarantees until the bug is fixed in linux. - */ - if (!verbs) { - int num_devices; - struct ibv_device **dev_list = ibv_get_device_list(&num_devices); - bool roce_found = false; - bool ib_found = false; - - for (int x = 0; x < num_devices; x++) { - verbs = ibv_open_device(dev_list[x]); - /* - * ibv_open_device() is not documented to set errno. If - * it does, it's somebody else's doc bug. If it doesn't, - * the use of errno below is wrong. - * TODO Find out whether ibv_open_device() sets errno. - */ - if (!verbs) { - if (errno == EPERM) { - continue; - } else { - error_setg_errno(errp, errno, - "could not open RDMA device context"); - return -1; - } - } - - if (ibv_query_port(verbs, 1, &port_attr)) { - ibv_close_device(verbs); - error_setg(errp, - "RDMA ERROR: Could not query initial IB port"); - return -1; - } - - if (port_attr.link_layer == IBV_LINK_LAYER_INFINIBAND) { - ib_found = true; - } else if (port_attr.link_layer == IBV_LINK_LAYER_ETHERNET) { - roce_found = true; - } - - ibv_close_device(verbs); - - } - - if (roce_found) { - if (ib_found) { - warn_report("migrations may fail:" - " IPv6 over RoCE / iWARP in linux" - " is broken. But since you appear to have a" - " mixed RoCE / IB environment, be sure to only" - " migrate over the IB fabric until the kernel " - " fixes the bug."); - } else { - error_setg(errp, "RDMA ERROR: " - "You only have RoCE / iWARP devices in your systems" - " and your management software has specified '[::]'" - ", but IPv6 over RoCE / iWARP is not supported in Linux."); - return -1; - } - } - - return 0; - } - - /* - * If we have a verbs context, that means that some other than '[::]' was - * used by the management software for binding. In which case we can - * actually warn the user about a potentially broken kernel. - */ - - /* IB ports start with 1, not 0 */ - if (ibv_query_port(verbs, 1, &port_attr)) { - error_setg(errp, "RDMA ERROR: Could not query initial IB port"); - return -1; - } - - if (port_attr.link_layer == IBV_LINK_LAYER_ETHERNET) { - error_setg(errp, "RDMA ERROR: " - "Linux kernel's RoCE / iWARP does not support IPv6 " - "(but patches on linux-rdma in progress)"); - return -1; - } - -#endif - - return 0; -} - /* * Figure out which RDMA device corresponds to the requested IP hostname * Also create the initial connection manager identifiers for opening @@ -964,13 +821,6 @@ static int qemu_rdma_resolve_host(RDMAContext *rdma, Error **errp) ret = rdma_resolve_addr(rdma->cm_id, NULL, e->ai_dst_addr, RDMA_RESOLVE_TIMEOUT_MS); if (ret >= 0) { - if (e->ai_family == AF_INET6) { - ret = qemu_rdma_broken_ipv6_kernel(rdma->cm_id->verbs, - local_errp); - if (ret < 0) { - continue; - } - } error_free(err); goto route; } @@ -2672,13 +2522,6 @@ static int qemu_rdma_dest_init(RDMAContext *rdma, Error **errp) if (ret < 0) { continue; } - if (e->ai_family == AF_INET6) { - ret = qemu_rdma_broken_ipv6_kernel(listen_id->verbs, - local_errp); - if (ret < 0) { - continue; - } - } error_free(err); break; }
I hit following error which testing migration in pure RoCE env: "-incoming rdma:[::]:8089: RDMA ERROR: You only have RoCE / iWARP devices in your systems and your management software has specified '[::]', but IPv6 over RoCE / iWARP is not supported in Linux.#012'." In our setup, we use rdma bind on ipv6 on target host, while connect from source with ipv4, remove the qemu_rdma_broken_ipv6_kernel, migration just work fine. Checking the git history, the function was added since introducing of rdma migration, which is more than 10 years ago. linux-rdma has improved support on RoCE/iWARP for ipv6 over past years. There are a few fixes back in 2016 seems related to the issue, eg: aeb76df46d11 ("IB/core: Set routable RoCE gid type for ipv4/ipv6 networks") other fixes back in 2018, eg: 052eac6eeb56 RDMA/cma: Update RoCE multicast routines to use net namespace 8d20a1f0ecd5 RDMA/cma: Fix rdma_cm raw IB path setting for RoCE 9327c7afdce3 RDMA/cma: Provide a function to set RoCE path record L2 parameters 5c181bda77f4 RDMA/cma: Set default GID type as RoCE when resolving RoCE route 3c7f67d1880d IB/cma: Fix default RoCE type setting be1d325a3358 IB/core: Set RoCEv2 MGID according to spec 63a5f483af0e IB/cma: Set default gid type to RoCEv2 So remove the outdated function and it's usage. Cc: Peter Xu <peterx@redhat.com> Cc: Li Zhijian <lizhijian@fujitsu.com> Cc: Yu Zhang <yu.zhang@ionos.com> Cc: qemu-devel@nongnu.org Cc: linux-rdma@vger.kernel.org Cc: michael@flatgalaxy.com Signed-off-by: Jack Wang <jinpu.wang@ionos.com> --- migration/rdma.c | 157 ----------------------------------------------- 1 file changed, 157 deletions(-)