Re: [PATCH net-next v1 01/21] devlink: Notify users when objects are accessible

Eric Dumazet
2021-09-28T02:49:26Z

On 9/25/21 4:22 AM, Leon Romanovsky wrote:
> From: Leon Romanovsky <leonro@nvidia.com>
>
> The devlink core code notified users about add/remove objects without
> relation if this object can be accessible or not. In this patch we unify
> such user visible notifications in one place.
>
> Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
> ---
> net/core/devlink.c | 107 +++++++++++++++++++++++++++++++++++++++------
> 1 file changed, 93 insertions(+), 14 deletions(-)
>
> diff --git a/net/core/devlink.c b/net/core/devlink.c
> index 3ea33c689790..06edb2f1d21e 100644
> --- a/net/core/devlink.c
> +++ b/net/core/devlink.c
> @@ -742,6 +742,7 @@ static void devlink_notify(struct devlink *devlink, enum devlink_command cmd)
> int err;
>
> WARN_ON(cmd != DEVLINK_CMD_NEW && cmd != DEVLINK_CMD_DEL);
> + WARN_ON(!xa_get_mark(&devlinks, devlink->index, DEVLINK_REGISTERED));
>
> msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
> if (!msg)
> @@ -1040,11 +1041,15 @@ static int devlink_nl_port_fill(struct sk_buff *msg,
> static void devlink_port_notify(struct devlink_port *devlink_port,
> enum devlink_command cmd)
> {
> + struct devlink *devlink = devlink_port->devlink;
> struct sk_buff *msg;
> int err;
>
> WARN_ON(cmd != DEVLINK_CMD_PORT_NEW && cmd != DEVLINK_CMD_PORT_DEL);
>
> + if (!xa_get_mark(&devlinks, devlink->index, DEVLINK_REGISTERED))
> + return;
> +
> msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
> if (!msg)
> return;
> @@ -1055,18 +1060,19 @@ static void devlink_port_notify(struct devlink_port *devlink_port,
> return;
> }
>
> - genlmsg_multicast_netns(&devlink_nl_family,
> - devlink_net(devlink_port->devlink), msg, 0,
> - DEVLINK_MCGRP_CONFIG, GFP_KERNEL);
> + genlmsg_multicast_netns(&devlink_nl_family, devlink_net(devlink), msg,
> + 0, DEVLINK_MCGRP_CONFIG, GFP_KERNEL);
> }
>
> static void devlink_rate_notify(struct devlink_rate *devlink_rate,
> enum devlink_command cmd)
> {
> + struct devlink *devlink = devlink_rate->devlink;
> struct sk_buff *msg;
> int err;
>
> WARN_ON(cmd != DEVLINK_CMD_RATE_NEW && cmd != DEVLINK_CMD_RATE_DEL);
> + WARN_ON(!xa_get_mark(&devlinks, devlink->index, DEVLINK_REGISTERED));

FYI, this new warning was triggered by syzbot :

WARNING: CPU: 1 PID: 6540 at net/core/devlink.c:5158 devlink_nl_region_notify+0x184/0x1e0 net/core/devlink.c:5158
Modules linked in:
CPU: 1 PID: 6540 Comm: syz-executor.0 Not tainted 5.15.0-rc2-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:devlink_nl_region_notify+0x184/0x1e0 net/core/devlink.c:5158
Code: 38 41 b8 c0 0c 00 00 31 d2 48 89 ee 4c 89 e7 e8 72 1a 26 00 48 83 c4 08 5b 5d 41 5c 41 5d 41 5e e9 01 bd 41 fa e8 fc bc 41 fa <0f> 0b e9 f7 fe ff ff e8 f0 bc 41 fa 0f 0b eb da 4c 89 e7 e8 c4 18
RSP: 0018:ffffc90002d6f658 EFLAGS: 00010293
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: ffff88801f08d580 RSI: ffffffff87344e94 RDI: 0000000000000003
RBP: ffff88801ee42100 R08: 0000000000000000 R09: 0000000000000000
R10: ffffffff87344d8a R11: 0000000000000000 R12: ffff88801c1dc000
R13: 0000000000000000 R14: 000000000000002c R15: ffff88801c1dc070
FS: 0000555555e8e400(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055dd7c590310 CR3: 0000000069a09000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
devlink_region_create+0x39f/0x4c0 net/core/devlink.c:10327
nsim_dev_dummy_region_init drivers/net/netdevsim/dev.c:481 [inline]
nsim_dev_probe+0x5f6/0x1150 drivers/net/netdevsim/dev.c:1479
call_driver_probe drivers/base/dd.c:517 [inline]
really_probe+0x245/0xcc0 drivers/base/dd.c:596
__driver_probe_device+0x338/0x4d0 drivers/base/dd.c:751
driver_probe_device+0x4c/0x1a0 drivers/base/dd.c:781
__device_attach_driver+0x20b/0x2f0 drivers/base/dd.c:898
bus_for_each_drv+0x15f/0x1e0 drivers/base/bus.c:427
__device_attach+0x228/0x4a0 drivers/base/dd.c:969
bus_probe_device+0x1e4/0x290 drivers/base/bus.c:487
device_add+0xc35/0x21b0 drivers/base/core.c:3359
nsim_bus_dev_new drivers/net/netdevsim/bus.c:435 [inline]
new_device_store+0x48b/0x770 drivers/net/netdevsim/bus.c:302
bus_attr_store+0x72/0xa0 drivers/base/bus.c:122
sysfs_kf_write+0x110/0x160 fs/sysfs/file.c:139
kernfs_fop_write_iter+0x342/0x500 fs/kernfs/file.c:296
call_write_iter include/linux/fs.h:2163 [inline]
new_sync_write+0x429/0x660 fs/read_write.c:507
vfs_write+0x7cf/0xae0 fs/read_write.c:594
ksys_write+0x12d/0x250 fs/read_write.c:647
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7f328409d3ef
Code: 89 54 24 18 48 89 74 24 10 89 7c 24 08 e8 99 fd ff ff 48 8b 54 24 18 48 8b 74 24 10 41 89 c0 8b 7c 24 08 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 31 44 89 c7 48 89 44 24 08 e8 cc fd ff ff 48
RSP: 002b:00007ffdc6851140 EFLAGS: 00000293 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007f328409d3ef
RDX: 0000000000000003 RSI: 00007ffdc6851190 RDI: 0000000000000004
RBP: 0000000000000004 R08: 0000000000000000 R09: 00007ffdc68510e0
R10: 0000000000000000 R11: 0000000000000293 R12: 00007f3284144971
R13: 00007ffdc6851190 R14: 0000000000000000 R15: 00007ffdc6851860

05:42PM

>
> msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
> if (!msg)
> @@ -1078,9 +1084,8 @@ static void devlink_rate_notify(struct devlink_rate *devlink_rate,
> return;
> }
>
> - genlmsg_multicast_netns(&devlink_nl_family,
> - devlink_net(devlink_rate->devlink), msg, 0,
> - DEVLINK_MCGRP_CONFIG, GFP_KERNEL);
> + genlmsg_multicast_netns(&devlink_nl_family, devlink_net(devlink), msg,
> + 0, DEVLINK_MCGRP_CONFIG, GFP_KERNEL);
> }
>
> static int devlink_nl_cmd_rate_get_dumpit(struct sk_buff *msg,
> @@ -4150,6 +4155,7 @@ static void __devlink_flash_update_notify(struct devlink *devlink,
> WARN_ON(cmd != DEVLINK_CMD_FLASH_UPDATE &&
> cmd != DEVLINK_CMD_FLASH_UPDATE_END &&
> cmd != DEVLINK_CMD_FLASH_UPDATE_STATUS);
> + WARN_ON(!xa_get_mark(&devlinks, devlink->index, DEVLINK_REGISTERED));
>
> msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
> if (!msg)
> @@ -5145,17 +5151,18 @@ static void devlink_nl_region_notify(struct devlink_region *region,
> struct devlink_snapshot *snapshot,
> enum devlink_command cmd)
> {
> + struct devlink *devlink = region->devlink;
> struct sk_buff *msg;
>
> WARN_ON(cmd != DEVLINK_CMD_REGION_NEW && cmd != DEVLINK_CMD_REGION_DEL);
> + WARN_ON(!xa_get_mark(&devlinks, devlink->index, DEVLINK_REGISTERED));
>
> msg = devlink_nl_region_notify_build(region, snapshot, cmd, 0, 0);
> if (IS_ERR(msg))
> return;
>
> - genlmsg_multicast_netns(&devlink_nl_family,
> - devlink_net(region->devlink), msg, 0,
> - DEVLINK_MCGRP_CONFIG, GFP_KERNEL);
> + genlmsg_multicast_netns(&devlink_nl_family, devlink_net(devlink), msg,
> + 0, DEVLINK_MCGRP_CONFIG, GFP_KERNEL);
> }
>
> /**
> @@ -6920,10 +6927,12 @@ devlink_nl_health_reporter_fill(struct sk_buff *msg,
> static void devlink_recover_notify(struct devlink_health_reporter *reporter,
> enum devlink_command cmd)
> {
> + struct devlink *devlink = reporter->devlink;
> struct sk_buff *msg;
> int err;
>
> WARN_ON(cmd != DEVLINK_CMD_HEALTH_REPORTER_RECOVER);
> + WARN_ON(!xa_get_mark(&devlinks, devlink->index, DEVLINK_REGISTERED));
>
> msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
> if (!msg)
> @@ -6935,9 +6944,8 @@ static void devlink_recover_notify(struct devlink_health_reporter *reporter,
> return;
> }
>
> - genlmsg_multicast_netns(&devlink_nl_family,
> - devlink_net(reporter->devlink),
> - msg, 0, DEVLINK_MCGRP_CONFIG, GFP_KERNEL);
> + genlmsg_multicast_netns(&devlink_nl_family, devlink_net(devlink), msg,
> + 0, DEVLINK_MCGRP_CONFIG, GFP_KERNEL);
> }
>
> void
> @@ -8955,6 +8963,68 @@ struct devlink *devlink_alloc_ns(const struct devlink_ops *ops,
> }
> EXPORT_SYMBOL_GPL(devlink_alloc_ns);
>
> +static void
> +devlink_trap_policer_notify(struct devlink *devlink,
> + const struct devlink_trap_policer_item *policer_item,
> + enum devlink_command cmd);
> +static void
> +devlink_trap_group_notify(struct devlink *devlink,
> + const struct devlink_trap_group_item *group_item,
> + enum devlink_command cmd);
> +static void devlink_trap_notify(struct devlink *devlink,
> + const struct devlink_trap_item *trap_item,
> + enum devlink_command cmd);
> +
> +static void devlink_notify_register(struct devlink *devlink)
> +{
> + struct devlink_trap_policer_item *policer_item;
> + struct devlink_trap_group_item *group_item;
> + struct devlink_trap_item *trap_item;
> + struct devlink_port *devlink_port;
> +
> + devlink_notify(devlink, DEVLINK_CMD_NEW);
> + list_for_each_entry(devlink_port, &devlink->port_list, list)
> + devlink_port_notify(devlink_port, DEVLINK_CMD_PORT_NEW);
> +
> + list_for_each_entry(policer_item, &devlink->trap_policer_list, list)
> + devlink_trap_policer_notify(devlink, policer_item,
> + DEVLINK_CMD_TRAP_POLICER_NEW);
> +
> + list_for_each_entry(group_item, &devlink->trap_group_list, list)
> + devlink_trap_group_notify(devlink, group_item,
> + DEVLINK_CMD_TRAP_GROUP_NEW);
> +
> + list_for_each_entry(trap_item, &devlink->trap_list, list)
> + devlink_trap_notify(devlink, trap_item, DEVLINK_CMD_TRAP_NEW);
> +
> + devlink_params_publish(devlink);
> +}
> +
> +static void devlink_notify_unregister(struct devlink *devlink)
> +{
> + struct devlink_trap_policer_item *policer_item;
> + struct devlink_trap_group_item *group_item;
> + struct devlink_trap_item *trap_item;
> + struct devlink_port *devlink_port;
> +
> + devlink_params_unpublish(devlink);
> +
> + list_for_each_entry_reverse(trap_item, &devlink->trap_list, list)
> + devlink_trap_notify(devlink, trap_item, DEVLINK_CMD_TRAP_DEL);
> +
> + list_for_each_entry_reverse(group_item, &devlink->trap_group_list, list)
> + devlink_trap_group_notify(devlink, group_item,
> + DEVLINK_CMD_TRAP_GROUP_DEL);
> + list_for_each_entry_reverse(policer_item, &devlink->trap_policer_list,
> + list)
> + devlink_trap_policer_notify(devlink, policer_item,
> + DEVLINK_CMD_TRAP_POLICER_DEL);
> +
> + list_for_each_entry_reverse(devlink_port, &devlink->port_list, list)
> + devlink_port_notify(devlink_port, DEVLINK_CMD_PORT_DEL);
> + devlink_notify(devlink, DEVLINK_CMD_DEL);
> +}
> +
> /**
> * devlink_register - Register devlink instance
> *
> @@ -8964,7 +9034,7 @@ void devlink_register(struct devlink *devlink)
> {
> mutex_lock(&devlink_mutex);
> xa_set_mark(&devlinks, devlink->index, DEVLINK_REGISTERED);
> - devlink_notify(devlink, DEVLINK_CMD_NEW);
> + devlink_notify_register(devlink);
> mutex_unlock(&devlink_mutex);
> }
> EXPORT_SYMBOL_GPL(devlink_register);
> @@ -8982,7 +9052,7 @@ void devlink_unregister(struct devlink *devlink)
> mutex_lock(&devlink_mutex);
> WARN_ON(devlink_reload_supported(devlink->ops) &&
> devlink->reload_enabled);
> - devlink_notify(devlink, DEVLINK_CMD_DEL);
> + devlink_notify_unregister(devlink);
> xa_clear_mark(&devlinks, devlink->index, DEVLINK_REGISTERED);
> mutex_unlock(&devlink_mutex);
> }
> @@ -10086,6 +10156,9 @@ void devlink_params_publish(struct devlink *devlink)
> {
> struct devlink_param_item *param_item;
>
> + if (!xa_get_mark(&devlinks, devlink->index, DEVLINK_REGISTERED))
> + return;
> +
> list_for_each_entry(param_item, &devlink->param_list, list) {
> if (param_item->published)
> continue;
> @@ -10631,6 +10704,8 @@ devlink_trap_group_notify(struct devlink *devlink,
>
> WARN_ON_ONCE(cmd != DEVLINK_CMD_TRAP_GROUP_NEW &&
> cmd != DEVLINK_CMD_TRAP_GROUP_DEL);
> + if (!xa_get_mark(&devlinks, devlink->index, DEVLINK_REGISTERED))
> + return;
>
> msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
> if (!msg)
> @@ -10672,6 +10747,8 @@ static void devlink_trap_notify(struct devlink *devlink,
>
> WARN_ON_ONCE(cmd != DEVLINK_CMD_TRAP_NEW &&
> cmd != DEVLINK_CMD_TRAP_DEL);
> + if (!xa_get_mark(&devlinks, devlink->index, DEVLINK_REGISTERED))
> + return;
>
> msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
> if (!msg)
> @@ -11053,6 +11130,8 @@ devlink_trap_policer_notify(struct devlink *devlink,
>
> WARN_ON_ONCE(cmd != DEVLINK_CMD_TRAP_POLICER_NEW &&
> cmd != DEVLINK_CMD_TRAP_POLICER_DEL);
> + if (!xa_get_mark(&devlinks, devlink->index, DEVLINK_REGISTERED))
> + return;
>
> msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
> if (!msg)
>