• Li RongQing's avatar
    rtnetlink: introduce nlmsg_new_large and use it in rtnl_getlink · ac40916a
    Li RongQing authored
    if a PF has 256 or more VFs, ip link command will allocate an order 3
    memory or more, and maybe trigger OOM due to memory fragment,
    the VFs needed memory size is computed in rtnl_vfinfo_size.
    
    so introduce nlmsg_new_large which calls netlink_alloc_large_skb in
    which vmalloc is used for large memory, to avoid the failure of
    allocating memory
    
        ip invoked oom-killer: gfp_mask=0xc2cc0(GFP_KERNEL|__GFP_NOWARN|\
    	__GFP_COMP|__GFP_NOMEMALLOC), order=3, oom_score_adj=0
        CPU: 74 PID: 204414 Comm: ip Kdump: loaded Tainted: P           OE
        Call Trace:
        dump_stack+0x57/0x6a
        dump_header+0x4a/0x210
        oom_kill_process+0xe4/0x140
        out_of_memory+0x3e8/0x790
        __alloc_pages_slowpath.constprop.116+0x953/0xc50
        __alloc_pages_nodemask+0x2af/0x310
        kmalloc_large_node+0x38/0xf0
        __kmalloc_node_track_caller+0x417/0x4d0
        __kmalloc_reserve.isra.61+0x2e/0x80
        __alloc_skb+0x82/0x1c0
        rtnl_getlink+0x24f/0x370
        rtnetlink_rcv_msg+0x12c/0x350
        netlink_rcv_skb+0x50/0x100
        netlink_unicast+0x1b2/0x280
        netlink_sendmsg+0x355/0x4a0
        sock_sendmsg+0x5b/0x60
        ____sys_sendmsg+0x1ea/0x250
        ___sys_sendmsg+0x88/0xd0
        __sys_sendmsg+0x5e/0xa0
        do_syscall_64+0x33/0x40
        entry_SYSCALL_64_after_hwframe+0x44/0xa9
        RIP: 0033:0x7f95a65a5b70
    
    Cc: Yunsheng Lin <linyunsheng@huawei.com>
    Signed-off-by: default avatarLi RongQing <lirongqing@baidu.com>
    Link: https://lore.kernel.org/r/20231115120108.3711-1-lirongqing@baidu.comSigned-off-by: default avatarJakub Kicinski <kuba@kernel.org>
    ac40916a
rtnetlink.c 163 KB