6.17-stable review patch. If anyone has any objections, please let me know.
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From: Hengqi Chen hengqi.chen@gmail.com
commit e82406c7cbdd368c5459b8a45e118811d2ba0794 upstream.
The current implementation does not support struct argument. This causes a oops when running bpf selftest:
$ ./test_progs -a tracing_struct Oops[#1]: CPU -1 Unable to handle kernel paging request at virtual address 0000000000000018, era == 9000000085bef268, ra == 90000000844f3938 rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 1-...0: (19 ticks this GP) idle=1094/1/0x4000000000000000 softirq=1380/1382 fqs=801 rcu: (detected by 0, t=5252 jiffies, g=1197, q=52 ncpus=4) Sending NMI from CPU 0 to CPUs 1: rcu: rcu_preempt kthread starved for 2495 jiffies! g1197 f0x0 RCU_GP_DOING_FQS(6) ->state=0x0 ->cpu=2 rcu: Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior. rcu: RCU grace-period kthread stack dump: task:rcu_preempt state:I stack:0 pid:15 tgid:15 ppid:2 task_flags:0x208040 flags:0x00000800 Stack : 9000000100423e80 0000000000000402 0000000000000010 90000001003b0680 9000000085d88000 0000000000000000 0000000000000040 9000000087159350 9000000085c2b9b0 0000000000000001 900000008704a000 0000000000000005 00000000ffff355b 00000000ffff355b 0000000000000000 0000000000000004 9000000085d90510 0000000000000000 0000000000000002 7b5d998f8281e86e 00000000ffff355c 7b5d998f8281e86e 000000000000003f 9000000087159350 900000008715bf98 0000000000000005 9000000087036000 900000008704a000 9000000100407c98 90000001003aff80 900000008715c4c0 9000000085c2b9b0 00000000ffff355b 9000000085c33d3c 00000000000000b4 0000000000000000 9000000007002150 00000000ffff355b 9000000084615480 0000000007000002 ... Call Trace: [<9000000085c2a868>] __schedule+0x410/0x1520 [<9000000085c2b9ac>] schedule+0x34/0x190 [<9000000085c33d38>] schedule_timeout+0x98/0x140 [<90000000845e9120>] rcu_gp_fqs_loop+0x5f8/0x868 [<90000000845ed538>] rcu_gp_kthread+0x260/0x2e0 [<900000008454e8a4>] kthread+0x144/0x238 [<9000000085c26b60>] ret_from_kernel_thread+0x28/0xc8 [<90000000844f20e4>] ret_from_kernel_thread_asm+0xc/0x88
rcu: Stack dump where RCU GP kthread last ran: Sending NMI from CPU 0 to CPUs 2: NMI backtrace for cpu 2 skipped: idling at idle_exit+0x0/0x4
Reject it for now.
Cc: stable@vger.kernel.org Fixes: f9b6b41f0cf3 ("LoongArch: BPF: Add basic bpf trampoline support") Tested-by: Vincent Li vincent.mc.li@gmail.com Signed-off-by: Hengqi Chen hengqi.chen@gmail.com Signed-off-by: Huacai Chen chenhuacai@loongson.cn Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- arch/loongarch/net/bpf_jit.c | 6 ++++++ 1 file changed, 6 insertions(+)
--- a/arch/loongarch/net/bpf_jit.c +++ b/arch/loongarch/net/bpf_jit.c @@ -1526,6 +1526,12 @@ static int __arch_prepare_bpf_trampoline if (m->nr_args > LOONGARCH_MAX_REG_ARGS) return -ENOTSUPP;
+ /* FIXME: No support of struct argument */ + for (i = 0; i < m->nr_args; i++) { + if (m->arg_flags[i] & BTF_FMODEL_STRUCT_ARG) + return -ENOTSUPP; + } + if (flags & (BPF_TRAMP_F_ORIG_STACK | BPF_TRAMP_F_SHARE_IPMODIFY)) return -ENOTSUPP;