RT-Thread / RT-Thread/rt-thread

[Bug] Thread pause error in rt_thread_mdelay function

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Description

RT-Thread Version

5.2.0 commit 2f559906d6202c27142237ab4b1d893034a5b7c3

Hardware Type/Architectures

VEXPRESS_A9

Develop Toolchain

GCC

Describe the bug

Hi, i encountered an error in rt_thread_mdelay function.

Describe the bug

Incorrect message handling or mailbox state causes kernel stop in tcpip thread

Steps to reproduce

1.Build RT-Thread
2.Use the following command to start the kernel with QEMU:

qemu-system-arm \
    -M vexpress-a9 \
    -smp 2 \
    -m 4096M \
    -kernel /path/to/rt-thread/bsp/qemu-vexpress-a9/rtthread.bin \
    -drive if=sd,file=/path/to/rt-thread/bsp/qemu-vexpress-a9/sd.bin,format=raw \
    -nographic \
    -semihosting \

3.Use the functions and parameters provided in the ’Test case‘ section for testing

Source code location

/root/rtthread/rt-thread/components/net/lwip/port/sys_arch.c : sys_arch_mbox_fetch : 423 :

    /*When the waiting msg is generated by the application through signaling mechanisms,
    only by using interruptible mode can the program be made runnable again*/
    ret = rt_mb_recv_interruptible(*mbox, (rt_ubase_t *)msg, t); // 423
    if(ret != RT_EOK)
    {
        return SYS_ARCH_TIMEOUT;
    }
Test case

syz_thread_delay_ms()

long syz_thread_delay_ms(volatile int ms) {
    if (ms <= 0) {
        return -1;
    }
    rt_thread_mdelay((rt_int32_t)ms);
    return 0;
}
Backtrace upon hitting the bug
#executing syz_thread_delay_ms (0xb688)
2024/09/04 15:14:48 Syscall execution is ok
2024/09/04 15:14:51 qemu run inst merger err: execution timed out
2024/09/04 15:14:51 Received stop signal, requires feedback = true
2024/09/04 15:14:51 running diagnose
2024/09/04 15:14:51 VM-0 failed reading regs: dial tcp 127.0.0.1:24177: connect: connection refused
2024/09/04 15:14:51 VM-0 failed reading regs: dial tcp 127.0.0.1:24177: connect: connection refused
2024/09/04 15:14:51 Stack frames at BUG: unexpected stop:
2024/09/04 15:14:51 Level: 0: 1611238748, /root/kcov.c : __sanitizer_cov_trace_pc : 71 : 
2024/09/04 15:14:51 Level: 1: 1611495348, /root/rtthread/rt-thread/src/scheduler_up.c : rt_schedule : 238 : 
2024/09/04 15:14:51 Level: 2: 1611445488, /root/rtthread/rt-thread/src/ipc.c : _rt_mb_recv : 2912 : 
2024/09/04 15:14:51 Level: 3: 1611446256, /root/rtthread/rt-thread/src/ipc.c : rt_mb_recv_interruptible : 2974 : 
2024/09/04 15:14:51 Level: 4: 1611130960, /root/rtthread/rt-thread/components/net/lwip/port/sys_arch.c : sys_arch_mbox_fetch : 423 : 
2024/09/04 15:14:51 Level: 5: 1611104436, /root/rtthread/rt-thread/components/net/lwip/lwip-2.0.3/src/core/timeouts.c : sys_timeouts_mbox_fetch : 416 : 
2024/09/04 15:14:51 Level: 6: 1610890752, /root/rtthread/rt-thread/components/net/lwip/lwip-2.0.3/src/api/tcpip.c : tcpip_thread : 101 : 
2024/09/04 15:14:51 Level: 7: 1611546932, /root/rtthread/rt-thread/libcpu/arm/cortex-a/start_gcc.S : _thread_start : 628 : 

I would greatly appreciate it if you could kindly inform me of any mistakes in the previous issues.

Other additional context

No response

Contributor guide

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First steps

  1. Read the whole issue, then the project's contributing guide.
  2. Comment on the issue to say you are picking it up — it saves two people doing the same work.
  3. Fork the repository and make your change on a branch.
  4. Open a pull request that references the issue number.

Research direction

Reproduce the timeout with the provided QEMU VEXPRESS_A9 command and syz_thread_delay_ms test case. Start in components/net/lwip/port/sys_arch.c at sys_arch_mbox_fetch, then trace rt_mb_recv_interruptible and _rt_mb_recv in src/ipc.c against the tcpip_thread backtrace. Done means identifying the mailbox or scheduling failure and demonstrating that the kernel no longer stops under the reported case.

Written by the indexing model from the issue text.

Assessment

Tech stack
c
Domain
networking, operating-systems
Issue type
Bug
Difficulty
4/5
Estimated time
3-5 days
Activity status
Stale
Clarity
Needs clarification
Newbie friendliness
25/100

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