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       1                 :             : /*
       2                 :             :  * Copyright (c) 2018 Intel Corporation
       3                 :             :  *
       4                 :             :  * SPDX-License-Identifier: Apache-2.0
       5                 :             :  */
       6                 :             : 
       7                 :             : /**
       8                 :             :  * @file
       9                 :             :  * @brief Thread entry
      10                 :             :  *
      11                 :             :  * This file provides the common thread entry function
      12                 :             :  */
      13                 :             : 
      14                 :             : #include <zephyr/kernel.h>
      15                 :             : #include <zephyr/arch/cfi.h>
      16                 :             : #ifdef CONFIG_CURRENT_THREAD_USE_TLS
      17                 :             : #include <zephyr/random/random.h>
      18                 :             : 
      19                 :             : Z_THREAD_LOCAL k_tid_t z_tls_current;
      20                 :             : #endif
      21                 :             : 
      22                 :             : #ifdef CONFIG_STACK_CANARIES_TLS
      23                 :             : extern Z_THREAD_LOCAL volatile uintptr_t __stack_chk_guard;
      24                 :             : #endif /* CONFIG_STACK_CANARIES_TLS */
      25                 :             : 
      26                 :             : /*
      27                 :             :  * Common thread entry point function (used by all threads)
      28                 :             :  *
      29                 :             :  * This routine invokes the actual thread entry point function and passes
      30                 :             :  * it three arguments. It also handles graceful termination of the thread
      31                 :             :  * if the entry point function ever returns.
      32                 :             :  *
      33                 :             :  * This routine does not return, and is marked as such so the compiler won't
      34                 :             :  * generate preamble code that is only used by functions that actually return.
      35                 :             :  */
      36                 :          47 : FUNC_NORETURN void z_thread_entry(k_thread_entry_t entry,
      37                 :             :                                  void *p1, void *p2, void *p3)
      38                 :             : {
      39                 :             : /*
      40                 :             :  * Inform the unwinder that the current return address is undefined.
      41                 :             :  *
      42                 :             :  * This is typically used at points in the code where execution does not
      43                 :             :  * return like a normal function (for example, thread entry routines).
      44                 :             :  * Marking the return address as undefined prevents stack unwinding or
      45                 :             :  * backtrace tools from following a bogus return address, which could
      46                 :             :  * otherwise lead to reading invalid memory and cause faults during
      47                 :             :  * unwinding or debugging.
      48                 :             :  */
      49                 :          47 :         ARCH_CFI_UNDEFINED_RETURN_ADDRESS();
      50                 :             : #ifdef CONFIG_CURRENT_THREAD_USE_TLS
      51                 :             :         z_tls_current = k_sched_current_thread_query();
      52                 :             : #endif
      53                 :             : #ifdef CONFIG_STACK_CANARIES_TLS
      54                 :             :         uintptr_t stack_guard;
      55                 :             : 
      56                 :             :         sys_rand_get((uint8_t *)&stack_guard, sizeof(stack_guard));
      57                 :             :         __stack_chk_guard = stack_guard;
      58                 :             :         __stack_chk_guard <<= 8;
      59                 :             : #endif  /* CONFIG_STACK_CANARIES */
      60                 :          47 :         entry(p1, p2, p3);
      61                 :             : 
      62                 :          46 :         k_thread_abort(k_current_get());
      63                 :             : 
      64                 :             :         /*
      65                 :             :          * Compiler can't tell that k_thread_abort() won't return and issues a
      66                 :             :          * warning unless we tell it that control never gets this far.
      67                 :             :          */
      68                 :             : 
      69                 :             :         CODE_UNREACHABLE; /* LCOV_EXCL_LINE */
      70                 :             : }