[trace:bootconfig/for-next 16/16] init/main.c:437:20: warning: stack frame size (4192) exceeds limit (2048) in 'bootconfig_apply_early_params'

[kernel test robot <lkp@intel.com>]

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace bootconfig/for-next
head:   1a427f2a710583872b6176ea8378e0a1a8719fc4
commit: 1a427f2a710583872b6176ea8378e0a1a8719fc4 [16/16] bootconfig: Apply early options from embedded config
config: loongarch-allmodconfig (https://download.01.org/0day-ci/archive/20260325/202603251010.5Ui0yrB2-lkp@intel.com/config)
compiler: clang version 19.1.7 (https://github.com/llvm/llvm-project cd708029e0b2869e80abe31ddb175f7c35361f90)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20260325/202603251010.5Ui0yrB2-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202603251010.5Ui0yrB2-lkp@intel.com/

All warnings (new ones prefixed by >>):

>> init/main.c:437:20: warning: stack frame size (4192) exceeds limit (2048) in 'bootconfig_apply_early_params' [-Wframe-larger-than]
     437 | static void __init bootconfig_apply_early_params(void)
         |                    ^
   1 warning generated.


vim +/bootconfig_apply_early_params +437 init/main.c

   416	
   417	/*
   418	 * do_early_param() is defined later in this file but called from
   419	 * bootconfig_apply_early_params() below, so we need a forward declaration.
   420	 */
   421	static int __init do_early_param(char *param, char *val,
   422					 const char *unused, void *arg);
   423	
   424	/*
   425	 * bootconfig_apply_early_params - dispatch kernel.* keys from the embedded
   426	 * bootconfig as early_param() calls.
   427	 *
   428	 * early_param() handlers must run before most of the kernel initialises
   429	 * (e.g. before the GIC driver reads irqchip.gicv3_pseudo_nmi).  A bootconfig
   430	 * attached to the initrd arrives too late for this because the initrd is not
   431	 * mapped yet when early params are processed.  The embedded bootconfig lives
   432	 * in the kernel image itself (.init.data), so it is always reachable.
   433	 *
   434	 * This function is called from setup_boot_config() which runs in
   435	 * start_kernel() before parse_early_param(), making the timing correct.
   436	 */
 > 437	static void __init bootconfig_apply_early_params(void)
   438	{
   439		char val_buf[COMMAND_LINE_SIZE];
   440		struct xbc_node *knode, *root;
   441		const char *val;
   442	
   443		root = xbc_find_node("kernel");
   444		if (!root)
   445			return;
   446	
   447		/*
   448		 * Keys that do not match any early_param() handler are silently
   449		 * ignored — do_early_param() always returns 0.
   450		 */
   451		xbc_node_for_each_key_value(root, knode, val) {
   452			if (xbc_node_compose_key_after(root, knode, xbc_namebuf, XBC_KEYLEN_MAX) < 0)
   453				continue;
   454	
   455			if (!val) {
   456				do_early_param(xbc_namebuf, NULL, NULL, NULL);
   457				continue;
   458			}
   459	
   460			/*
   461			 * We need to copy const char *val to a char pointer,
   462			 * which is what do_early_param() need, given it might
   463			 * call strsep(), strtok() later.
   464			 */
   465			strscpy(val_buf, val, sizeof(val_buf));
   466			do_early_param(xbc_namebuf, val_buf, NULL, NULL);
   467		}
   468	}
   469	

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