From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id EEF4B38AC88 for ; Fri, 14 Aug 2026 19:17:59 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=198.175.65.19 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786735086; cv=none; b=htv6E2tw0MNn24dDDabEnJuKB2Pnt2bclJiUG5pXART/xOksBQtasMjgemDWXM6ExpXKm23VoTUlTZOFzk+iln58+c6vlf5defy7VvRF/HH253+FqnVDfzmfO3fcJSn5aCG1x24wAOUDJh7AUOEUO9WLC4n0vWa5Ix2qDcFzcXc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786735086; c=relaxed/simple; bh=aIy6AHu4mu2ezMCSPBSytPfjGUv570iE05jtc+f2OvY=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=IyOK57BSXDAq3QMqqqNeyqBFHyDWtbmLIvqofVhdT6HA85kv50REhOGuGzWDZ67UcViEQw+SpbXLzjTrpOUSC04K5a456q+i0JOHDALVUOnzON1hJxfooC1P3n7Xhbid+0wTBORWIv8RYHbId1KkLmFanGZsNBiUiIlu96nYHkk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com; spf=pass smtp.mailfrom=intel.com; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b=ZpyaWOAh; arc=none smtp.client-ip=198.175.65.19 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="ZpyaWOAh" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1786735081; x=1818271081; h=date:from:to:cc:subject:message-id:references: mime-version:in-reply-to; bh=aIy6AHu4mu2ezMCSPBSytPfjGUv570iE05jtc+f2OvY=; b=ZpyaWOAhgQL01BFv8SZcxI0li3LQ0nG1Bxk792lZNv0LkeasOjw9tQno LUzlbXtlS2yuyHdsxeSOZt1noeQ9gXXXOJRH/c8v8oxIwIQUlZFMnQDgm o0P50cDArQXKywuVZEDXukv/pctPpfXaEOvn5LCYBfq5gnFCrgPTnyPB7 kNibifmiKMe4QxZzMCzsNwDjR7hTPn7qqnQhwcJO0mBVY9tvG4KVYrOnc S1qF4/txEwfDt8ehC37v+0UtdSJom4SmEkSwnqj+O3gPOgQhZZAhnOSRc p0tL5wGDk55AE2E10QMvNmLWamy2lKRyLNehG/uXJFlEZzbPSnwlc0H9n g==; X-CSE-ConnectionGUID: oFVRkMb/QWmZQpsMAMwSeA== X-CSE-MsgGUID: tpXPDlFVQDKvaSJbtlWJHA== X-IronPort-AV: E=McAfee;i="6800,10657,11875"; a="87241405" X-IronPort-AV: E=Sophos;i="6.25,222,1779174000"; d="scan'208";a="87241405" Received: from fmviesa003.fm.intel.com ([10.60.135.143]) by orvoesa111.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 14 Aug 2026 12:17:58 -0700 X-CSE-ConnectionGUID: xAUh4cfPRsmoli1n/MyUHA== X-CSE-MsgGUID: x4cVu1NaQRmLhQGA6npvtg== X-ExtLoop1: 1 Received: from lkp-server01.sh.intel.com (HELO 6eda058d650d) ([10.239.97.150]) by fmviesa003.fm.intel.com with ESMTP; 14 Aug 2026 12:17:55 -0700 Received: from kbuild by 6eda058d650d with local (Exim 4.98.2) (envelope-from ) id 1wuxPc-00000000Zuu-2LnO; Fri, 14 Aug 2026 19:17:52 +0000 Date: Sat, 15 Aug 2026 03:17:08 +0800 From: kernel test robot To: Aaron Tomlin , akpm@linux-foundation.org, lance.yang@linux.dev, mhiramat@kernel.org, pmladek@suse.com Cc: oe-kbuild-all@lists.linux.dev, linux-kernel@vger.kernel.org, david.laight.linux@gmail.com, atomlin@atomlin.com, neelx@suse.com, sean@ashe.io, chjohnst@gmail.com, steve@abita.co, mproche@gmail.com, nick.lange@gmail.com Subject: Re: [PATCH v2] hung_task: Add per-round stack trace deduplication Message-ID: <202608150327.OJ0wc1wA-lkp@intel.com> References: <20260620013559.1537893-1-atomlin@atomlin.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20260620013559.1537893-1-atomlin@atomlin.com> Hi Aaron, kernel test robot noticed the following build errors: [auto build test ERROR on akpm-mm/mm-everything] [also build test ERROR on linus/master v7.2-rc7 next-20260813] [cannot apply to linux-review/Aaron-Tomlin/hung_task-Add-per-round-stack-trace-deduplication/20260618-025656] [If your patch is applied to the wrong git tree, kindly drop us a note. And when submitting patch, we suggest to use '--base' as documented in https://git-scm.com/docs/git-format-patch#_base_tree_information] url: https://github.com/intel-lab-lkp/linux/commits/Aaron-Tomlin/hung_task-Add-per-round-stack-trace-deduplication/20260814-211006 base: https://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm.git mm-everything patch link: https://lore.kernel.org/r/20260620013559.1537893-1-atomlin%40atomlin.com patch subject: [PATCH v2] hung_task: Add per-round stack trace deduplication config: alpha-allmodconfig (https://download.01.org/0day-ci/archive/20260815/202608150327.OJ0wc1wA-lkp@intel.com/config) compiler: alpha-linux-gcc (GCC) 16.1.0 reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20260815/202608150327.OJ0wc1wA-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 | Closes: https://lore.kernel.org/oe-kbuild-all/202608150327.OJ0wc1wA-lkp@intel.com/ All errors (new ones prefixed by >>): In file included from : kernel/hung_task.c: In function 'check_hung_uninterruptible_tasks': >> kernel/hung_task.c:388:72: error: 'sysctl_hung_task_dedup' undeclared (first use in this function); did you mean 'sysctl_hung_task_panic'? 388 | bool dedup_enabled = IS_ENABLED(CONFIG_STACKTRACE) ? READ_ONCE(sysctl_hung_task_dedup) : 0; | ^~~~~~~~~~~~~~~~~~~~~~ include/linux/compiler_types.h:682:23: note: in definition of macro '__compiletime_assert' 682 | if (!(condition)) \ | ^~~~~~~~~ include/linux/compiler_types.h:702:9: note: in expansion of macro '_compiletime_assert' 702 | _compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__) | ^~~~~~~~~~~~~~~~~~~ include/asm-generic/rwonce.h:36:9: note: in expansion of macro 'compiletime_assert' 36 | compiletime_assert(__native_word(t) || sizeof(t) == sizeof(long long), \ | ^~~~~~~~~~~~~~~~~~ include/asm-generic/rwonce.h:36:28: note: in expansion of macro '__native_word' 36 | compiletime_assert(__native_word(t) || sizeof(t) == sizeof(long long), \ | ^~~~~~~~~~~~~ include/asm-generic/rwonce.h:49:9: note: in expansion of macro 'compiletime_assert_rwonce_type' 49 | compiletime_assert_rwonce_type(x); \ | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ kernel/hung_task.c:388:62: note: in expansion of macro 'READ_ONCE' 388 | bool dedup_enabled = IS_ENABLED(CONFIG_STACKTRACE) ? READ_ONCE(sysctl_hung_task_dedup) : 0; | ^~~~~~~~~ kernel/hung_task.c:388:72: note: each undeclared identifier is reported only once for each function it appears in include/linux/compiler_types.h:682:23: note: in definition of macro '__compiletime_assert' 682 | if (!(condition)) \ | ^~~~~~~~~ include/linux/compiler_types.h:702:9: note: in expansion of macro '_compiletime_assert' 702 | _compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__) | ^~~~~~~~~~~~~~~~~~~ include/asm-generic/rwonce.h:36:9: note: in expansion of macro 'compiletime_assert' 36 | compiletime_assert(__native_word(t) || sizeof(t) == sizeof(long long), \ | ^~~~~~~~~~~~~~~~~~ include/asm-generic/rwonce.h:36:28: note: in expansion of macro '__native_word' 36 | compiletime_assert(__native_word(t) || sizeof(t) == sizeof(long long), \ | ^~~~~~~~~~~~~ include/asm-generic/rwonce.h:49:9: note: in expansion of macro 'compiletime_assert_rwonce_type' 49 | compiletime_assert_rwonce_type(x); \ | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ kernel/hung_task.c:388:62: note: in expansion of macro 'READ_ONCE' 388 | bool dedup_enabled = IS_ENABLED(CONFIG_STACKTRACE) ? READ_ONCE(sysctl_hung_task_dedup) : 0; | ^~~~~~~~~ vim +388 kernel/hung_task.c 375 376 /* 377 * Check whether a TASK_UNINTERRUPTIBLE does not get woken up for 378 * a really long time. If that happens, print out a warning. 379 */ 380 static void check_hung_uninterruptible_tasks(unsigned long timeout) 381 { 382 int max_count = sysctl_hung_task_check_count; 383 unsigned long last_break = jiffies; 384 struct task_struct *g, *t; 385 unsigned long this_round_count; 386 int need_warning = sysctl_hung_task_warnings; 387 unsigned long si_mask = hung_task_si_mask; > 388 bool dedup_enabled = IS_ENABLED(CONFIG_STACKTRACE) ? READ_ONCE(sysctl_hung_task_dedup) : 0; 389 390 /* 391 * If the system crashed already then all bets are off, 392 * do not report extra hung tasks: 393 */ 394 if (test_taint(TAINT_DIE) || did_panic) 395 return; 396 397 /* 398 * Reset the de-duplicator hash table for this new detection round. 399 * This prevents stale hashes from permanently suppressing. 400 */ 401 if (dedup_enabled) 402 hung_task_dedup_flush(); 403 404 this_round_count = 0; 405 rcu_read_lock(); 406 for_each_process_thread(g, t) { 407 if (!max_count--) 408 goto unlock; 409 if (time_after(jiffies, last_break + HUNG_TASK_LOCK_BREAK)) { 410 if (!rcu_lock_break(g, t)) 411 goto unlock; 412 last_break = jiffies; 413 } 414 415 if (task_is_hung(t, timeout)) { 416 /* 417 * Increment the global counter so that userspace could 418 * start migrating tasks ASAP. But count the current 419 * round separately because userspace could reset 420 * the global counter at any time. 421 */ 422 atomic_long_inc(&sysctl_hung_task_detect_count); 423 this_round_count++; 424 hung_task_info(t, timeout, this_round_count, dedup_enabled); 425 } 426 } 427 unlock: 428 rcu_read_unlock(); 429 430 if (!this_round_count) 431 return; 432 433 if (need_warning || hung_task_call_panic) { 434 si_mask |= SYS_INFO_LOCKS; 435 436 if (sysctl_hung_task_all_cpu_backtrace) 437 si_mask |= SYS_INFO_ALL_BT; 438 } 439 440 sys_info(si_mask); 441 442 if (hung_task_call_panic) 443 panic("hung_task: blocked tasks"); 444 } 445 -- 0-DAY CI Kernel Test Service https://github.com/intel/lkp-tests/wiki