From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 A493217994F for ; Mon, 12 Aug 2024 12:12:51 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1723464771; cv=none; b=VHPMYbcKtOgrODJkNS5h8ytGLFrZJhqsDJZhikUyTBRtZJMbxosoSLLE4O8MVrSj2WxQj16VzxpuKxwQrgfi0UEC3rh2Cfm8Rz1yIlorRNOzcPSl5DDfcYBCOsTgLWqq6nWzNX2hjMhm/afFiotBMbYaN5SxNgyzah0fJQ+Qbbo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1723464771; c=relaxed/simple; bh=Zd5cCC9KGzQZg8nQziJ5kou4JMfjC7iWpjt/5LWvzq0=; h=Subject:To:Cc:From:Date:Message-ID:MIME-Version:Content-Type; b=onxCnch0VpEitDZhQOscCEVhNXSNFmPBXK9O0HQM4UNxOdJiZ9435IQ6Fu9wb00954UGssKOZ0SVxMSAj4Eo+5aJEmAg3xBYMUsYlkMc82YDeJre5jw1CWJLcGtr2r5IkA5uHhAMiIk6xCK1vUfsYJsaFW0ZoLJ9hgSt5VVHMFY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=1elutS9B; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="1elutS9B" Received: by smtp.kernel.org (Postfix) with ESMTPSA id AD7B6C32782; Mon, 12 Aug 2024 12:12:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1723464771; bh=Zd5cCC9KGzQZg8nQziJ5kou4JMfjC7iWpjt/5LWvzq0=; h=Subject:To:Cc:From:Date:From; b=1elutS9BeEFSMxDSZYB66XvoO5M8NjZX8K+4S0IPhRpbG57Hy1LxjSrwjzMhssu8B PXIELt+P0U48BhvElzAO+cdbIx8Say2dYZY1OKrAuGQGvcA/pMB6zALNLmNKK1sv5U bWLlioDHQKk1vPcdm/e1MUA/sQdzpJMNIDA2Dke0= Subject: FAILED: patch "[PATCH] sched/smt: Fix unbalance sched_smt_present dec/inc" failed to apply to 5.4-stable tree To: yangyingliang@huawei.com,peterz@infradead.org,tim.c.chen@linux.intel.com,yu.c.chen@intel.com Cc: From: Date: Mon, 12 Aug 2024 14:12:40 +0200 Message-ID: <2024081239-cubbyhole-wise-c8d1@gregkh> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit The patch below does not apply to the 5.4-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to . To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.4.y git checkout FETCH_HEAD git cherry-pick -x e22f910a26cc2a3ac9c66b8e935ef2a7dd881117 # git commit -s git send-email --to '' --in-reply-to '2024081239-cubbyhole-wise-c8d1@gregkh' --subject-prefix 'PATCH 5.4.y' HEAD^.. Possible dependencies: e22f910a26cc ("sched/smt: Fix unbalance sched_smt_present dec/inc") 2558aacff858 ("sched/hotplug: Ensure only per-cpu kthreads run during hotplug") 565790d28b1e ("sched: Fix balance_callback()") thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From e22f910a26cc2a3ac9c66b8e935ef2a7dd881117 Mon Sep 17 00:00:00 2001 From: Yang Yingliang Date: Wed, 3 Jul 2024 11:16:08 +0800 Subject: [PATCH] sched/smt: Fix unbalance sched_smt_present dec/inc I got the following warn report while doing stress test: jump label: negative count! WARNING: CPU: 3 PID: 38 at kernel/jump_label.c:263 static_key_slow_try_dec+0x9d/0xb0 Call Trace: __static_key_slow_dec_cpuslocked+0x16/0x70 sched_cpu_deactivate+0x26e/0x2a0 cpuhp_invoke_callback+0x3ad/0x10d0 cpuhp_thread_fun+0x3f5/0x680 smpboot_thread_fn+0x56d/0x8d0 kthread+0x309/0x400 ret_from_fork+0x41/0x70 ret_from_fork_asm+0x1b/0x30 Because when cpuset_cpu_inactive() fails in sched_cpu_deactivate(), the cpu offline failed, but sched_smt_present is decremented before calling sched_cpu_deactivate(), it leads to unbalanced dec/inc, so fix it by incrementing sched_smt_present in the error path. Fixes: c5511d03ec09 ("sched/smt: Make sched_smt_present track topology") Cc: stable@kernel.org Signed-off-by: Yang Yingliang Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Chen Yu Reviewed-by: Tim Chen Link: https://lore.kernel.org/r/20240703031610.587047-3-yangyingliang@huaweicloud.com diff --git a/kernel/sched/core.c b/kernel/sched/core.c index acc04ed9dbc2..949473e414f9 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -8009,6 +8009,7 @@ int sched_cpu_deactivate(unsigned int cpu) sched_update_numa(cpu, false); ret = cpuset_cpu_inactive(cpu); if (ret) { + sched_smt_present_inc(cpu); balance_push_set(cpu, false); set_cpu_active(cpu, true); sched_update_numa(cpu, true);