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 A27D1175D3E for ; Mon, 12 Aug 2024 12:12:54 +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=1723464774; cv=none; b=d/KW70UzjxjwPEj6AdQFtaoZLN1/S8ncy/2uGlt2ZvxJCl+wjPrnX4BbBT8ob+khzderAaOrS2p4ZTemJp6Nf5wauW1YmJ8EIaKNXALd4+YYJsRdNZqOrRWQxO1hghX1TXkkwAt1hLdtPA8IPg5156Gx0PTbqXcyDA691yknc3g= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1723464774; c=relaxed/simple; bh=UxuOxATv/+xEXZWufWXlBWEd0v9r933clSXVZayzCEg=; h=Subject:To:Cc:From:Date:Message-ID:MIME-Version:Content-Type; b=dNoN6mEADQQlgzygeY+MXNbClc0br8euVjbryzet01m/IQPbrEhpSrz5bgFOVasPE1PNrqi9ux+5OLnrKFlWkIHLVBlPGUlk8wSqV+3/QiHNRI8BVBpFxTblDEGv0UI0TGqozWrasKPx/xDJdcIyVAiYb01SEmeJBmy4iEvA+6c= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=J2NV6dMm; 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="J2NV6dMm" Received: by smtp.kernel.org (Postfix) with ESMTPSA id B4794C32782; Mon, 12 Aug 2024 12:12:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1723464774; bh=UxuOxATv/+xEXZWufWXlBWEd0v9r933clSXVZayzCEg=; h=Subject:To:Cc:From:Date:From; b=J2NV6dMmOF5OzIAF+z60sPfyBPL0SqSmm8PvU5EEr4h+3+s/bW44ulBr++4ddpBiD G6RK2/rsLOsuvPLo4CSQfCOet3Mmt3yecuKTmEgzIBrCRJB6FVVr9if5jLKZbFMxpK u5QyEF+HsOlo3QfovpNo+KlTiczEP0h89bSmLYVo= Subject: FAILED: patch "[PATCH] sched/smt: Fix unbalance sched_smt_present dec/inc" failed to apply to 4.19-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 14:12:41 +0200 Message-ID: <2024081240-safeguard-refract-aef2@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 4.19-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-4.19.y git checkout FETCH_HEAD git cherry-pick -x e22f910a26cc2a3ac9c66b8e935ef2a7dd881117 # git commit -s git send-email --to '' --in-reply-to '2024081240-safeguard-refract-aef2@gregkh' --subject-prefix 'PATCH 4.19.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()") c5511d03ec09 ("sched/smt: Make sched_smt_present track topology") 1f351d7f7590 ("sched: sched.h: make rq locking and clock functions available in stats.h") 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);