From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail3-164.sinamail.sina.com.cn (mail3-164.sinamail.sina.com.cn [202.108.3.164]) (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 6693A1F956 for ; Thu, 3 Jul 2025 01:08:13 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=202.108.3.164 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1751504898; cv=none; b=lE8dpgfRC2idJBzZ9f3brNc+ElSmDwD0ViLiavjJqGEP6yXX1tb9DzDscF+Nw/X66niyVVY8N//EksWdFYWAwCDTpTTjBtT+y2/4iwtOAPS55KxwChnDGjZ2SVTyQqLvGeONl0AFowIuqC7pSRvxFNURYfW2qYBfWr1ITHmTG5o= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1751504898; c=relaxed/simple; bh=SUVlWdQqDyKJ4LhgmTpbGQqJAa4sQ+Phf/BlrfPW6h0=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=Pzvj0xGsrhHoZSlJjaRyCIQlyOeXvLcCPyotpIiuu7lkIMC1wJ1VSKomRCMuYva7gb8PCP81o9QDn/jCAYKLI56vuvnldLJid6Xp5FeqCgnPFrQj5TTn8ej4htKmoxZwLO1uLEdubi7dS2iMKEvGsb/wMRa1whfJ+SUQqHfEEt4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=sina.com; spf=pass smtp.mailfrom=sina.com; dkim=pass (1024-bit key) header.d=sina.com header.i=@sina.com header.b=ude8dWvI; arc=none smtp.client-ip=202.108.3.164 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=sina.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=sina.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=sina.com header.i=@sina.com header.b="ude8dWvI" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sina.com; s=201208; t=1751504893; bh=1jJ//o1g6ALetyXYXwk4Tl4JBYGREwme42sNYEyCAjg=; h=From:Subject:Date:Message-ID; b=ude8dWvIkBhvmNrvzxoZDoY95EGpWER09emEpS6MTX9wd63LXNDpmIkzV3ikbpOP0 DP7/qVqAA38bkfi08gqKgf+GoSyCBvKNfNL3rfY7akB4+3qufxwFZF/iQlIuupYXLC VtpdYLAYpS8OgFwc6X55MYWkGRJYvMHTBn1D0vuc= X-SMAIL-HELO: localhost.localdomain Received: from unknown (HELO localhost.localdomain)([114.249.58.236]) by sina.com (10.54.253.32) with ESMTP id 6865D6AD00000771; Thu, 3 Jul 2025 09:02:39 +0800 (CST) X-Sender: hdanton@sina.com X-Auth-ID: hdanton@sina.com Authentication-Results: sina.com; spf=none smtp.mailfrom=hdanton@sina.com; dkim=none header.i=none; dmarc=none action=none header.from=hdanton@sina.com X-SMAIL-MID: 1764334457055 X-SMAIL-UIID: 325FC3E2E72347A98D65E01A22244399-20250703-090239-1 From: Hillf Danton To: syzbot Cc: linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com Subject: Re: [syzbot] [kernel?] general protection fault in __cpa_flush_tlb Date: Thu, 3 Jul 2025 09:02:26 +0800 Message-ID: <20250703010227.2223-1-hdanton@sina.com> In-Reply-To: <6865460d.a00a0220.270cb1.0001.GAE@google.com> References: Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit > Date: Wed, 02 Jul 2025 07:45:33 -0700 > syzbot found the following issue on: > > HEAD commit: 1343433ed389 Add linux-next specific files for 20250630 > git tree: linux-next > console output: https://syzkaller.appspot.com/x/log.txt?x=10aa93d4580000 > kernel config: https://syzkaller.appspot.com/x/.config?x=c1ce97baf6bd6397 > dashboard link: https://syzkaller.appspot.com/bug?extid=169412e85b1803dfda81 > syz repro: https://syzkaller.appspot.com/x/repro.syz?x=10ed648c580000 #syz test --- a/kernel/smp.c +++ b/kernel/smp.c @@ -802,7 +802,6 @@ static void smp_call_function_many_cond( /* Check if we need remote execution, i.e., any CPU excluding this one. */ if (cpumask_any_and_but(mask, cpu_online_mask, this_cpu) < nr_cpu_ids) { - run_remote = true; cfd = this_cpu_ptr(&cfd_data); cpumask_and(cfd->cpumask, mask, cpu_online_mask); __cpumask_clear_cpu(this_cpu, cfd->cpumask); @@ -816,6 +815,7 @@ static void smp_call_function_many_cond( continue; } + run_remote = true; csd_lock(csd); if (wait) csd->node.u_flags |= CSD_TYPE_SYNC; @@ -843,8 +843,6 @@ static void smp_call_function_many_cond( send_call_function_single_ipi(last_cpu); else if (likely(nr_cpus > 1)) send_call_function_ipi_mask(cfd->cpumask_ipi); - else - run_remote = false; } /* Check if we need local execution. */ --