From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) (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 01AEE306B02 for ; Fri, 16 Jan 2026 08:38:06 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.133.124 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768552688; cv=none; b=sgXe2cpoelYYMqMhRPBSfGnL7rfcAm50+8iSQfl0IX2Kck7lvdtg+kDlO8N31rDGnJL3w/YSdhkoVXenFrNAvE3lgbrCrcgkLow2qdln0iU7slEW4f8Qd5gX2Hc42DdWRKzxWDP7aDD3Wj6GvDtGTrSNO+ewxbP4sW/IQXd0R94= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768552688; c=relaxed/simple; bh=lvIHXFFHUhdKTg8BHp62azwSjGzwhVeI1ynv3yGuVy8=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=VR9SZ4gSbrvwxhLslVQy8PbxfynwC1DyHQAq+FC9qw2DTTfYYJqs85JyiyYpUhTXSAlBdRAjorzcThl4mE9Ymg9McvZJ2q/N1FN0X3aTubj5C8c8n6K+lID8mKWWVmBd1x/sMB7h+e9BKSoseNP9759kZEMghYp+7LKnWjalk+k= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=gmIecQrK; arc=none smtp.client-ip=170.10.133.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="gmIecQrK" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1768552685; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding; bh=gMnGjFts1uIsAxKxKvee17RL2ecdmw+veG5wHjh1ua8=; b=gmIecQrKPfN64xvaYAG24EBcq2WkVskB+hYcy+c4ITem41SGtl0qLr7lbbGVDZXX4bbqdf M4ViZntDGIbydkiqJI/BZtKo0Vcfc+kMMLBW9wosJqgaZQb8CJvMHPUdh3YWe4C8iX8O4/ 72AbnL0FKWm7OeSQKXYx2FzUdJtyqZc= Received: from mx-prod-mc-05.mail-002.prod.us-west-2.aws.redhat.com (ec2-54-186-198-63.us-west-2.compute.amazonaws.com [54.186.198.63]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-156-sIuva9ljOaaE1EVx9Tr7uQ-1; Fri, 16 Jan 2026 03:38:04 -0500 X-MC-Unique: sIuva9ljOaaE1EVx9Tr7uQ-1 X-Mimecast-MFC-AGG-ID: sIuva9ljOaaE1EVx9Tr7uQ_1768552683 Received: from mx-prod-int-01.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-01.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.4]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-05.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 7FE4B1956088 for ; Fri, 16 Jan 2026 08:38:03 +0000 (UTC) Received: from intrepid (unknown [10.43.3.0]) by mx-prod-int-01.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTP id E7CBA30002D6; Fri, 16 Jan 2026 08:38:01 +0000 (UTC) From: Attila Fazekas To: williams@redhat.com, jkacur@redhat.com, debarbos@redhat.com Cc: linux-rt-users@vger.kernel.org, Attila Fazekas Subject: [PATCH] [ssdd] add ptrace tierdown for the tests Date: Fri, 16 Jan 2026 03:37:36 -0500 Message-ID: <20260116083736.27032-1-afazekas@redhat.com> Precedence: bulk X-Mailing-List: linux-rt-users@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.4 Without tierdown the tracee can receive SIGTRAP leading to multiple core dumps being created. At higher concurrency you may also see coredump: 11747(ssdd): over core_pipe_limit, skipping core dump in the dmesg with kernel.core_pattern = |/usr/lib/systemd/systemd-coredump %P %u %g %s %t %c %h %d %F kernel.core_pipe_limit = 16 Signed-off-by: Attila Fazekas --- src/ssdd/ssdd.c | 18 ++++++++++++++++-- 1 file changed, 16 insertions(+), 2 deletions(-) diff --git a/src/ssdd/ssdd.c b/src/ssdd/ssdd.c index 63130cd..61aab84 100644 --- a/src/ssdd/ssdd.c +++ b/src/ssdd/ssdd.c @@ -312,9 +312,23 @@ static int forktests(int testid) got_sigchld = 0; } - /* There is no need for the tracer to kill the tracee. It will - * automatically exit when its owner, ie, us, exits. + /* The tracee can receive SIGTRAP(dump) without detaching. */ + pstatus = ptrace(PTRACE_DETACH, child, NULL, NULL); + if (pstatus == ~0l) { + printf("forktest#%d/%d: EXITING, ERROR: " + "detach failed. errno %d\n", + testid, getpid(), errno); + exit(1); + } + pstatus = kill(child, SIGKILL); + if (pstatus != 0) { + printf("forktest#%d/%d: EXITING, ERROR: " + "kill failed. errno %d\n", + testid, getpid(), errno); + exit(1); + } + if (!quiet) printf("forktest#%d/%d: EXITING, no error\n", testid, parent); exit(0); -- 2.52.0