From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from galois.linutronix.de (Galois.linutronix.de [193.142.43.55]) (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 55A4E2185A6; Mon, 11 Aug 2025 08:31:39 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=193.142.43.55 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1754901102; cv=none; b=Dd1rADFGCJuTQsIz6LnsmdUb/fp7P57a/6fDy2LWEX88cZdgAb/fPxwxe6J6tiTOT/hL/pTvK9wqD3zWzjXfLWEiTNLgMxbW2s2opQARfWOfhyDOxkUecV8B60zLx12KB2iZZwZzlbrFemzgXJqDUqFgIJnFH+0Qj7R+RLZdWf0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1754901102; c=relaxed/simple; bh=S4WuqofBa7Id6+qyAJHjdL5aqwr5DwpyzeUXtsy52u0=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=B56J2XZ+71Jx1uBpPSLWLHXIONVWpR5FwTZxOQLzaj6gMIFRu7JC3GUlS0QxAWYQgCif6OLbcsOKduMoq2HxPHYd2k44aFgtOuFnxMRp1jqvHstKoey80RJVmzmPi9rXA4VGBcOvEp4NqEVYWlg8QT1rfvlsRbu5SymgCqBVwIs= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linutronix.de; spf=pass smtp.mailfrom=linutronix.de; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=cZNO6N2q; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=lqsQIrkC; arc=none smtp.client-ip=193.142.43.55 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linutronix.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linutronix.de Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="cZNO6N2q"; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="lqsQIrkC" Date: Mon, 11 Aug 2025 10:31:35 +0200 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1754901096; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=JeEYEDHr31+P2zVZyryZ2NEbaRwQuOh+nfUwKPEWE1U=; b=cZNO6N2qunmSklZQNVYCQo5IIj9bIBmAgbV7ljn82yCgNMKRsvql6lShJ81ecxTLm3Cea8 s3Svi0EEJp2Z0Z1KNm6/DOaQwM74D5fo7OHtBHgOUewLhzgfVW7ElqxhU7QH2+rdFkTz0H 5/ogT5fYhQQgIjujBsmwXkk30pSWnTcsXE0qO0BbqPkrTRVIpPrK4xSgLlrMEx23lfuwnm t868ImjD2MHvJmsiQgOhLztDE14D6VZVKfntxVHLvu+MvTj9MckEanpgP5OuuHzuRT2a+9 Fk7Qo2knjuhMizdljcbbowfyNlMdH7i1H8LIZ9hMor2fYvRSgGtezMPKLvmRGA== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1754901096; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=JeEYEDHr31+P2zVZyryZ2NEbaRwQuOh+nfUwKPEWE1U=; b=lqsQIrkCdbT/b7o7yJ8/W5Y9Megw6NnMf5v16x2yzUciE9/VpFNPrhZstXL2XVYloQ5foV lc3jcWA8RlDD2IAA== From: Sebastian Andrzej Siewior To: Yunseong Kim Cc: Dmitry Vyukov , Andrey Konovalov , Byungchul Park , max.byungchul.park@gmail.com, Yeoreum Yun , Michelle Jin , linux-kernel@vger.kernel.org, Tetsuo Handa , Alan Stern , Greg Kroah-Hartman , Thomas Gleixner , stable@vger.kernel.org, kasan-dev@googlegroups.com, syzkaller@googlegroups.com, linux-usb@vger.kernel.org, linux-rt-devel@lists.linux.dev, Austin Kim Subject: Re: [PATCH] kcov, usb: Fix invalid context sleep in softirq path on PREEMPT_RT Message-ID: <20250811083135.xtl2wSQz@linutronix.de> References: <20250725201400.1078395-2-ysk@kzalloc.com> <20250808163345.PPfA_T3F@linutronix.de> Precedence: bulk X-Mailing-List: linux-usb@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: On 2025-08-09 02:35:48 [+0900], Yunseong Kim wrote: > Hi Sebastian, Hi Yunseong, > > Could someone maybe test this? > > As you requested, I have tested your patch on my setup. > > I can check that your patch resolves the issue. I have been running > the syzkaller for several hours, and the "sleeping function called > from invalid context" bug is no longer triggered. Thank you. I just sent this as a proper patch assuming kcov still does what it should. I just don't understand why this triggers after moving to workqueues and did not with the tasklet setup. Other that than workqueue code has a bit more overhead, it is the same thing. > I really impressed your "How to Not Break PREEMPT_RT" talk at LPC 22. Thank you. > > Tested-by: Yunseong Kim > > > Thanks, > > Yunseong Kim Sebastian