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 99DA213959D; Sun, 29 Mar 2026 00:20:43 +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=1774743643; cv=none; b=o7M7zGyBJY5LAIEtTBej3lJpS+Dte046jpJTYqonjafocXdsr0td8wbyKRwWnrbWX+zE8JBLuotQHx/E8XoHo2N5/pfCC4JGpNL2apj9OWTXuy+Wf0zIW6tDSVjXVcL9MX5cEBmahNSedar705LDkw7vEWASv+nGc8gMch8MkiY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774743643; c=relaxed/simple; bh=iBjcUas4szwLS8i0MrfSdHNF7sZCD3Sz7+3s4V9sygc=; h=Date:Message-ID:From:To:Cc:Subject:In-Reply-To:References; b=exu+4HzkoHJs19a9jZqWG/ro6zxTa9PV0Wl3eMYyuk40lB9k73HzbTae4e8+vDKGLbmVt5O233AgYYVwSimhHp5ahv8DZCPifCCnV8Tbqv7H7vxy923x2CZlpKkGrCfDsN+EZ/PDdi1pVPz8e5cGnbJ4OlOjru0uwNx/WeGbs6E= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=A+yco74Q; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="A+yco74Q" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0C20BC4CEF7; Sun, 29 Mar 2026 00:20:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1774743643; bh=iBjcUas4szwLS8i0MrfSdHNF7sZCD3Sz7+3s4V9sygc=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=A+yco74Q7BzpZYZwjOjsFZJYWfrK5y9N9jZfy3aInEgj6+H5rMW/BPCcCvGRrTMCW K2rrEb+WtOO8p0YTXH4qLb9UDvbAXwkmE2PP05OZMCUbomIPrfe7HWGm4BgbFYAXOI 8gwe3KKmGGCdP5kvjmmpLeDq4U5IcIOIEx8TOIcGajyOiKLNmKQNuWv1OcPmonncMb C9h/MrQhMtxQOkUlfJYrpRVEl8Xhe3u2TR7gicfn8MxOoyWKjNDUPiogjJwZ9igxHU teUUklngX0PipFLAxlk65ukGjl2M3OhZxY0hlqILMQKVzFQ0vR+6ej48ExII5jUQvI GRv024csBYmxw== Date: Sat, 28 Mar 2026 14:20:42 -1000 Message-ID: From: Tejun Heo To: Christian Loehle Cc: sched-ext@lists.linux.dev, linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org, void@manifault.com, arighi@nvidia.com, changwoo@igalia.com, mingo@redhat.com, peterz@infradead.org, shuah@kernel.org, dietmar.eggemann@arm.com, emil@etsalapatis.com Subject: Re: [PATCH 1/2] sched_ext: Prevent SCX_KICK_WAIT deadlock by serialization In-Reply-To: <20260316100249.1651641-1-christian.loehle@arm.com> References: <20260316100249.1651641-1-christian.loehle@arm.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Hello, I posted an alternative fix here: https://lore.kernel.org/r/20260329001856.835643-1-tj@kernel.org Instead of serializing the kicks, it defers the wait to a balance callback which can drop the rq lock and enable IRQs, avoiding the deadlock while preserving the concurrent kick_wait semantics. Thanks. -- tejun