From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 9EC21C77B7D for ; Mon, 15 May 2023 17:44:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:Content-Type: List-Subscribe:List-Help:List-Post:List-Archive:List-Unsubscribe:List-Id: In-Reply-To:MIME-Version:References:Message-ID:Subject:Cc:To:From:Date: Reply-To:Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date :Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=vFE782eAlals/kRtsS6lzmRnsDZPWMmSwLohHnYdU5E=; b=B5LIwZWC+uhItOOxc9BhICsVRk hmLwmUV36+GI0rv2XIXBExRWYVqkTcDvghiJF/WyAWXANDs4QqDpQJEpiphfn3y1MuLIQ4UxakC3N TOaJUAFaO53kZqcONwo+a650K4Bt7uJvRB94vjrvW+c6OILOd2xLVw/2/h9inLHjbPte0juBAzF5l 1exoFsrsHk7q7bWcIhgngrDyAcZiuZMs5fpylK+5eEg+nIwXBPzKA6qssHk4u3npyLfqHBgoZzHG/ f/kAejoPZD9PUL2iFMCebQIjEmMfGlob6UBYX06493W/FxcDGGYdYK6VCfrGUNP08lofRyckmfnli Hyg1zzTA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1pycEu-002zLZ-0n; Mon, 15 May 2023 17:44:04 +0000 Received: from dfw.source.kernel.org ([139.178.84.217]) by bombadil.infradead.org with esmtps (Exim 4.96 #2 (Red Hat Linux)) id 1pycEq-002zKX-3A for linux-riscv@lists.infradead.org; Mon, 15 May 2023 17:44:02 +0000 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 8E12462E95; Mon, 15 May 2023 17:44:00 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 74E2FC433EF; Mon, 15 May 2023 17:43:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1684172640; bh=InLf1Tw5b2pCZIBk6BFn6OWKVf3tBsDAE0r1X+/jVuU=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=KU27NtmcyFyg666SNMSpu3ZNzj9Ud6cj2E3hEkDRUkAagU0oF6YGS/JSW2ryK3kph 1t+KR+O1oDzm7qXJSsoNaidnk+qQky0Rl8MYlIpYJmLAQeU5S+h23xYnxX6N26nByz Z5c2EBTqSPLF/43UcRxAvj7fBUYkjkskDi4X0j9VK7ymWdQU8EHxEUPbyOTKIFWZM1 r4LyEN0XWK9L9OVf0fCUXeQukS8mWp446PAZBP86ntArriSp2cA7knFeMsM96uue0p VLzztvU4eWsNwISvij2mh2BdYTxq4HJDgjtSSYxTPY6GdCqMyVqRyHO0ASHpg0P2Al pao8fxw8NaNfw== Date: Mon, 15 May 2023 18:43:56 +0100 From: Conor Dooley To: Ze Gao Cc: Paul Walmsley , Palmer Dabbelt , Albert Ou , Ze Gao , linux-riscv@lists.infradead.org, bpf@vger.kernel.org Subject: Re: [PATCH 0/4] Make fpobe + rethook immune to recursion Message-ID: <20230515-dominion-botch-e0b9291bcea3@spud> References: <20230515031314.7836-1-zegao@tencent.com> MIME-Version: 1.0 In-Reply-To: <20230515031314.7836-1-zegao@tencent.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20230515_104401_058212_D2E148AC X-CRM114-Status: GOOD ( 13.74 ) X-BeenThere: linux-riscv@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: multipart/mixed; boundary="===============4856468197293613112==" Sender: "linux-riscv" Errors-To: linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org --===============4856468197293613112== Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="dqLazd8WcdDsY/XF" Content-Disposition: inline --dqLazd8WcdDsY/XF Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Mon, May 15, 2023 at 11:13:09AM +0800, Ze Gao wrote: > Current fprobe and rethook has some pitfalls and may introduce kernel sta= ck recusion, especially in > massive tracing scenario. >=20 > For example, if (DEBUG_PREEMPT | TRACE_PREEMPT_TOGGLE) , preempt_count_{a= dd, sub} can be traced via > ftrace, if we happens to use fprobe + rethook based on ftrace to hook on = those functions,=20 > recursion is introduced in functions like rethook_trampoline_handler and = leads to kernel crash > because of stack overflow. This patch series is a bit confusing. The RISC-V list got 2 cover letters and 2 patch 4s, but not any of the rest of the series. Please at least send the whole series to the list so our patchwork automation can be run against it. And mark it as v2 while you are at it. Thanks, Conor. --dqLazd8WcdDsY/XF Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iHUEABYIAB0WIQRh246EGq/8RLhDjO14tDGHoIJi0gUCZGJvWwAKCRB4tDGHoIJi 0j9VAQCg19aD+YHZwreeVgv/iHphWBuLDk8i96FhqjjGX2NOiwEA6/jsuqh1ILFe CqUFzOZWPPeZCLFUHSr939+zcR5isgs= =bf8c -----END PGP SIGNATURE----- --dqLazd8WcdDsY/XF-- --===============4856468197293613112== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ linux-riscv mailing list linux-riscv@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-riscv --===============4856468197293613112==--