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 E41CDC4452B for ; Tue, 21 Jul 2026 18:30:59 +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-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:Cc:To:In-Reply-To:References:Date: Message-Id:From:Subject:MIME-Version:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=cOOueQK+lXVjfLzXzrQlNBj6H7NBphnnt3gmn/nri7w=; b=KhzkovfX/xt1wc RH+mkdNjI22clV55bf26JJJigWu3umLuoIgoUzlCIJnqTyLx2C3ue159s3yozYPRNHVBFKm/D+8rb PaimlLdc3bYVeWxPTKcosXyYIVtKU/GarJRo4/lQX437Ka/X2qoRLf6hTgSGrbnv6s+0fEvRWEo3f gttOezjNFFgu26MXUwP48VAHMeNR9QZwbesNJBc1SPHtROUmlQPNtzZRmOhAdMv875N0dsUzJRx0J BInUiL1nlhGeSSu6PpMnw+IzLV8Bi0zW3aypHY69w/rNEZAVbB3VMxMRsGyvh3BNAl/iMDbIyQbsf EHfQ/4cteDZHCe+cPrlQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1wmFEw-0000000ADDL-1Uok; Tue, 21 Jul 2026 18:30:50 +0000 Received: from sea.source.kernel.org ([2600:3c0a:e001:78e:0:1991:8:25]) by bombadil.infradead.org with esmtps (Exim 4.99.1 #2 (Red Hat Linux)) id 1wmFEu-0000000ADCX-442C for linux-riscv@lists.infradead.org; Tue, 21 Jul 2026 18:30:49 +0000 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by sea.source.kernel.org (Postfix) with ESMTP id B59924174A; Tue, 21 Jul 2026 18:30:48 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 925F61F00A3A; Tue, 21 Jul 2026 18:30:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1784658648; bh=xImigRmDnIx1zusSwHpXh3TKLKehrpgm2XReoQ8B3p4=; h=Subject:From:Date:References:In-Reply-To:To:Cc; b=aRAP1m8nSJHiWjBmQgmhAPrtgBI6FDHCA1EWKJaAtrnW3PPTEiluupniJbTDpo6Xm tpkIjaYc0uD4DRsdhr8a3GoUmHNpxoJHkeL2N4RkUb/yAaVGYU0dfX6SpOX2kgB6/K loc35dANYletc4bdaq6mDfajSfkxdDTWFaLo4EE5OjF8FeOjn3wuWLCFGUWZ9JqGjD AhLd+JGE3rZkAHlKY9ilU+iAF+UPEUrLWFJxUHTTZbOLVXrmOStVDQRJVTVuUAHkv3 mrYMGZdPUdB/ceqcNtvNL0f0wJBiU0/yiVvLE63bas1DgcAJsAR2VdVqbJSj/wK96L M/LhQzZvVMO3g== Received: from [10.30.226.235] (localhost [IPv6:::1]) by aws-us-west-2-korg-oddjob-rhel9-1.codeaurora.org (Postfix) with ESMTP id 56B0F39253EE; Tue, 21 Jul 2026 18:30:19 +0000 (UTC) MIME-Version: 1.0 Subject: Re: [PATCH bpf-next v6 0/7] Mixing bpf2bpf and tailcalls for RV64 From: patchwork-bot+netdevbpf@kernel.org Message-Id: <178465861815.931197.16356281577887013283.git-patchwork-notify@kernel.org> Date: Tue, 21 Jul 2026 18:30:18 +0000 References: <20260708064436.2971933-1-pulehui@huaweicloud.com> In-Reply-To: <20260708064436.2971933-1-pulehui@huaweicloud.com> To: Pu Lehui Cc: bpf@vger.kernel.org, linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org, bjorn@kernel.org, ast@kernel.org, daniel@iogearbox.net, andrii@kernel.org, eddyz87@gmail.com, martin.lau@linux.dev, song@kernel.org, yonghong.song@linux.dev, john.fastabend@gmail.com, kpsingh@kernel.org, sdf@fomichev.me, haoluo@google.com, jolsa@kernel.org, puranjay@kernel.org, pjw@kernel.org, palmer@dabbelt.com, alex@ghiti.fr, pulehui@huawei.com 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: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-riscv" Errors-To: linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org Hello: This series was applied to bpf/bpf-next.git (master) by Kumar Kartikeya Dwivedi : On Wed, 8 Jul 2026 06:44:29 +0000 you wrote: > In the current RV64 JIT, if we just don't initialize the TCC in subprog, > the TCC can be propagated from the parent process to the subprocess, but > the updated TCC of the parent process cannot be restored when the > subprocess exits. Since the RV64 TCC is initialized before saving the > callee saved registers into the stack, we cannot use the callee saved > register to pass the TCC, otherwise the original value of the callee > saved register will be destroyed. So we implemented mixing bpf2bpf and > tailcalls similar to x86_64, i.e. using a non-callee saved register to > transfer the TCC between functions, and saving that register to the > stack to protect the TCC value. As for the tailcall hierarchy issue, > inspired by the s390's low-overhead approach, we store TCC from > RV_REG_TCC back to stack after calling bpf2bpf call or calling orig bpf > func in bpf trampoline. > > [...] Here is the summary with links: - [bpf-next,v6,1/7] bpf: Extract the is_struct_ops_tramp helper https://git.kernel.org/bpf/bpf-next/c/6bcecae4b65d - [bpf-next,v6,2/7] riscv, bpf: Fix memory leak in bpf_jit_free https://git.kernel.org/bpf/bpf-next/c/369e4635d048 - [bpf-next,v6,3/7] riscv, bpf: Using kvzalloc_objs to allocate cache buffer https://git.kernel.org/bpf/bpf-next/c/f3ab878594b5 - [bpf-next,v6,4/7] riscv, bpf: Fix kernel stack corruption in tailcall with CFI https://git.kernel.org/bpf/bpf-next/c/52fb1756ea1d - [bpf-next,v6,5/7] riscv, bpf: Add RV_TAILCALL_OFFSET macro to format tailcall offset https://git.kernel.org/bpf/bpf-next/c/a21731f54cfe - [bpf-next,v6,6/7] riscv, bpf: Mixing bpf2bpf and tailcalls https://git.kernel.org/bpf/bpf-next/c/ec72848ca0ad - [bpf-next,v6,7/7] selftests/bpf: Remove tailcalls tests from DENYLIST.riscv64 https://git.kernel.org/bpf/bpf-next/c/683ed8b78c1d You are awesome, thank you! -- Deet-doot-dot, I am a bot. https://korg.docs.kernel.org/patchwork/pwbot.html _______________________________________________ linux-riscv mailing list linux-riscv@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-riscv