From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-out.m-online.net (mail-out.m-online.net [212.18.0.10]) (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 11125191; Thu, 18 Dec 2025 14:53:03 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=212.18.0.10 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1766069587; cv=none; b=c+ct6bp8g7repHGCYCsYoQAOh9214AEcnxWV9x9iXJxwahykSO70x1Jsb7iSQOLVymV294ifjZjHZTP207YafrJfgLIIZO0xW9TmSnGCXWb6Ed2Noo+hmDGXURrlf6iWshxWtrR7/TG4C+JHTTC9eNIuBdcHjMTU3muNVgy28Fg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1766069587; c=relaxed/simple; bh=1tJPAzNE4seYqAInwkAAu2eJZnnIyziByoZ/2qLanGA=; h=From:To:Cc:Subject:In-Reply-To:References:Date:Message-ID: MIME-Version:Content-Type; b=ZemTH0I0Z1q+Xu8q73MMsTIOyr2RuSwayqDqUZ7X+vRvGjVgHE1JaXRH3dPQqORHiWa0TAbK/xe+VSqlwdlWQJf8TeFq2pvWjud1Tp+ilSchzQbop3qeTSSmeLjocuNHVu9Hp6EskYkU4Wfn96E3JmDA4zuCQRRUgaVYE44zTis= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=linux-m68k.org; spf=pass smtp.mailfrom=nefkom.net; arc=none smtp.client-ip=212.18.0.10 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=linux-m68k.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=nefkom.net Received: from mail-out.m-online.net (mail-out.m-online.net [212.18.0.10]) by mail-out.m-online.net (Postfix) with ESMTP id 4dXD4M2j9Mz1sFNS; Thu, 18 Dec 2025 15:45:55 +0100 (CET) Received: from frontend01.mail.m-online.net (unknown [192.168.8.182]) by mail-out.m-online.net (Postfix) with ESMTP id 4dXD4J3x1wz1sFNH; Thu, 18 Dec 2025 15:45:52 +0100 (CET) Received: from localhost (dynscan1.mnet-online.de [192.168.6.68]) by mail.m-online.net (Postfix) with ESMTP id 4dXD4J16fdz1qqlb; Thu, 18 Dec 2025 15:45:52 +0100 (CET) X-Virus-Scanned: amavis at mnet-online.de Received: from mail.mnet-online.de ([192.168.8.182]) by localhost (dynscan1.mail.m-online.net [192.168.6.68]) (amavis, port 10024) with ESMTP id l_Kr4_Abdg19; Thu, 18 Dec 2025 15:45:43 +0100 (CET) X-Auth-Info: f7NtxmpzHQmYe1l150J0FpcJ3IOvKgngAnPl/ySUigHkHQOe66PIM7oOIodZILzN Received: from igel.home (aftr-82-135-83-180.dynamic.mnet-online.de [82.135.83.180]) (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 mail.mnet-online.de (Postfix) with ESMTPSA; Thu, 18 Dec 2025 15:45:43 +0100 (CET) Received: by igel.home (Postfix, from userid 1000) id BFC012C1943; Thu, 18 Dec 2025 15:45:42 +0100 (CET) From: Andreas Schwab To: Menglong Dong Cc: ast@kernel.org, rostedt@goodmis.org, daniel@iogearbox.net, john.fastabend@gmail.com, andrii@kernel.org, martin.lau@linux.dev, eddyz87@gmail.com, song@kernel.org, yonghong.song@linux.dev, kpsingh@kernel.org, sdf@fomichev.me, haoluo@google.com, jolsa@kernel.org, mhiramat@kernel.org, mark.rutland@arm.com, mathieu.desnoyers@efficios.com, jiang.biao@linux.dev, bpf@vger.kernel.org, linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org, linux-riscv@lists.infradead.org Subject: Re: [PATCH bpf-next v3 3/6] bpf: fix the usage of BPF_TRAMP_F_SKIP_FRAME In-Reply-To: <20251118123639.688444-4-dongml2@chinatelecom.cn> (Menglong Dong's message of "Tue, 18 Nov 2025 20:36:31 +0800") References: <20251118123639.688444-1-dongml2@chinatelecom.cn> <20251118123639.688444-4-dongml2@chinatelecom.cn> Date: Thu, 18 Dec 2025 15:45:42 +0100 Message-ID: <874ipnkfvt.fsf@igel.home> User-Agent: Gnus/5.13 (Gnus v5.13) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain On Nov 18 2025, Menglong Dong wrote: > Some places calculate the origin_call by checking if > BPF_TRAMP_F_SKIP_FRAME is set. However, it should use > BPF_TRAMP_F_ORIG_STACK for this propose. Just fix them. > > Signed-off-by: Menglong Dong > Acked-by: Alexei Starovoitov This breaks RISC-V: [ 8.584381][ T1] systemd[1]: bpf-restrict-fs: LSM BPF program attached [ 8.588359][ T1] Insufficient stack space to handle exception! [ 8.588823][ T1] Task stack: [0xff20000000010000..0xff20000000014000] [ 8.589219][ T1] Overflow stack: [0xff600000ffdad070..0xff600000ffdae070] [ 8.590133][ T1] CPU: 1 UID: 0 PID: 1 Comm: systemd Not tainted 6.18.0-rc5+ #15 PREEMPT(voluntary) c900881ed1c1988ec5cf3e914d0edeb1b4d83ca3 [ 8.590898][ T1] Hardware name: riscv-virtio qemu/qemu, BIOS 2025.10 10/01/2025 [ 8.591494][ T1] epc : copy_from_kernel_nofault+0xa/0x198 [ 8.592292][ T1] ra : bpf_probe_read_kernel+0x20/0x60 [ 8.592658][ T1] epc : ffffffff802b732a ra : ffffffff801e6070 sp : ff2000000000ffe0 [ 8.593121][ T1] gp : ffffffff82262ed0 tp : 0000000000000000 t0 : ffffffff80022320 [ 8.593566][ T1] t1 : ffffffff801e6056 t2 : 0000000000000000 s0 : ff20000000010040 [ 8.593997][ T1] s1 : 0000000000000008 a0 : ff20000000010050 a1 : ff60000083b3d320 [ 8.594446][ T1] a2 : 0000000000000008 a3 : 0000000000000097 a4 : 0000000000000000 [ 8.594940][ T1] a5 : 0000000000000000 a6 : 0000000000000021 a7 : 0000000000000003 [ 8.595396][ T1] s2 : ff20000000010050 s3 : ff6000008459fc18 s4 : ff60000083b3d340 [ 8.595831][ T1] s5 : ff20000000010060 s6 : 0000000000000000 s7 : ff20000000013aa8 [ 8.596215][ T1] s8 : 0000000000000000 s9 : 0000000000008000 s10: 000000000058dcb0 [ 8.596641][ T1] s11: 000000000058dca7 t3 : 000000006925116d t4 : ff6000008090f026 [ 8.597065][ T1] t5 : 00007fff9b0cbaa8 t6 : 0000000000000016 [ 8.597363][ T1] status: 0000000200000120 badaddr: 0000000000000000 cause: 8000000000000005 [ 8.598033][ T1] Kernel panic - not syncing: Kernel stack overflow [ 8.598597][ T1] CPU: 1 UID: 0 PID: 1 Comm: systemd Not tainted 6.18.0-rc5+ #15 PREEMPT(voluntary) c900881ed1c1988ec5cf3e914d0edeb1b4d83ca3 [ 8.599244][ T1] Hardware name: riscv-virtio qemu/qemu, BIOS 2025.10 10/01/2025 [ 8.599659][ T1] Call Trace: [ 8.600117][ T1] [] dump_backtrace+0x28/0x38 [ 8.600517][ T1] [] show_stack+0x3a/0x50 [ 8.600844][ T1] [] dump_stack_lvl+0x56/0x80 [ 8.601176][ T1] [] dump_stack+0x18/0x22 [ 8.601518][ T1] [] vpanic+0xf6/0x328 [ 8.601819][ T1] [] panic+0x3e/0x40 [ 8.602088][ T1] [] handle_bad_stack+0x98/0xa0 [ 8.602395][ T1] [] bpf_probe_read_kernel+0x20/0x60 -- Andreas Schwab, schwab@linux-m68k.org GPG Key fingerprint = 7578 EB47 D4E5 4D69 2510 2552 DF73 E780 A9DA AEC1 "And now for something completely different."