From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out-170.mta0.migadu.com (out-170.mta0.migadu.com [91.218.175.170]) (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 C54132931C6 for ; Fri, 17 Jul 2026 02:12:56 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=91.218.175.170 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784254378; cv=none; b=dSFo9VLCwGBxU1uSvD02XmpvdchmeAPtwnHdHaOlcVtLarrkny2VpveUmdb46Dexg1yRvFD5qqAl4AbnLU11QzU3j7bkyxfXPclipkcsV5RKYTfREQrsLVq0Rwv5lh6yNsqhdrBWWtrDgCgN6BlDdYeftQtI1YZdUhTeELlxmao= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784254378; c=relaxed/simple; bh=Ja0XyoAvhI3Xt3LRW6htgUJuKsQFPC/S2C0fYkpT+P0=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=PTLK1O1apLfeOh+hu4YBR7MuYHGDE8m7hrnUKmXibneSNiU92t8qxWpsgj6LquEpiC4bkboD4NwhN4ZCrl0QP0qCC35LuIMPPpDkiuK5KFdtKLs8jBPMSvIrt64rbvshiDzwDvHUVyiFgv+2UlpdI/YpacrOU1Xx4lnA2sBaIAE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b=OamFIAy4; arc=none smtp.client-ip=91.218.175.170 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b="OamFIAy4" Message-ID: DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1784254374; 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: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=CsTmuXwOvoneEY4iONWCqa5zdFZFDoCDBf0GmtOvujs=; b=OamFIAy4vAxqZPv3h2qcyKWoBSk6y8u5bJ9HAYOLC/mQpmJhmoRR27H31aGR8iDMYRo4G3 +sPaGlP1PWkazZ4kiQcVP8pmJS4TkqECGTeA6XNDVGKhhtDQgmvMJi4WCdreQ+1q74HUc6 QkQvn1de3+rRCj1IdG5pw8QaLJymj4o= Date: Fri, 17 Jul 2026 10:12:49 +0800 Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Subject: Re: PROBLEM: BPF interpreter fallback after JIT compilation of BPF_ADDR_PERCPU leads to kernel panic To: Vincent Thiberville , "ast@kernel.org" , "daniel@iogearbox.net" , Kumar Kartikeya Dwivedi , Eduard Zingerman Cc: "bpf@vger.kernel.org" References: <90c32de0-feac-4e63-9757-2a1d115be08c@linux.dev> Content-Language: en-US X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. From: Leon Hwang In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Migadu-Flow: FLOW_OUT On 16/7/26 19:27, Vincent Thiberville wrote: > On 1/7/26 04:49, Leon Hwang wrote: >> By changing 'r0 = 0' to nop, I can reproduce the BUG with bpf-next code: > [...] >> With this diff, the internal BPF_ADDR_PERCPU insn is supported in the interpreter. > > Thank you for the investigation and further details. > > Is a fix planned? This bug impacts stable versions of the kernel and is fairly > easy to trigger notably on Debian 13. With some ebpf programs, simply > enabling `bpf_jit_harden` on Debian 13 means a guaranteed kernel panic. The fix is on the way [1]. Once the fix gets applied, it should be backported to kernel 6.12 with prerequisite patch [2]. [1] https://lore.kernel.org/bpf/20260715141122.15783-4-leon.hwang@linux.dev/ [2] https://lore.kernel.org/bpf/20260708101806.18885-1-yangtiezhu@loongson.cn/ Thanks, Leon