From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pf1-f170.google.com (mail-pf1-f170.google.com [209.85.210.170]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 0E54D2BEC5E for ; Wed, 12 Nov 2025 18:38:35 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.210.170 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1762972717; cv=none; b=J3SU2nu6cgHroxcKi3Ns076kHG442X9xkX4GbeWp2fCXwqDcFZvJ30fkzI0kEbv6KYUVgJpdciTw1HDsioi2wvEeV+GeXxb93fsLnasooNS9cCtCJnfyBePsuaShJrCg+I6LW8Y61db3af0eHrG+tN1ojMIlQt0G06JplKdw+GQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1762972717; c=relaxed/simple; bh=rjdI/hPxB57OWIfqIRPggSIvkjgsaZxLZ95HFelCcGY=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=i8oXYz3g69zOIZZtXBTYpgvJsgUKVSW6Li4TysSRKdSPF38zESR50RZ1ldetrJ3XWURQk7aSfAU8YzMxQ9pEEDtkvS03beaTlEq+wSeMXnShwQGF/kn7WNgN/jLfdjaf4Dgj8xrUjvGplh9G6QepuaDpmQ1dKGgmPu4AnWh4pF8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=C1YP64lT; arc=none smtp.client-ip=209.85.210.170 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="C1YP64lT" Received: by mail-pf1-f170.google.com with SMTP id d2e1a72fcca58-7b4933bc4bbso1034651b3a.1 for ; Wed, 12 Nov 2025 10:38:35 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1762972715; x=1763577515; darn=vger.kernel.org; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:from:to:cc:subject:date:message-id:reply-to; bh=d+G8+iIuAhEgULEzocPDssGo8BH46zvY9bxVPTxi2Vs=; b=C1YP64lTmpPR3rpAi4nXm4pajuWzRnGOvB/NwB50yogSmfuta7NKCFyVQUPL1Apj8V mSr7bVW7YBn4Zbn0Zc4cMrEYNbKBouZfhtLRajLqWeSLcNH32SM3z1ccGl2UvNrcNV0H xu/WKO56sfn6ZosM2QScFhK3NURNDmW9S000t2z3hfooLzRZ48YC7Q9wtN8cLEJEM20v 4WmISrgEaSt6FUIgteIWyQy/PBOgrWCikXbwgvIvYPaxXGlEZWhEvjE0EeKuqdx3P5VK 7xJ25EGDBb6lk7dvv7uQds+Z68578wq3lrroPGnICn/nIh7oLn9/Zdy8srwUJRa87NYg lofg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1762972715; x=1763577515; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-gg:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=d+G8+iIuAhEgULEzocPDssGo8BH46zvY9bxVPTxi2Vs=; b=GLbztXHHt6l1C2FL55Dzk3ueBE+tC+1eNa6380xMCOSpNjrAdYpt0RCGEuNRYRH85T xtSYYC1XrR2itVf+dws3IicKl/QAg70BIIzwK1LoiMlghm0FUY8OLrm4e/L2YMKCW2/M 8JPjUdiPBmPAh5+BcNAQZ7aLh2iQ6OQ9ILyrAE+PcRtsFzAkaNrQKkQnpDxxk5lRYDqT OSo2Kkm/0jTQTqPuiLmPALMJ5mZQd0XAZj9biMyop5GnG79gPrhISfzfjnSNp9NjIlL/ bgE1efwbtNIdASDaUzxherDYeHjlMSf80kfyXzY75XNxY4pVTxIrVbSW3w39hoVtG5xY KLcg== X-Forwarded-Encrypted: i=1; AJvYcCU7QYmmAOELoOSGlDUB1R60zt1z1iBXO1dWh7AWTkBY5MjO9LiGQsmpJZgla+NOq3TNOg7Stzz2hjQ9qPM=@vger.kernel.org X-Gm-Message-State: AOJu0Yzh+qCnhH94/KjqwEvlCgRU4cZVhf/bRaH8kk+jaTfh+QN82cFx 9zkpgVGAQu0yCOe/iq90P/gYl7885eRINQQGSo/fLRlCKO0QRuaifBrX X-Gm-Gg: ASbGncueVTrSk+GKDv2ZghGwEC80F8EemQcHqa05thCl1y94SKsFHLWhp2bo5BzgV3W 6RqIt+9mukzKbWvjsmX1Mm114FuqQs8xIrTDxZ6VrjCDhK6J0qhAA2haxUDbY9GLecZWBG8bsoE lqSRFCqGvGijoBdnHHIrz8acdtzaD05+PzrFTple1rj8WkJFRyMkPjvJCy87q3zeZs2EAdQLSPX 1hUA5HU/KVpK88GJAEX7hqD2WJ3+R6/tfCdCI4Rn8IHHqGaQKEXKHcXAezvKv76cOXR29P2DhY9 jJ0bAyC/OfEwuKTL2641218KXqdeRiaCEu6bzPkrnRwaUT/xjfPgFtMP9sujfBVW3Br73+1V2En lfaPtTtGR1hvLA0sEFpZ+2rXTc+5llf1Vq/nMXeApk3/zfWdbZJKrAswERIFEBr+G+7/ciHHy8U 8lakE5UCJYBJEu+GyL4UTXtoswzVmUPRaL X-Google-Smtp-Source: AGHT+IHkCPrM3gjJlcuUw/ai+5zW7z604YwPQxNzYFX5718wDwKJoqe+bSM0awd32yJLRzmocpTJQg== X-Received: by 2002:aa7:88d6:0:b0:7a2:7f45:5898 with SMTP id d2e1a72fcca58-7b8e01e21a5mr455797b3a.3.1762972715085; Wed, 12 Nov 2025 10:38:35 -0800 (PST) Received: from fedora (c-67-164-59-41.hsd1.ca.comcast.net. [67.164.59.41]) by smtp.gmail.com with ESMTPSA id d2e1a72fcca58-7b0cc17a956sm19641876b3a.44.2025.11.12.10.38.34 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 12 Nov 2025 10:38:34 -0800 (PST) Date: Wed, 12 Nov 2025 10:38:32 -0800 From: "Vishal Moola (Oracle)" To: Uladzislau Rezki Cc: syzbot ci , akpm@linux-foundation.org, hch@lst.de, linux-kernel@vger.kernel.org, linux-mm@kvack.org, syzbot@lists.linux.dev, syzkaller-bugs@googlegroups.com Subject: Re: [syzbot ci] Re: make vmalloc gfp flags usage more apparent Message-ID: References: <20251110160457.61791-1-vishal.moola@gmail.com> <69123b72.a70a0220.22f260.0105.GAE@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: On Wed, Nov 12, 2025 at 01:02:03PM +0100, Uladzislau Rezki wrote: > On Tue, Nov 11, 2025 at 11:07:29PM -0800, Christoph Hellwig wrote: > > On Tue, Nov 11, 2025 at 09:21:06PM +0100, Uladzislau Rezki wrote: > > > > Unexpected gfp: 0x100000 (__GFP_HARDWALL). Fixing up to gfp: 0xdc0 (GFP_KERNEL|__GFP_ZERO). Fix your code! > > > > > > > It looks like we need to add __GFP_HARDWALL to the white-list-mask. > > > > __GFP_HARDWALL is part of GFP_USER. Doing GFP_USER vmalloc sounds like > > a bit of an odd idea to me, but there are a few users mostly in bpf > > and drm code (why do these always show up for odd API usage patterns?). > > > > So I guess yes, we'll need to allow it for now, but I'd like to start > > a discussion if it really makes much sense. > > > > /* plain bpf_prog allocation */ > prog = bpf_prog_alloc(bpf_prog_size(attr->insn_cnt), GFP_USER); > if (!prog) { > > > I assume that was the place that triggered the splat. > > Vishal, will you send the patch adding GFP_USER to address the splat? Yes, I'll send a new version including __GFP_HARDWALL in the mask and update the comment accordingly.