From mboxrd@z Thu Jan 1 00:00:00 1970 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.subspace.kernel.org (Postfix) with ESMTPS id 749B62ECD14; Wed, 19 Nov 2025 05:51:00 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=198.137.202.133 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1763531462; cv=none; b=Q4J/GotFgE1BoIvH0xbmtDqCeY5jRgsm2RqEGmLEqj/MNlikFn1xblnLdMBGZA8TPztZExLL3VwCqvAQU7mdT51Jv0KThv1XVP3y7oYqvohIJHIwCg/tk088oGQMn3lu9UvI+1PFiK6e0ptZ+xZaBlfaY16JEqkfkebPmcWwjDw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1763531462; c=relaxed/simple; bh=zO8zOpKaiSIXJHk0EPgcQ227CLXzPZYpyzntHJwRjdc=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=ebJ2+rqQSZbyVPmScXGnxHIQIgPPz54X0KOsjmlkUtECS20t6/u0Db/RZWucJ8mqjCYgcaqBb6dMJ4go6S1S/Mvxm9IMu3lhT75TOXm75+W5FE5mMfWWKxf+M4pgQrhmonFaAhIPHdGEHssAk2wq9JSIQDBGto5q6jCGhsCzzuE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=infradead.org; spf=none smtp.mailfrom=bombadil.srs.infradead.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b=Gl1NeohW; arc=none smtp.client-ip=198.137.202.133 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=infradead.org Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=bombadil.srs.infradead.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="Gl1NeohW" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20210309; h=In-Reply-To:Content-Type:MIME-Version :References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=oSUCW2aTXazbvbtd8t7tT7TQJ2omNwxbKL/AucooRco=; b=Gl1NeohWW4D63QJy037NIx5AwG 0hK0i3ORimeuhGTfy4ed0DNW3HMXWUDMF9+ZtXM6c3JgtTbWP4TzcT7yfS3Jdru/LulygCgwo9jOb MK8+YlbPb6aCLDH269juL/NLJJUPQ+LvPLV1fPDZvftwQ+YSQJ2WqnG0sQqQUqsYb7XQoLgO2UmHG nOl9BEtF/T8Xx+M+E+vnEbw+aD5QzBGs2v0+HNJT4P7BLAbSEqXFxvyM0ckeVaZedGV5irsLEkycD tJBKEhTWOUPiM6pE1MuNBha9J5v7mjdcyemLxC9o1TWST/i1IGn10uxmGvZ8MYINZVW9h4zPO/81a 0n9JbTtQ==; Received: from hch by bombadil.infradead.org with local (Exim 4.98.2 #2 (Red Hat Linux)) id 1vLb5k-00000002RCL-2l21; Wed, 19 Nov 2025 05:50:56 +0000 Date: Tue, 18 Nov 2025 21:50:56 -0800 From: Christoph Hellwig To: Andrii Nakryiko Cc: Matthew Wilcox , Linus Torvalds , Christoph Hellwig , "Darrick J. Wong" , SHAURYA RANE , akpm@linux-foundation.org, shakeel.butt@linux.dev, eddyz87@gmail.com, andrii@kernel.org, ast@kernel.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, linux-kernel-mentees@lists.linux.dev, skhan@linuxfoundation.org, david.hunter.linux@gmail.com, khalid@kernel.org, syzbot+09b7d050e4806540153d@syzkaller.appspotmail.com, bpf Subject: Re: [PATCH] mm/filemap: fix NULL pointer dereference in do_read_cache_folio() Message-ID: References: <20251114193729.251892-1-ssranevjti@gmail.com> <20251117164155.GB196362@frogsfrogsfrogs> Precedence: bulk X-Mailing-List: linux-fsdevel@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: X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html On Tue, Nov 18, 2025 at 11:27:47AM -0800, Andrii Nakryiko wrote: > Then please help make it better, give us interfaces you think are > appropriate. People do use this functionality in production, it's > important and we are not going to drop it. In non-sleepable mode it's > best-effort, if the requested part of the file is paged in, we'll > successfully read data (such as ELF's build ID), and if not, we'll > report that to the BPF program as -EFAULT. In sleepable mode, we'll > wait for that part of the file to be paged in before proceeding. > PROCMAP_QUERY ioctl() is always in sleepable mode, so it will wait for > file data to be read. That's pretty demanding: "If you don't give me the interface that I want I'll just poke into internals and do broken shit" isn't really the best way to make friends and win influence., > If you don't like the implementation, please help improve it, don't > just request dropping it "because BPF folks" or anything like that. Again, you're trying to put a lot of work you should have done on others. Everyone here is pretty helpful guiding when asking for help, but being asked at gunpoint to cleanup the mess your created is not going to get everyone drop their work and jump onto your project.