From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out-185.mta0.migadu.com (out-185.mta0.migadu.com [91.218.175.185]) (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 9C37C4A01 for ; Sat, 22 Feb 2025 00:48:59 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=91.218.175.185 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1740185342; cv=none; b=bqac0Cg/auQywjSE/CJusC1bQxuxB82AySLTdvICx6mbPuF9vfZPEHbOOiFY1bam/h0anNdJKJG58uHbT5RZqsTijM4uq8D72z0OmRP2+3Y4eDIqfHKBiSqfS6SqlXGw96gXQncDpOFf0Oy7bedW0fcJERvL6Rb4QeAPmno9deo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1740185342; c=relaxed/simple; bh=0MWV2m0La6Zk3eE/f8ukJR9um6xaHgGpoIBCI9DjuTg=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=huoAB/HgC4Mrr92Cn0yiIa6LTmEXofxdAVxUJkT99rgomN+3R/XfYI6kXK3GNYkzVnLwq4M9m4arkwPFifKLsBbYPq/OdhDNLAdysoCEhPs4X/TnHgifNnx7Z7nGyZiWlgYj2O40qPEKON244mrJAbFThZdXT6pgXDLdlVWBnV4= 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=EKpE9QCu; arc=none smtp.client-ip=91.218.175.185 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="EKpE9QCu" Date: Sat, 22 Feb 2025 00:48:51 +0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1740185337; 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=p4Zst46Y7pj1nzoh7gV1XNEH5xnb01/ZQglbBvg9mw0=; b=EKpE9QCuth3FK6o61yyUqeyKAPhA00/7ADQUR9v8193RzSpKlzdjxgWPUfacvo7zElF8oM nvUPPeCgOoacI43Lg9vpl+g0kSx8+zijAmxLgqDfsctdKKhS3z8oA5xcDKTiJfvJ4uTXQt kYpMMq4H4+5bItmteexJDETFIJnrOS0= X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. From: Yosry Ahmed To: Ira Weiny Cc: syzbot , Barry Song <21cnbao@gmail.com>, akpm@linux-foundation.org, chengming.zhou@linux.dev, hannes@cmpxchg.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, nphamcs@gmail.com, syzkaller-bugs@googlegroups.com Subject: Re: [syzbot] [mm?] kernel BUG in sg_init_one Message-ID: References: <20240318204212.36505-1-21cnbao@gmail.com> <0000000000009221d60613f58726@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=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: X-Migadu-Flow: FLOW_OUT On Wed, Feb 12, 2025 at 09:20:24AM -0800, Yosry Ahmed wrote: > On Mon, Mar 18, 2024 at 2:03 PM Barry Song <21cnbao@gmail.com> wrote: > > > > On Tue, Mar 19, 2024 at 9:52 AM syzbot > > wrote: > > > > > > Hello, > > > > > > syzbot has tested the proposed patch but the reproducer is still triggering an issue: > > > WARNING in __kmap_to_page > > > > > > ------------[ cut here ]------------ > > > WARNING: CPU: 0 PID: 3529 at mm/highmem.c:167 __kmap_to_page+0x100/0x194 mm/highmem.c:167 > > > Modules linked in: > > > > + Ira > > > > Hi Ira, > > > > I noticed this warning is coming from commit ef6e06b2ef87077. > > > > you have a commit message like > > " Because it is intended to remove kmap_to_page() add a warn on once to > > the kmap checks to flag potential issues early. > > " > > > > Do we have a replacement for kmap_to_page()? The background is that we > > want to pass a highmem buffer to sg_set_page() but we only know its virt > > address. > > I am reviving this thread because new zsmalloc changes will make > mappings sleepable, which will allow zswap to drop the memcpy() in > zswap_decompress() -- except for the !virt_addr_valid() case. We can > get rid of that too if we can use kmap_tp_page() in the scatterlist > code. > > Ira, could you please answer Barry's question above about > kmap_to_page()? It has been a year and kmap_to_page() is still around. (Trying again with Ira as the main recepient just in case) Ira, could you please help us out here? :) > > Thanks.