From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from lists.sourceforge.net (lists.sourceforge.net [216.105.38.7]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 030ACC77B7A for ; Wed, 24 May 2023 22:23:36 +0000 (UTC) Received: from [127.0.0.1] (helo=sfs-ml-2.v29.lw.sourceforge.com) by sfs-ml-2.v29.lw.sourceforge.com with esmtp (Exim 4.95) (envelope-from ) id 1q1wtK-0001ux-GR; Wed, 24 May 2023 22:23:34 +0000 Received: from [172.30.20.202] (helo=mx.sourceforge.net) by sfs-ml-2.v29.lw.sourceforge.com with esmtps (TLS1.2) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.95) (envelope-from ) id 1q1wtG-0001um-20 for linux-f2fs-devel@lists.sourceforge.net; Wed, 24 May 2023 22:23:30 +0000 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=sourceforge.net; s=x; h=Sender:In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=6a4TWuzTGi7+tMMLrCXx2xS2HLm+fpIBXBWX9SQFhJc=; b=hKwIs7tGVeu2cdD2hkbIE6bgp3 7xmC5BHkaCgM5KS5uEU5FkAfnNAadZxuzLy5AJ/n9RjLaZ9g2btSqaCcA9MyBeWsfflf2xx7qQ8Yt JLcjp9okjEpZig1suWMuxxQIJw7lCSHaPXy9KDLGNM/yA6JMeTwFSZPzPZC8Z9E46e9E=; DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=sf.net; s=x ; h=Sender:In-Reply-To:Content-Type:MIME-Version:References:Message-ID: Subject:Cc:To:From:Date:Reply-To:Content-Transfer-Encoding:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:List-Id:List-Help:List-Unsubscribe:List-Subscribe: List-Post:List-Owner:List-Archive; bh=6a4TWuzTGi7+tMMLrCXx2xS2HLm+fpIBXBWX9SQFhJc=; b=H0GTAsYrSANQmJYVbbKhYAlVnG PZYZq19GzLdMfzPtAD24RJn3xzCgJxPntq4jPyuvHARrAs7pXQkx+E9iglS5pqc3mbNpy/tFTmhjX bUkuL1sDUoELTfaR1FO6x2abDu6zY40jcQxxX+l+B7tweVw4m3abPE8eVcKAFTGayogI=; Received: from bombadil.infradead.org ([198.137.202.133]) by sfi-mx-1.v28.lw.sourceforge.com with esmtps (TLS1.2:ECDHE-RSA-AES256-GCM-SHA384:256) (Exim 4.95) id 1q1wtC-001imR-OS for linux-f2fs-devel@lists.sourceforge.net; Wed, 24 May 2023 22:23:30 +0000 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20210309; h=Sender:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=6a4TWuzTGi7+tMMLrCXx2xS2HLm+fpIBXBWX9SQFhJc=; b=Olg5NsAiR4MXUKxEfN0JWQ26G+ 48QUUb0p3dP2AO5RET1yB+OlmxpPgfW/OAuL8L3TmcLxGehBJ8zrOmr2kBjQvXnIDe74EGIXQUw5V jrolzbG8yKU05ZkW5mpKw/LmaGIzjIW2osv7EnQcuMT1PVUpROY1wInr2AXsx/P1CtXqq68pLnhwc o//oJNGyzcS02XIm8oZ0EkYqFxmeJvu+ZYfriDV2Rx6DKfxLwq6Z2WZASZL/SOiLmZyzD7t1ZY8rR AcKIKrMHyGez7UPTrzHiDlh7DZpdMV2McGOt3pus8tAT+JlDrTHSf6mbJJPR2Ulm/XYS7au9Vkv2O 3mANUUxw==; Received: from mcgrof by bombadil.infradead.org with local (Exim 4.96 #2 (Red Hat Linux)) id 1q1wsv-00EnXL-1n; Wed, 24 May 2023 22:23:09 +0000 Date: Wed, 24 May 2023 15:23:09 -0700 From: Luis Chamberlain To: Christoph Hellwig , Daniel Gomez , Pankaj Raghav , Ming Lei Message-ID: References: <20230424054926.26927-1-hch@lst.de> <20230424054926.26927-15-hch@lst.de> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20230424054926.26927-15-hch@lst.de> X-Headers-End: 1q1wtC-001imR-OS Subject: Re: [f2fs-dev] [PATCH 14/17] block: open code __generic_file_write_iter for blkdev writes X-BeenThere: linux-f2fs-devel@lists.sourceforge.net X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Jens Axboe , linux-block@vger.kernel.org, linux-nfs@vger.kernel.org, cluster-devel@redhat.com, linux-xfs@vger.kernel.org, Miklos Szeredi , "Darrick J. Wong" , linux-kernel@vger.kernel.org, Matthew Wilcox , linux-f2fs-devel@lists.sourceforge.net, David Howells , linux-mm@kvack.org, linux-fsdevel@vger.kernel.org, Andrew Morton , linux-ext4@vger.kernel.org, ceph-devel@vger.kernel.org Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: linux-f2fs-devel-bounces@lists.sourceforge.net On Mon, Apr 24, 2023 at 07:49:23AM +0200, Christoph Hellwig wrote: > Open code __generic_file_write_iter to remove the indirect call into > ->direct_IO and to prepare using the iomap based write code. > > Signed-off-by: Christoph Hellwig > --- > block/fops.c | 46 ++++++++++++++++++++++++++++++++++++++++++++-- > 1 file changed, 44 insertions(+), 2 deletions(-) > > diff --git a/block/fops.c b/block/fops.c > index b670aa7c5bb745..fd510b6142bd57 100644 > --- a/block/fops.c > +++ b/block/fops.c > @@ -508,6 +508,29 @@ static int blkdev_close(struct inode *inode, struct file *filp) > return 0; > } > > +static ssize_t > +blkdev_direct_write(struct kiocb *iocb, struct iov_iter *from) > +{ > + size_t count = iov_iter_count(from); > + ssize_t written; > + > + written = kiocb_invalidate_pages(iocb, count); > + if (written) { > + if (written == -EBUSY) > + return 0; > + return written; > + } > + > + written = blkdev_direct_IO(iocb, from); > + if (written > 0) { > + kiocb_invalidate_post_write(iocb, count); > + iocb->ki_pos += written; > + } Written can be negative here after blkdev_direct_IO() > + if (written != -EIOCBQUEUED) > + iov_iter_revert(from, count - written - iov_iter_count(from)); And we'll then use it here on iov_iter_revert() and this can crash on with some values. For example this can crash on a 4k write attempt on a 32k drive when experimenting wit large block sizes. kernel BUG at lib/iov_iter.c:999! invalid opcode: 0000 [#1] PREEMPT SMP PTI CPU: 4 PID: 949 Comm: fio Not tainted 6.3.0-large-block-20230426-dirty#28 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.0-debian-1.16.0-5 04/01/2014 +RIP: 0010:iov_iter_revert.part.0+0x16e/0x170 Code: f9 40 a2 63 af 74 07 03 56 08 89 d8 29 d0 89 45 08 44 89 6d 20 RSP: 0018:ffffaa52006cfc60 EFLAGS: 00010246 RAX: 0000000000000016 RBX: 0000000000000016 RCX: 0000000000000000 RDX: 0000000000000004 RSI: 0000000000000006 RDI: ffffaa52006cfd08 RBP: ffffaa52006cfd08 R08: 0000000000000000 R09: ffffaa52006cfb40 R10: 0000000000000003 R11: ffffffffafcc21e8 R12: 0000000000004000 R13: 0000000000003fea R14: ffff9de3d7565e00 R15: ffff9de3c1f68600 FS: 00007f8bfe726c40(0000) GS:ffff9de43bd00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f8bf5eadd68 CR3: 0000000102c76001 CR4: 0000000000770ee0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 PKRU: 55555554 Call Trace: blkdev_direct_write+0xf0/0x160 blkdev_write_iter+0x11b/0x230 io_write+0x10c/0x420 ? kmem_cache_alloc_bulk+0x2a1/0x410 ? fget+0x79/0xb0 io_issue_sqe+0x60/0x3b0 ? io_prep_rw+0x5a/0x190 io_submit_sqes+0x1e6/0x640 __do_sys_io_uring_enter+0x54c/0xb90 ? handle_mm_fault+0x9a/0x340 ? preempt_count_add+0x47/0xa0 ? up_read+0x37/0x70 ? do_user_addr_fault+0x27c/0x780 do_syscall_64+0x37/0x90 entry_SYSCALL_64_after_hw Although I fixed it with an early check on this routine with: if (count < bdev_logical_block_size(bdev)) return -EINVAL; I think this can just be fixed by also using the alignment check earier here: if (blkdev_dio_unaligned(bdev, pos, iter)) return -EINVAL; Luis _______________________________________________ Linux-f2fs-devel mailing list Linux-f2fs-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel