From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1793831739; b=tKoIgmcp34HspCe8diao2kfACjX5jGrAyLhwWfCSGs+hwiH8MCgXDdGg9tQlnop1CM9o D/Rt1zldqQ9SRqWAA6Ou2QHmUOVoh0bhlZ0Y5mwVIizOVSeUfHzbYJbamoonU3wRnqJD1 vtehML6NvNqGVm3niy701FA7kzEkpSnJQLdwdGNh3P2W+Cs+I4QqIAvrcMPXyzVPOKzaO 8ol4kmNmEOOr/yeXZHYPlUS3rjdVNEjSsuLvo/D3G8+9w4fC8L+sA/ulTFuv/dAlbYwwb TSBItNdxF2THPKBrzuxhY8f/i59gg8LSVEAIixNjpfZ1535EjPaXy4Ha/HTrwygV5sg== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793831739; h=Received:DKIM-Signature:From:To:Cc:Subject:Date:Message-ID:X-Mailer: In-Reply-To:References:User-Agent:X-stable:X-Patchwork-Hint: MIME-Version:Content-Transfer-Encoding; bh=zVlWQYbaBpPp5IEWgycOy9OqkaPQNxOn2JVmc/F0KhY=; b=CZSEggnRsKUrCL9ckzoVSTQIBdS1Y2yQSIbaevXV70blUAGnLHPR4/C4KF02USl3lYlZ zjpmsehU+DnDzmuN/j/lAj5lLb4aMMSSzUDMsd2KSn7eKDviRTRrH7UHNTkGmML4qMdqP missWbivQGhvjVFE63xdRZu5UTsh6dDq1E9VUSDu3uUV60UXEcO23JD8eNhHCVPk/3PdW E33xI4tegGmArEwlLTvOE/Okb3aVHRyN5JqP9hdrNGyrSBXMoJDTwHt76mGWbolc2VZBL wg8N1fhweeZmHPnPSqI6QMJdPKAe3aX3GanvXDZG7IgGTCZfTRkq/QL5gRm46mBQ9AQ== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=2nJxSdn4; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 53D8B606A32F; Wed, 4 Nov 2026 22:35:39 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key, unprotected) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=2nJxSdn4 Received: by smtp.kernel.org (Postfix) with ESMTPSA id E52D31F000C1; Wed, 4 Nov 2026 22:35:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1793831739; bh=zVlWQYbaBpPp5IEWgycOy9OqkaPQNxOn2JVmc/F0KhY=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=2nJxSdn42YyrULDtZ6c/EiH7UoKuqJgWm/0RcIwpQJh0iEmEnluF0nXCMdNrfUCEM uZNqcb3F0wF8ZwptSMLdTS66V73D+KlW0GVX6iQm2ocI63vaYcnWGop71lZwL1gJGo C4T4m9TBAdircxwcHKa7m4OzglC/EzQovwDifGnM= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Mike Snitzer , Anna Schumaker Subject: [PATCH 6.18 0883/1005] NFS/localio: fix nfs_local_dio_misaligned tracepoint Date: Wed, 4 Nov 2026 16:10:16 -0500 Message-ID: <20261104211107.972099702@linuxfoundation.org> X-Mailer: git-send-email 2.56.0 In-Reply-To: <20261104211043.516122098@linuxfoundation.org> References: <20261104211043.516122098@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore X-Mailing-List: patches@lists.linux.dev List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Mike Snitzer commit 1ea352a0db8bcb6ff6820e9a8715aac0aa3c761f upstream. The intended focus of nfs_local_iters_setup_dio()'s call to trace_nfs_local_dio_misaligned() is on the middle segment being misaligned, yet the @offset passed in was local_dio->start_len. It would appear this was a cut-n-paste bug from the preceding nfs_local_iter_setup() call that passes local_dio->start_len. Fix this by passing the @offset as local_dio->middle_offset and calculate the start segment's offset rather than assume. Example traces, before this fix: python3-32744 [006] .l... 132946.352360: nfs_local_dio_write: fileid=00:33:1286 fhandle=0xf1f7c10b offset=1048759 count=1048576 mem_align=4 offset_align=512 start=1048759+329 middle=1049088+1048064 end=2097152+183 python3-32744 [006] .l... 132946.352360: nfs_local_dio_misaligned: fileid=00:33:1286 fhandle=0xf1f7c10b offset=329 count=1048064 mem_align=4 offset_align=512 start=329+329 middle=1049088+1048064 end=2097152+183 After this fix: python3-32744 [006] .l... 132946.352360: nfs_local_dio_write: fileid=00:33:1286 fhandle=0xf1f7c10b offset=1048759 count=1048576 mem_align=4 offset_align=512 start=1048759+329 middle=1049088+1048064 end=2097152+183 python3-32744 [006] .l... 132946.352360: nfs_local_dio_misaligned: fileid=00:33:1286 fhandle=0xf1f7c10b offset=1049088 count=1048064 mem_align=4 offset_align=512 start=1048759+329 middle=1049088+1048064 end=2097152+183 Fixes: 6a218b9c3183e ("nfs/localio: do not issue misaligned DIO out-of-order") Cc: stable@vger.kernel.org Signed-off-by: Mike Snitzer Signed-off-by: Anna Schumaker Signed-off-by: Greg Kroah-Hartman --- fs/nfs/localio.c | 2 +- fs/nfs/nfstrace.h | 5 ++++- 2 files changed, 5 insertions(+), 2 deletions(-) --- a/fs/nfs/localio.c +++ b/fs/nfs/localio.c @@ -448,7 +448,7 @@ nfs_local_iters_setup_dio(struct nfs_loc if (unlikely(!iocb->iter_is_dio_aligned[n_iters])) { trace_nfs_local_dio_misaligned(iocb->hdr->inode, - local_dio->start_len, local_dio->middle_len, local_dio); + local_dio->middle_offset, local_dio->middle_len, local_dio); return 0; /* no DIO-aligned IO possible */ } iocb->end_iter_index = n_iters; --- a/fs/nfs/nfstrace.h +++ b/fs/nfs/nfstrace.h @@ -1771,7 +1771,10 @@ DECLARE_EVENT_CLASS(nfs_local_dio_class, __entry->count = count; __entry->mem_align = local_dio->mem_align; __entry->offset_align = local_dio->offset_align; - __entry->start = offset; + if (local_dio->start_len) + __entry->start = local_dio->middle_offset - local_dio->start_len; + else + __entry->start = 0; __entry->start_len = local_dio->start_len; __entry->middle = local_dio->middle_offset; __entry->middle_len = local_dio->middle_len;