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=1793831728; b=mrQ/axkFScp3zFFeDzp1oFBUAz0h4WO3ZIQJf1oUjBxYboO2x5BLpWXWvKFDHhoRTfxl hsXhXAjxf2a/2EweshDIWqRhb8ciJO35vWcQSD3XUfhX5XR8X8sOzCekngQKG8gLAb5WC IgJy4OEuYAHlKtd+zs1vy6rwtFMznW22+IPvWSXhZ795ePd4ZHGkWZTfajydH36OFZbEm YKLjtuFYXlAMQEjUWKBbkMz+VZxXoOkqCEY3rSAX4Bg2EHIQWIFy0m6bjndxA+F+Dfhfq a8PFm/n0prW8azoVL4uvm4vJfbARr1Rhn3I3CutDI6/lQYnyPzzlNK3+UQv043JyQ/Q== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793831728; 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=MXdyztOkoUIF/MY4EG3Ev+5joYjKeRacNX9+s53tt+c=; b=j6sr9APa0WScWJRuruEqkzPRtuuq8zkGwRXuFsuKpS/mSzYmhlqR8+FsfdYJcorYo28Y 5quCZ6D2AVYQV/WDZE+uZOVmgVza8qUVL6Tncckj3EgDNpuFd/hv/LWdchiV4tH9+v/9j NvwpLLMxpq0Fcv3YlPZpVE0uOUZs6q9ofGgWOY31huFDlYUULGcdiBczz8WDahNa/b4uL psR4YftjtPJcIKG2tW212yt1ItonFzmgcZgKMJNI9dNqEFOpnfQNNH8rKrB9sAVyDOsRn 3RFASwHLFI9q6A8NH91nxY1novpZFSI4sGmKknFiOiyXX3SjD72oQe2lby6fAe30vsw== 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=MujFOT4c; 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 EC73D606AB1A; Wed, 4 Nov 2026 22:35:27 +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=MujFOT4c Received: by smtp.kernel.org (Postfix) with ESMTPSA id 8614F1F0093A; Wed, 4 Nov 2026 22:35:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1793831727; bh=MXdyztOkoUIF/MY4EG3Ev+5joYjKeRacNX9+s53tt+c=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=MujFOT4cZGqSTRcYx1OGyVSAQ6EryjNIPUj/MtzUYr7icd9BTWfhpxjKTZ/VnhQBG fAPl79rEDX5r2Qb3WPK8jhWPBVlJD3ubxW78fbSVlwMhynApcyOUrxJUCMCbCvc8G3 zOb7al9bmDYX5mVI9yn5OKxPxOjR62xoF2r9QSxQ= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Benjamin Coddington , Anna Schumaker Subject: [PATCH 6.18 0877/1005] NFSv4/filelayout: Anchor page coalescing on pattern_offset Date: Wed, 4 Nov 2026 16:10:10 -0500 Message-ID: <20261104211107.814902731@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: Benjamin Coddington commit 7f2d221b01f356b6bb3bb6efef998f8b28339824 upstream. filelayout_pg_test() bounds page coalescing to a single stripe unit using an offset relative to pls_range.offset, but the data server is selected by nfs4_fl_calc_j_index() using an offset relative to pattern_offset. When a segment's pattern_offset and range offset are not congruent modulo the stripe unit, the coalescing window is shifted off the DS-selection grid, so a coalesced I/O can straddle a stripe boundary and send the bytes past it to the wrong data server. Anchor coalescing on pattern_offset to match nfs4_fl_calc_j_index(). Stripe-congruent segments, including the common whole-file pattern_offset 0 case, are unchanged. Fixes: c6194271f94b ("pnfs: filelayout: support non page aligned layouts") Cc: stable@vger.kernel.org Assisted-by: Claude:claude-opus-4-8 Signed-off-by: Benjamin Coddington Signed-off-by: Anna Schumaker Signed-off-by: Greg Kroah-Hartman --- fs/nfs/filelayout/filelayout.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) --- a/fs/nfs/filelayout/filelayout.c +++ b/fs/nfs/filelayout/filelayout.c @@ -796,7 +796,7 @@ filelayout_pg_test(struct nfs_pageio_des unsigned int size; u64 p_stripe, r_stripe; u32 stripe_offset; - u64 segment_offset = pgio->pg_lseg->pls_range.offset; + u64 pattern_offset = FILELAYOUT_LSEG(pgio->pg_lseg)->pattern_offset; u32 stripe_unit = FILELAYOUT_LSEG(pgio->pg_lseg)->stripe_unit; /* calls nfs_generic_pg_test */ @@ -808,8 +808,8 @@ filelayout_pg_test(struct nfs_pageio_des /* see if req and prev are in the same stripe */ if (prev) { - p_stripe = (u64)req_offset(prev) - segment_offset; - r_stripe = (u64)req_offset(req) - segment_offset; + p_stripe = (u64)req_offset(prev) - pattern_offset; + r_stripe = (u64)req_offset(req) - pattern_offset; do_div(p_stripe, stripe_unit); do_div(r_stripe, stripe_unit); @@ -818,7 +818,7 @@ filelayout_pg_test(struct nfs_pageio_des } /* calculate remaining bytes in the current stripe */ - div_u64_rem((u64)req_offset(req) - segment_offset, + div_u64_rem((u64)req_offset(req) - pattern_offset, stripe_unit, &stripe_offset); WARN_ON_ONCE(stripe_offset > stripe_unit);