From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 CD9FB495050; Mon, 31 Aug 2026 13:38:41 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788183523; cv=none; b=KPGwucoJO+t2/stFfcrPXKfMZtInHJS51IcpoulXjbAutyGCsUCSlqwUCjUba1y7zD1s0fwUSNjnXdofuPiUMH4RtUuCRgF7CumUR/10Izz0WCqDENdcMH5g35ikM8HztBl+wdlOMtjMPDa15XpKyOJhtsJAuWBsFPI1cqw8RtQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788183523; c=relaxed/simple; bh=UWju7fNSRBKf2JiHbeAuuGlZTiy+uM9QILL1TtaT3wo=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=QDBJU0aimaoVs4KO/aubqYtxDYCE4ddEKuBVrt6rpcjZwj0dVJ/MhFoseWu1P7vR/x2QAkWJSOXkguvlpFGF0IdaIGKNhWeuNPeNIWzWY9zoTX5nD21ddzoWOe+AT9xVZvwJbeuKIpeUPPq2xzRnNwwsWBIQli5rI+mpRXBeGY8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=QkrNs2jU; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="QkrNs2jU" Received: by smtp.kernel.org (Postfix) with ESMTPSA id AC0D51F00ACA; Mon, 31 Aug 2026 13:38:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1788183521; bh=BEa31oEK8chBTBa5hgT2yutVrQ4YqkstTuvOGNMi48Y=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=QkrNs2jUsRz/RqcsWoEFt/iU0NEOKJEjVLdaAe/WtyeVFhp1qr1G1D5bDLucDNKDM ejSiuOKii/xp633xJ5GfXeMAK36hw+eZat0zICcCdQMi1uVtAUQT6FI9yaMTEUaX5W Zn74pmBeUbB6NUksmkmbyXNZx2q9ShAdnLv/JUupOMwlcFvU7maDcRAc0hXBzzRXHu vKuRQovqTxAg29fEOq5r7xfHMV+uV9lUQzDp+BTlp0ANmGU+qvLaMRYQxY4CH2RVFp NRGDsMtDknGAGfpWAzkav7N0ORTIDpsMcfxVBj2KVh+MkQXh8/MmEn6thK0iapD1Ol p1C3l57CYEjKA== From: Sasha Levin To: patches@lists.linux.dev, stable@vger.kernel.org Cc: Yao Sang , Christoph Hellwig , Keith Busch , Sasha Levin , sagi@grimberg.me, linux-nvme@lists.infradead.org, linux-kernel@vger.kernel.org Subject: [PATCH AUTOSEL 6.18-6.12] nvme: refresh multipath head zoned limits from path limits Date: Mon, 31 Aug 2026 09:22:54 -0400 Message-ID: <20260831133314.4125787-146-sashal@kernel.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260831133314.4125787-1-sashal@kernel.org> References: <20260831133314.4125787-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore X-stable-base: Linux 6.18.48 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: Yao Sang [ Upstream commit 59c0517123f2757c41d7795f841bc4c836577d17 ] queue_limits_stack_bdev() updates the multipath head limits from the path queue, but it does not propagate max_open_zones or max_active_zones. As a result, a zoned multipath namespace head can keep stale 0/0 values even after a ready path reports finite zoned resource limits. When refreshing the head limits in nvme_update_ns_info(), stack the zoned resource limits directly after stacking the path queue limits. Use min_not_zero() so the block layer's 0 value keeps its "no limit" meaning while finite limits are combined conservatively. This avoids advertising "no limit" on the multipath head while keeping the zoned-limit handling local to the NVMe multipath update path. Reviewed-by: Christoph Hellwig Signed-off-by: Yao Sang Signed-off-by: Keith Busch Signed-off-by: Sasha Levin --- LLM Generated explanations, may be completely bogus: The background searches finished: - **Local tree search** (`git log --grep=...`): No match for this patch in the checked-out **6.18.44** tree — expected, since `nvme_stack_zone_resources()` isn’t there yet. - **Mainline search** (`build/master`): Timed out after ~3 minutes. Partial output only showed unrelated zoned-limit commits; no sign of this NVMe multipath fix on the fetched `master` tip. That lines up with the earlier analysis: the bug is present in **6.18.y**, the fix is small and correct, and the backport recommendation remains **YES**. drivers/nvme/host/core.c | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c index 8feb774616029..43cbbcd3796b1 100644 --- a/drivers/nvme/host/core.c +++ b/drivers/nvme/host/core.c @@ -2450,6 +2450,14 @@ static int nvme_update_ns_info_block(struct nvme_ns *ns, return ret; } +static void nvme_stack_zone_resources(struct queue_limits *t, + const struct queue_limits *b) +{ + t->max_open_zones = min_not_zero(t->max_open_zones, b->max_open_zones); + t->max_active_zones = + min_not_zero(t->max_active_zones, b->max_active_zones); +} + static int nvme_update_ns_info(struct nvme_ns *ns, struct nvme_ns_info *info) { bool unsupported = false; @@ -2516,6 +2524,8 @@ static int nvme_update_ns_info(struct nvme_ns *ns, struct nvme_ns_info *info) lim.io_opt = ns_lim->io_opt; queue_limits_stack_bdev(&lim, ns->disk->part0, 0, ns->head->disk->disk_name); + if (lim.features & BLK_FEAT_ZONED) + nvme_stack_zone_resources(&lim, ns_lim); if (unsupported) ns->head->disk->flags |= GENHD_FL_HIDDEN; else -- 2.53.0