From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To: stable@vger.kernel.org
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	patches@lists.linux.dev,
	Sven Peter <sven@kernel.org>,
	Nick Chan <towinchenmi@gmail.com>,
	Keith Busch <kbusch@kernel.org>,
	Sasha Levin <sashal@kernel.org>
Subject: [PATCH 6.12 1354/1376] nvme-apple: Prevent shared tags across queues on Apple A11
Date: Sat, 12 Sep 2026 09:03:00 +0200
Message-ID: <20260912065637.710882753@linuxfoundation.org>
In-Reply-To: <20260912065607.535295758@linuxfoundation.org>
References: <20260912065607.535295758@linuxfoundation.org>
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6.12-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Nick Chan <towinchenmi@gmail.com>

[ Upstream commit 6fe0687245e8406bf26143bd45eb16441bbe5280 ]

On Apple A11, tags of pending commands must be unique across the admin
and IO queues, else the firmware crashes with
"duplicate tag error for tag N", with N being the tag.

Apply the existing workaround for M1 of reserving two tags for the admin
queue to A11.

Cc: stable@vger.kernel.org
Fixes: 04d8ecf37b5e ("nvme: apple: Add Apple A11 support")
Reviewed-by: Sven Peter <sven@kernel.org>
Signed-off-by: Nick Chan <towinchenmi@gmail.com>
Signed-off-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/nvme/host/apple.c | 12 ++++--------
 1 file changed, 4 insertions(+), 8 deletions(-)

diff --git a/drivers/nvme/host/apple.c b/drivers/nvme/host/apple.c
index 5f745bf615fe7..1cc222fdbf22e 100644
--- a/drivers/nvme/host/apple.c
+++ b/drivers/nvme/host/apple.c
@@ -239,7 +239,7 @@ static unsigned int apple_nvme_queue_depth(struct apple_nvme_queue *q)
 {
 	struct apple_nvme *anv = queue_to_apple_nvme(q);
 
-	if (q->is_adminq && anv->hw->has_lsq_nvmmu)
+	if (q->is_adminq)
 		return APPLE_NVME_AQ_DEPTH;
 
 	return anv->hw->max_queue_depth;
@@ -317,7 +317,7 @@ static void apple_nvme_submit_cmd_t8015(struct apple_nvme_queue *q,
 		memcpy((void *)q->sqes + (q->sq_tail << APPLE_NVME_IOSQES),
 			cmd, sizeof(*cmd));
 
-	if (++q->sq_tail == anv->hw->max_queue_depth)
+	if (++q->sq_tail == apple_nvme_queue_depth(q))
 		q->sq_tail = 0;
 
 	writel(q->sq_tail, q->sq_db);
@@ -1130,10 +1130,7 @@ static void apple_nvme_reset_work(struct work_struct *work)
 	}
 
 	/* Setup the admin queue */
-	if (anv->hw->has_lsq_nvmmu)
-		aqa = APPLE_NVME_AQ_DEPTH - 1;
-	else
-		aqa = anv->hw->max_queue_depth - 1;
+	aqa = APPLE_NVME_AQ_DEPTH - 1;
 	aqa |= aqa << 16;
 	writel(aqa, anv->mmio_nvme + NVME_REG_AQA);
 	writeq(anv->adminq.sq_dma_addr, anv->mmio_nvme + NVME_REG_ASQ);
@@ -1316,8 +1313,7 @@ static int apple_nvme_alloc_tagsets(struct apple_nvme *anv)
 	 * both queues. The admin queue gets the first APPLE_NVME_AQ_DEPTH which
 	 * must be marked as reserved in the IO queue.
 	 */
-	if (anv->hw->has_lsq_nvmmu)
-		anv->tagset.reserved_tags = APPLE_NVME_AQ_DEPTH;
+	anv->tagset.reserved_tags = APPLE_NVME_AQ_DEPTH;
 	anv->tagset.queue_depth = anv->hw->max_queue_depth - 1;
 	anv->tagset.timeout = NVME_IO_TIMEOUT;
 	anv->tagset.numa_node = NUMA_NO_NODE;
-- 
2.53.0