FAILED: patch "[PATCH] octeontx2-pf: clear stale mailbox IRQ state before" failed to apply to 5.10-stable tree

The patch below does not apply to the 5.10-stable tree.
If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <[email protected]>.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.10.y
git checkout FETCH_HEAD
git cherry-pick -x f918554fb7246e89b98ef90abe80801f038258b3
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<[email protected]>' --in-reply-to '2026072014-quake-amber-fee6@gregkh' --subject-prefix 'PATCH 5.10.y' 'HEAD^..'

Possible dependencies:

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From f918554fb7246e89b98ef90abe80801f038258b3 Mon Sep 17 00:00:00 2001
From: Runyu Xiao <[email protected]>
Date: Fri, 12 Jun 2026 00:00:13 +0800
Subject: [PATCH] octeontx2-pf: clear stale mailbox IRQ state before
request_irq()

otx2_register_mbox_intr() currently installs the PF mailbox IRQ handler before clearing stale mailbox interrupt state. The function itself then comments that the local interrupt bits must be cleared first to avoid spurious interrupts, but that clear happens only after request_irq() has already exposed the handler to irq delivery.

A running system can reach this during PF mailbox interrupt registration while stale or latched RVU_PF_INT state is still present. If delivery happens in the request_irq()-to-clear window, otx2_pfaf_mbox_intr_handler() can run before local quiesce and touch the same pf->mbox and pf->mbox_wq carrier that probe and teardown later reuse or destroy.

Move the stale mailbox interrupt clear ahead of request_irq(), but keep interrupt enabling after the handler is installed. This closes the pre-clear early-IRQ window without creating a new enable-before-handler window.

index f9fbf0c17648..0311357dd05b 100644
@@ -1119,9 +1119,16 @@ int otx2_register_mbox_intr(struct otx2_nic *pf, bool probe_af)
 {
 	struct otx2_hw *hw = &pf->hw;
 	struct msg_req *req;
+	u64 mbox_int_mask;
 	char *irq_name;
 	int err;
 
+	mbox_int_mask = !is_cn20k(pf->pdev) ? BIT_ULL(0) :
+				BIT_ULL(0) | BIT_ULL(1);
+
+	/* Clear stale mailbox interrupt state before installing the handler. */
+	otx2_write64(pf, RVU_PF_INT, mbox_int_mask);
+
 	/* Register mailbox interrupt handler */
 	if (!is_cn20k(pf->pdev)) {
 		irq_name = &hw->irq_name[RVU_PF_INT_VEC_AFPF_MBOX * NAME_SIZE];

@@ -1147,17 +1154,8 @@ int otx2_register_mbox_intr(struct otx2_nic *pf, bool probe_af)
 		return err;
 	}
 
-	/* Enable mailbox interrupt for msgs coming from AF.
-	 * First clear to avoid spurious interrupts, if any.
-	 */
-	if (!is_cn20k(pf->pdev)) {
-		otx2_write64(pf, RVU_PF_INT, BIT_ULL(0));
-		otx2_write64(pf, RVU_PF_INT_ENA_W1S, BIT_ULL(0));
-	} else {
-		otx2_write64(pf, RVU_PF_INT, BIT_ULL(0) | BIT_ULL(1));
-		otx2_write64(pf, RVU_PF_INT_ENA_W1S, BIT_ULL(0) |
-			     BIT_ULL(1));
-	}
+	/* Enable mailbox interrupt for msgs coming from AF. */
+	otx2_write64(pf, RVU_PF_INT_ENA_W1S, mbox_int_mask);
 
 	if (!probe_af)
 		return 0;

From: Subbaraya Sundeep <[email protected]>

[ Upstream commit d0976b43956ee8c8bd093223df9115bfcf63dfe5 ]

This patch removes unnecessary typecasts by marking the mbox_regions array as __iomem since it is used to store pointers to memory-mapped I/O (MMIO) regions. Also simplified the call to readq() in PF driver by removing redundant type casts.

Stable-dep-of: f918554fb724 ("octeontx2-pf: clear stale mailbox IRQ state before request_irq()")

---
 drivers/net/ethernet/marvell/octeontx2/nic/otx2_pf.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

index 1516f248377549..747dfa4ee68748 100644
@@ -593,7 +593,7 @@ static int otx2_pfvf_mbox_init(struct otx2_nic *pf, int numvfs)
 	if (!pf->mbox_pfvf_wq)
 		return -ENOMEM;
 
-	base = readq((void __iomem *)((u64)pf->reg_base + RVU_PF_VF_BAR4_ADDR));
+	base = readq(pf->reg_base + RVU_PF_VF_BAR4_ADDR);
 	hwbase = ioremap_wc(base, MBOX_SIZE * pf->total_vfs);
 
 	if (!hwbase) {

2.53.0

From: Runyu Xiao <[email protected]>

[ Upstream commit f918554fb7246e89b98ef90abe80801f038258b3 ]

otx2_register_mbox_intr() currently installs the PF mailbox IRQ handler before clearing stale mailbox interrupt state. The function itself then comments that the local interrupt bits must be cleared first to avoid spurious interrupts, but that clear happens only after request_irq() has already exposed the handler to irq delivery.

A running system can reach this during PF mailbox interrupt registration while stale or latched RVU_PF_INT state is still present. If delivery happens in the request_irq()-to-clear window, otx2_pfaf_mbox_intr_handler() can run before local quiesce and touch the same pf->mbox and pf->mbox_wq carrier that probe and teardown later reuse or destroy.

Move the stale mailbox interrupt clear ahead of request_irq(), but keep interrupt enabling after the handler is installed. This closes the pre-clear early-IRQ window without creating a new enable-before-handler window.

---
 drivers/net/ethernet/marvell/octeontx2/nic/otx2_pf.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

index 747dfa4ee68748..4b23947d000289 100644
@@ -979,6 +979,9 @@ static int otx2_register_mbox_intr(struct otx2_nic *pf, bool probe_af)
 	char *irq_name;
 	int err;
 
+	/* Clear stale mailbox interrupt state before installing the handler. */
+	otx2_write64(pf, RVU_PF_INT, BIT_ULL(0));
+
 	/* Register mailbox interrupt handler */
 	irq_name = &hw->irq_name[RVU_PF_INT_VEC_AFPF_MBOX * NAME_SIZE];
 	snprintf(irq_name, NAME_SIZE, "RVUPFAF Mbox");

@@ -990,10 +993,7 @@ static int otx2_register_mbox_intr(struct otx2_nic *pf, bool probe_af)
 		return err;
 	}
 
-	/* Enable mailbox interrupt for msgs coming from AF.
-	 * First clear to avoid spurious interrupts, if any.
-	 */
-	otx2_write64(pf, RVU_PF_INT, BIT_ULL(0));
+	/* Enable mailbox interrupt for msgs coming from AF. */
 	otx2_write64(pf, RVU_PF_INT_ENA_W1S, BIT_ULL(0));
 
 	if (!probe_af)

2.53.0