linux-kernel - [PATCH v5 6/8] PCI: endpoint: pci-epf-test: Don't free doorbell IRQ unless requested

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20260209062952.2049053-7-den@valinux.co.jp>
Date: Mon,  9 Feb 2026 15:29:49 +0900
From: Koichiro Den <den@...inux.co.jp>
To: vkoul@...nel.org,
	mani@...nel.org,
	Frank.Li@....com,
	cassel@...nel.org,
	jingoohan1@...il.com,
	lpieralisi@...nel.org,
	kwilczynski@...nel.org,
	robh@...nel.org,
	bhelgaas@...gle.com,
	kishon@...nel.org,
	jdmason@...zu.us,
	allenbh@...il.com
Cc: dmaengine@...r.kernel.org,
	linux-pci@...r.kernel.org,
	ntb@...ts.linux.dev,
	linux-kselftest@...r.kernel.org,
	linux-kernel@...r.kernel.org
Subject: [PATCH v5 6/8] PCI: endpoint: pci-epf-test: Don't free doorbell IRQ unless requested

pci_epf_test_enable_doorbell() allocates a doorbell and then installs
the interrupt handler with request_threaded_irq(). On failures before
the IRQ is successfully requested (e.g. no free BAR,
request_threaded_irq() failure), the error path jumps to
err_doorbell_cleanup and calls pci_epf_test_doorbell_cleanup().

pci_epf_test_doorbell_cleanup() unconditionally calls free_irq() for the
doorbell virq, which can trigger "Trying to free already-free IRQ"
warnings when the IRQ was never requested.

Track whether the doorbell IRQ has been successfully requested and only
call free_irq() when it has.

Fixes: eff0c286aa91 ("PCI: endpoint: pci-epf-test: Add doorbell test support")
Signed-off-by: Koichiro Den <den@...inux.co.jp>
---
 drivers/pci/endpoint/functions/pci-epf-test.c | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/drivers/pci/endpoint/functions/pci-epf-test.c b/drivers/pci/endpoint/functions/pci-epf-test.c
index 6952ee418622..23034f548c90 100644
--- a/drivers/pci/endpoint/functions/pci-epf-test.c
+++ b/drivers/pci/endpoint/functions/pci-epf-test.c
@@ -86,6 +86,7 @@ struct pci_epf_test {
 	bool			dma_private;
 	const struct pci_epc_features *epc_features;
 	struct pci_epf_bar	db_bar;
+	bool			db_irq_requested;
 	size_t			bar_size[PCI_STD_NUM_BARS];
 };
 
@@ -715,7 +716,10 @@ static void pci_epf_test_doorbell_cleanup(struct pci_epf_test *epf_test)
 	struct pci_epf_test_reg *reg = epf_test->reg[epf_test->test_reg_bar];
 	struct pci_epf *epf = epf_test->epf;
 
-	free_irq(epf->db_msg[0].virq, epf_test);
+	if (epf_test->db_irq_requested && epf->db_msg) {
+		free_irq(epf->db_msg[0].virq, epf_test);
+		epf_test->db_irq_requested = false;
+	}
 	reg->doorbell_bar = cpu_to_le32(NO_BAR);
 
 	pci_epf_free_doorbell(epf);
@@ -741,6 +745,8 @@ static void pci_epf_test_enable_doorbell(struct pci_epf_test *epf_test,
 	if (bar < BAR_0)
 		goto err_doorbell_cleanup;
 
+	epf_test->db_irq_requested = false;
+
 	ret = request_threaded_irq(epf->db_msg[0].virq, NULL,
 				   pci_epf_test_doorbell_handler, IRQF_ONESHOT,
 				   "pci-ep-test-doorbell", epf_test);
@@ -751,6 +757,7 @@ static void pci_epf_test_enable_doorbell(struct pci_epf_test *epf_test,
 		goto err_doorbell_cleanup;
 	}
 
+	epf_test->db_irq_requested = true;
 	reg->doorbell_data = cpu_to_le32(msg->data);
 	reg->doorbell_bar = cpu_to_le32(bar);
 
-- 
2.51.0