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From: Bartosz Golaszewski <brgl@bgdev.pl>
To: Bjorn Helgaas <bhelgaas@google.com>
Cc: linux-kernel@vger.kernel.org,
	linux-pci@vger.kernel.org,
	Bartosz Golaszewski <bartosz.golaszewski@linaro.org>,
	Amit Pundir <amit.pundir@linaro.org>,
	Neil Armstrong <neil.armstrong@linaro.org>,
	Caleb Connolly <caleb.connolly@linaro.org>
Subject: [PATCH v9 1/5] PCI: Hold the rescan mutex when scanning for the first time
Date: Wed, 12 Jun 2024 10:20:14 +0200
Message-ID: <20240612082019.19161-2-brgl@bgdev.pl>
In-Reply-To: <20240612082019.19161-1-brgl@bgdev.pl>
References: <20240612082019.19161-1-brgl@bgdev.pl>
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From: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>

With the introduction of PCI device power control drivers that will be
able to trigger the port rescan when probing, we need to hold the rescan
mutex during the initial pci_host_probe() too or the two could get in
each other's way.

Tested-by: Amit Pundir <amit.pundir@linaro.org>
Tested-by: Neil Armstrong <neil.armstrong@linaro.org> # on SM8550-QRD, SM8650-QRD & SM8650-HDK
Tested-by: Caleb Connolly <caleb.connolly@linaro.org> # OnePlus 8T
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
---
 drivers/pci/probe.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index bfeeaf2d1fa9..b14b9876c030 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -3083,7 +3083,9 @@ int pci_host_probe(struct pci_host_bridge *bridge)
 	struct pci_bus *bus, *child;
 	int ret;
 
+	pci_lock_rescan_remove();
 	ret = pci_scan_root_bus_bridge(bridge);
+	pci_unlock_rescan_remove();
 	if (ret < 0) {
 		dev_err(bridge->dev.parent, "Scanning root bridge failed");
 		return ret;
-- 
2.40.1