From 7e89efc6e9e402839643cb297bab14055c547f07 Mon Sep 17 00:00:00 2001 From: Dave Jiang Date: Thu, 2 May 2024 09:57:31 -0700 Subject: PCI: Lock upstream bridge for pci_reset_function() Fix a long-standing locking gap for missing pci_cfg_access_lock() while manipulating bridge reset registers and configuration during pci_reset_bus_function(). If there is an upstream bridge, lock it before locking the device itself. pci_dev_lock() calls pci_cfg_access_lock(), which blocks the writing of PCI config space by user space. Add lockdep assertion via pci_dev->cfg_access_lock to verify pci_dev->block_cfg_access is set. Co-developed-by: Dan Williams Link: https://lore.kernel.org/r/20240502165851.1948523-3-dave.jiang@intel.com Signed-off-by: Dan Williams Signed-off-by: Dave Jiang [bhelgaas: commit log] Signed-off-by: Bjorn Helgaas --- drivers/pci/probe.c | 3 +++ 1 file changed, 3 insertions(+) (limited to 'drivers/pci/probe.c') diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c index 1325fbae2f28..a3da776bf986 100644 --- a/drivers/pci/probe.c +++ b/drivers/pci/probe.c @@ -2543,6 +2543,9 @@ void pci_device_add(struct pci_dev *dev, struct pci_bus *bus) dev->dev.dma_mask = &dev->dma_mask; dev->dev.dma_parms = &dev->dma_parms; dev->dev.coherent_dma_mask = 0xffffffffull; + lockdep_register_key(&dev->cfg_access_key); + lockdep_init_map(&dev->cfg_access_lock, dev_name(&dev->dev), + &dev->cfg_access_key, 0); dma_set_max_seg_size(&dev->dev, 65536); dma_set_seg_boundary(&dev->dev, 0xffffffff); -- cgit v1.2.3