Commit 47b802d5 authored Jan 13, 2020 by Chen Yu Committed by Bjorn Helgaas Jan 13, 2020

PCI/PM: Print config space of devices before suspend

When resuming from hibernation (S4, also known as "suspend to disk") on a
VM, we have seen invalid config space, e.g.,

  serial 0000:00:16.3: restoring config space at offset 0x14 (was 0x9104e000, writing 0xffffffff)

To help debug problems like this, log the config space being saved before
suspend, similar to the log in pci_restore_config_dword() when resuming.

Link: https://lore.kernel.org/r/20200113060724.19571-1-yu.c.chen@intel.com


[bhelgaas: commit log]
Signed-off-by: Chen Yu <yu.c.chen@intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Cc: Len Brown <lenb@kernel.org>

parent e42617b8

drivers/pci/pci.c

+4 −1

Original line number	Diff line number	Diff line
		@@ -1372,8 +1372,11 @@ int pci_save_state(struct pci_dev *dev)
		{
		int i;
		/* XXX: 100% dword access ok here? */
		for (i = 0; i < 16; i++)
		for (i = 0; i < 16; i++) {
		pci_read_config_dword(dev, i * 4, &dev->saved_config_space[i]);
		pci_dbg(dev, "saving config space at offset %#x (reading %#x)\n",
		i * 4, dev->saved_config_space[i]);
		}
		dev->state_saved = true;

		i = pci_save_pcie_state(dev);

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