Re: WARNING at drivers/pci/setup-bus.c:2373, bisected to "PCI: Use pbus_select_window_for_type() during mem window sizing"

[Klaus Kudielka <klaus.kudielka@gmail.com>]

On Sat, 2025-10-18 at 10:14 +0200, Klaus Kudielka wrote:

[...]


> Device tree: arch/arm/boot/dts/marvell/armada-385-turris-omnia.dts
> PCI driver: pci-mvebu
> Hardware status: The joint mPCIe / mSATA slot carries an mSATA drive, the other
> two mPCIe slots carry WiFi cards.
> 
> As far as I can tell, hardware is operating nominally, so the warning looks like
> a false positive.


In the meantime, I stared a bit at the logs, and at the code.


WITH the offending commit, I see TWO identical lines before the WARNING:

> [    0.027107] pci 0000:00:03.0: bridge window [mem 0x00200000-0x003fffff] to [bus 02] add_size 200000 add_align 200000
> [    0.027115] pci 0000:00:03.0: bridge window [mem 0x00200000-0x003fffff] to [bus 02] add_size 200000 add_align 200000

So, this part of  pbus_size_mem() now seems to be called *TWICE* for the same bridge window:

		add_to_list(realloc_head, bus->self, b_res, size1-size0, add_align);
		pci_info(bus->self, "bridge window %pR to %pR add_size %llx add_align %llx\n",
			   b_res, &bus->busn_res,
			   (unsigned long long) (size1 - size0),
			   (unsigned long long) add_align);



WITHOUT the offending commit, I see only one line, and no WARNING.
> [    0.027405] pci 0000:00:03.0: bridge window [mem 0x00200000-0x003fffff] to [bus 02] add_size 200000 add_align 200000


This behavior change really looks suspicious to me (maybe resulting in two identical entries in the realloc_list).
Does that ring any bell?


Thanks, Klaus