PCI : Calculate right add_size (a4ac9fea) · Commits · e / devices / android_kernel_fairphone_FP5

During debug of one SRIOV enabled hotplug device, we found found that add_size is not passed properly. The device has devices under two level bridges: +-[0000:80]-+-00.0-[81-8f]-- | +-01.0-[90-9f]-- | +-02.0-[a0-af]----00.0-[a1-a3]--+-02.0-[a2]--+-00.0 Oracle Corporation Device | | \-03.0-[a3]--+-00.0 Oracle Corporation Device Which means later the parent bridge will not try to add a big enough range: [ 557.455077] pci 0000:a0:00.0: BAR 14: assigned [mem 0xf9000000-0xf93fffff] [ 557.461974] pci 0000:a0:00.0: BAR 15: assigned [mem 0xf6000000-0xf61fffff pref] [ 557.469340] pci 0000:a1:02.0: BAR 14: assigned [mem 0xf9000000-0xf91fffff] [ 557.476231] pci 0000:a1:02.0: BAR 15: assigned [mem 0xf6000000-0xf60fffff pref] [ 557.483582] pci 0000:a1:03.0: BAR 14: assigned [mem 0xf9200000-0xf93fffff] [ 557.490468] pci 0000:a1:03.0: BAR 15: assigned [mem 0xf6100000-0xf61fffff pref] [ 557.497833] pci 0000:a1:03.0: BAR 14: can't assign mem (size 0x200000) [ 557.504378] pci 0000:a1:03.0: failed to add optional resources res=[mem 0xf9200000-0xf93fffff] [ 557.513026] pci 0000:a1:02.0: BAR 14: can't assign mem (size 0x200000) [ 557.519578] pci 0000:a1:02.0: failed to add optional resources res=[mem 0xf9000000-0xf91fffff] It turns out we did not calculate size1 properly. static resource_size_t calculate_memsize(resource_size_t size, resource_size_t min_size, resource_size_t size1, resource_size_t old_size, resource_size_t align) { if (size < min_size) size = min_size; if (old_size == 1 ) old_size = 0; if (size < old_size) size = old_size; size = ALIGN(size + size1, align); return size; } We should not pass add_size with min_size in calculate_memsize since that will make add_size not contribute final add_size. So just pass add_size with size1 to calculate_memsize(). With this change, we should have chance to remove extra addon in pci_reassign_resource. Signed-off-by:

Yinghai Lu <yinghai@kernel.org> Signed-off-by:

Jesse Barnes <jbarnes@virtuousgeek.org>

drivers/pci/setup-bus.c

+2 −2

Original line number	Original line	Diff line number	Diff line
	@@ -612,7 +612,7 @@ static void pbus_size_io(struct pci_bus *bus, resource_size_t min_size,
	if (children_add_size > add_size)		if (children_add_size > add_size)
	add_size = children_add_size;		add_size = children_add_size;
	size1 = (!realloc_head \|\| (realloc_head && !add_size)) ? size0 :		size1 = (!realloc_head \|\| (realloc_head && !add_size)) ? size0 :
	calculate_iosize(size, min_size+add_size, size1,		calculate_iosize(size, min_size, add_size + size1,
	resource_size(b_res), 4096);		resource_size(b_res), 4096);
	if (!size0 && !size1) {		if (!size0 && !size1) {
	if (b_res->start \|\| b_res->end)		if (b_res->start \|\| b_res->end)
	@@ -726,7 +726,7 @@ static int pbus_size_mem(struct pci_bus *bus, unsigned long mask,
	if (children_add_size > add_size)		if (children_add_size > add_size)
	add_size = children_add_size;		add_size = children_add_size;
	size1 = (!realloc_head \|\| (realloc_head && !add_size)) ? size0 :		size1 = (!realloc_head \|\| (realloc_head && !add_size)) ? size0 :
	calculate_memsize(size, min_size+add_size, 0,		calculate_memsize(size, min_size, add_size,
	resource_size(b_res), min_align);		resource_size(b_res), min_align);
	if (!size0 && !size1) {		if (!size0 && !size1) {
	if (b_res->start \|\| b_res->end)		if (b_res->start \|\| b_res->end)

drivers/pci/setup-res.c

+3 −2

Original line number	Original line	Diff line number	Diff line
	@@ -255,11 +255,12 @@ int pci_reassign_resource(struct pci_dev *dev, int resno, resource_size_t addsiz
	return -EINVAL;		return -EINVAL;
	}		}

	new_size = resource_size(res) + addsize + min_align;		/* already aligned with min_align */
			new_size = resource_size(res) + addsize;
	ret = _pci_assign_resource(dev, resno, new_size, min_align);		ret = _pci_assign_resource(dev, resno, new_size, min_align);
	if (!ret) {		if (!ret) {
	res->flags &= ~IORESOURCE_STARTALIGN;		res->flags &= ~IORESOURCE_STARTALIGN;
	dev_info(&dev->dev, "BAR %d: assigned %pR\n", resno, res);		dev_info(&dev->dev, "BAR %d: reassigned %pR\n", resno, res);
	if (resno < PCI_BRIDGE_RESOURCES)		if (resno < PCI_BRIDGE_RESOURCES)
	pci_update_resource(dev, resno);		pci_update_resource(dev, resno);
	}		}