diff mbox

Assign mem resource fail after remove and rescan

Message ID CAE9FiQUQ_Kz8sNzu9RmOfoe4xEwfZ3atGcfQ39UAp4dRz2rRFA@mail.gmail.com
State Changes Requested
Headers show

Commit Message

Yinghai Lu April 1, 2015, 10:21 p.m. UTC 
On Mon, Mar 30, 2015 at 11:38 PM, Yijing Wang <wangyijing@huawei.com> wrote:
> On 2015/3/29 14:18, Yinghai Lu wrote:
>> On Sat, Mar 28, 2015 at 3:02 AM, Yijing Wang <wangyijing@huawei.com> wrote:
>>> ...
>>>
>>> I compared above log and found after we did remove and rescan, the bridge requested resource size extended to 0x06000000,
>>> and when system boot up, it requested only 0x4800000.
>>>
>    I tested it, remove and rescan 05:19.0 device is ok now, but
> if do the operations for the parent device of 05:19.0, the result is
> still fail.

Found the problem, attached patch should fix the problem.

Thanks

Yinghai

Comments

Yijing Wang April 2, 2015, 8:35 a.m. UTC | #1 
On 2015/4/2 6:21, Yinghai Lu wrote:
> On Mon, Mar 30, 2015 at 11:38 PM, Yijing Wang <wangyijing@huawei.com> wrote:
>> On 2015/3/29 14:18, Yinghai Lu wrote:
>>> On Sat, Mar 28, 2015 at 3:02 AM, Yijing Wang <wangyijing@huawei.com> wrote:
>>>> ...
>>>>
>>>> I compared above log and found after we did remove and rescan, the bridge requested resource size extended to 0x06000000,
>>>> and when system boot up, it requested only 0x4800000.
>>>>
>>    I tested it, remove and rescan 05:19.0 device is ok now, but
>> if do the operations for the parent device of 05:19.0, the result is
>> still fail.
> 
> Found the problem, attached patch should fix the problem.

Thanks, will test soon.

> 
> Thanks
> 
> Yinghai
>
Yijing Wang April 9, 2015, 11:12 a.m. UTC | #2 
On 2015/4/2 6:21, Yinghai Lu wrote:
> On Mon, Mar 30, 2015 at 11:38 PM, Yijing Wang <wangyijing@huawei.com> wrote:
>> On 2015/3/29 14:18, Yinghai Lu wrote:
>>> On Sat, Mar 28, 2015 at 3:02 AM, Yijing Wang <wangyijing@huawei.com> wrote:
>>>> ...
>>>>
>>>> I compared above log and found after we did remove and rescan, the bridge requested resource size extended to 0x06000000,
>>>> and when system boot up, it requested only 0x4800000.
>>>>
>>    I tested it, remove and rescan 05:19.0 device is ok now, but
>> if do the operations for the parent device of 05:19.0, the result is
>> still fail.
> 
> Found the problem, attached patch should fix the problem.


Hi Yinghai, sorry for the delay reply, this fix works, dmesg info:

...
[  181.567872] pci_bus 0000:06: busn_res: [bus 06-ff] end is updated to 12
[  181.567886] pci_bus 0000:05: busn_res: [bus 05-ff] end is updated to 12
[  181.567899] pci_bus 0000:04: busn_res: [bus 04-12] end is updated to 12
[  181.567928] pci_bus 0000:13: busn_res: [bus 13] end is updated to 13
[  181.568177] pci_bus 0000:16: busn_res: [bus 16] end is updated to 16
[  181.568233] pci_bus 0000:17: busn_res: [bus 17] end is updated to 17
[  181.568263] pci_bus 0000:18: busn_res: [bus 18-20] end is updated to 20
[  181.568274] pci_bus 0000:15: busn_res: [bus 15-20] end is updated to 20
[  181.568286] pci_bus 0000:14: busn_res: [bus 14-20] end is updated to 20
[  181.568313] pci_bus 0000:21: busn_res: [bus 21] end is updated to 21
[  181.568323] pci_bus 0000:03: busn_res: [bus 03-21] end is updated to 21
[  181.568333] pci_bus 0000:02: busn_res: [bus 02-21] end is updated to 21
[  181.568355] pci_bus 0000:22: busn_res: [bus 22] end is updated to 22
[  181.568545] pci_bus 0000:24: busn_res: [bus 24] end is updated to 24
[  181.568558] pci_bus 0000:23: busn_res: [bus 23-24] end is updated to 24
[  181.574379] pci 0000:04:00.0: BAR 14: assigned [mem 0xe4000000-0xe87fffff]
[  181.574390] pci 0000:05:19.0: BAR 14: assigned [mem 0xe4000000-0xe87fffff]
[  181.574398] pci 0000:06:00.0: BAR 2: assigned [mem 0xe4000000-0xe7ffffff 64bit]
[  181.574429] pci 0000:06:00.0: BAR 0: assigned [mem 0xe8000000-0xe87fffff]
[  181.574441] pci 0000:05:19.0: PCI bridge to [bus 06-12]
[  181.574456] pci 0000:05:19.0:   bridge window [mem 0xe4000000-0xe87fffff]
[  181.574482] pci 0000:04:00.0: PCI bridge to [bus 05-12]
[  181.574496] pci 0000:04:00.0:   bridge window [mem 0xe4000000-0xe87fffff]
[  181.574528] pci 0000:23:00.0: PCI bridge to [bus 24]
...

> 
> Thanks
> 
> Yinghai
>
Bjorn Helgaas May 5, 2015, 7:07 p.m. UTC | #3 
On Wed, Apr 01, 2015 at 03:21:38PM -0700, Yinghai Lu wrote:
> On Mon, Mar 30, 2015 at 11:38 PM, Yijing Wang <wangyijing@huawei.com> wrote:
> > On 2015/3/29 14:18, Yinghai Lu wrote:
> >> On Sat, Mar 28, 2015 at 3:02 AM, Yijing Wang <wangyijing@huawei.com> wrote:
> >>> ...
> >>>
> >>> I compared above log and found after we did remove and rescan, the bridge requested resource size extended to 0x06000000,
> >>> and when system boot up, it requested only 0x4800000.
> >>>
> >    I tested it, remove and rescan 05:19.0 device is ok now, but
> > if do the operations for the parent device of 05:19.0, the result is
> > still fail.
> 
> Found the problem, attached patch should fix the problem.
> 
> Thanks
> 
> Yinghai

> Subject: [PATCH] PCI: Optimize bus mem sizing to small size
> 
> Current code try to get min_align as possible and use that to
> align final size.
> 
> That could cause generate wrong align/size or too big size in some case.
> 
>  when we have align/size: 16M/64M
>  min_align/size0 will be 8M/64M, that is wrong, align must be 16M.
> 
>  when we have align/size: 1M/1M, 64M/64M,
>  min_align/size0 will be 32M/96M, that is way too big for sum size 65M.
> 
> That will cuase allocation fails.
> 
> The patch introduce max_align/size0_max, and size0_max is just
> sum of all children resource.
> 
> Prefer small size instead of small align. Only use min_align when
> two size is the same.
> 
> The new size will only need to be aligned to bus window alignment.
> 
> Signed-off-by: Yinghai Lu <yinghai@kernel.org>

I'm sorry, I can't make any sense out of this.  I can't understand
what you're trying to say.

A specific simple example might help.

Is this a regression?  Should it be marked for stable?  If so, how far
back?

It doesn't apply on v4.1-rc2 (I would apply it manually if I could
understand the changelog and comments, but you might as well refresh it at
the same time as you rewrite those).

Please include a link to the problem report.

Please include the patch inline in the message.  It is a significant hassle
for me to deal with attachments, and you are the only major contributor who
uses them.

Bjorn

> ---
>  drivers/pci/setup-bus.c |   50 +++++++++++++++++++++++++++++++++++++++++++++---
>  1 file changed, 47 insertions(+), 3 deletions(-)
> 
> Index: linux-2.6/drivers/pci/setup-bus.c
> ===================================================================
> --- linux-2.6.orig/drivers/pci/setup-bus.c
> +++ linux-2.6/drivers/pci/setup-bus.c
> @@ -882,12 +882,14 @@ static void pbus_size_io(struct pci_bus
>  	}
>  
>  	size0 = calculate_iosize(size, min_size, size1,
> -			resource_size(b_res), min_align);
> +				 resource_size(b_res),
> +				 window_alignment(bus, IORESOURCE_IO));
>  	if (children_add_size > add_size)
>  		add_size = children_add_size;
>  	size1 = (!realloc_head || (realloc_head && !add_size)) ? size0 :
>  		calculate_iosize(size, min_size, add_size + size1,
> -			resource_size(b_res), min_align);
> +				 resource_size(b_res),
> +				 window_alignment(bus, IORESOURCE_IO));
>  	if (!size0 && !size1) {
>  		if (b_res->start || b_res->end)
>  			dev_info(&bus->self->dev, "disabling bridge window %pR to %pR (unused)\n",
> @@ -962,6 +964,8 @@ static int pbus_size_mem(struct pci_bus
>  	struct resource *b_res = find_free_bus_resource(bus,
>  					mask | IORESOURCE_PREFETCH, type);
>  	resource_size_t children_add_size = 0;
> +	resource_size_t max_align = 0, size0_max;
> +	int count = 0;
>  
>  	if (!b_res)
>  		return -ENOSPC;
> @@ -1016,19 +1020,59 @@ static int pbus_size_mem(struct pci_bus
>  			if (order > max_order)
>  				max_order = order;
>  
> +			count++;
> +			if (align > max_align)
> +				max_align = align;
> +
>  			if (realloc_head)
>  				children_add_size += get_res_add_size(realloc_head, r);
>  		}
>  	}
>  
> +	/*
> +	 * New rule: Prefer to small size instead of small align,
> +	 * when we have align/size: 1M/1M, 2M/2M,
> +	 *  min_align/size0: 1M/3M, max_align/size0_max: 2M/3M
> +	 *  pick 1M/3M.
> +	 * when we have align/size: 1M/1M, 64M/64M,
> +	 *  min_align/size0: 32M/96M, max_align/size0_max: 64M/65M
> +	 *  pick 64M/65M.
> +	 * when we have align/size: 1M/1M, 16M/64M,
> +	 *  min_align/size0: 8M/72M, max_align/size0_max: 16M/65M
> +	 *  pick 16M/65M.
> +	 * when we have align/size: 32M/64M, 128M/512M
> +	 *  min_align/size0: 64M/576M, max_align/size0_max: 128M/576M
> +	 *  pick 64M/576M.
> +	 * when we have align/size: 16M/32M, 128M/512M
> +	 *  min_align/size0: 64M/576M, max_align/size0_max: 128M/554M
> +	 *  pick 128M/554M.
> +	 * when we have align/size: 16M/64M
> +	 *  min_align/size0: 8M/64M, max_align/size0_max: 16M/64M
> +	 *  have to use 16M/64M.
> +	 */
>  	min_align = calculate_mem_align(aligns, max_order);
>  	min_align = max(min_align, window_alignment(bus, b_res->flags));
> +	max_align = max(max_align, window_alignment(bus, b_res->flags));
> +	if (count == 1)
> +		min_align = max_align;
> +
>  	size0 = calculate_memsize(size, min_size, 0, resource_size(b_res), min_align);
> +	size0_max = calculate_memsize(size, min_size, 0, resource_size(b_res),
> +					window_alignment(bus, b_res->flags));
> +
> +	if (size0_max < size0) {
> +		size0 = size0_max;
> +		min_align = max_align;
> +		max_align--; /* to use small align for size1 calculation */
> +	}
> +
>  	if (children_add_size > add_size)
>  		add_size = children_add_size;
>  	size1 = (!realloc_head || (realloc_head && !add_size)) ? size0 :
>  		calculate_memsize(size, min_size, add_size,
> -				resource_size(b_res), min_align);
> +				resource_size(b_res),
> +				min_align <= max_align ? min_align :
> +					window_alignment(bus, b_res->flags));
>  	if (!size0 && !size1) {
>  		if (b_res->start || b_res->end)
>  			dev_info(&bus->self->dev, "disabling bridge window %pR to %pR (unused)\n",

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Yijing Wang June 25, 2015, 1:59 a.m. UTC | #4 
>> Subject: [PATCH] PCI: Optimize bus mem sizing to small size
>>
>> Current code try to get min_align as possible and use that to
>> align final size.
>>
>> That could cause generate wrong align/size or too big size in some case.
>>
>>  when we have align/size: 16M/64M
>>  min_align/size0 will be 8M/64M, that is wrong, align must be 16M.
>>
>>  when we have align/size: 1M/1M, 64M/64M,
>>  min_align/size0 will be 32M/96M, that is way too big for sum size 65M.
>>
>> That will cuase allocation fails.
>>
>> The patch introduce max_align/size0_max, and size0_max is just
>> sum of all children resource.
>>
>> Prefer small size instead of small align. Only use min_align when
>> two size is the same.
>>
>> The new size will only need to be aligned to bus window alignment.
>>
>> Signed-off-by: Yinghai Lu <yinghai@kernel.org>
> 
> I'm sorry, I can't make any sense out of this.  I can't understand
> what you're trying to say.
> 
> A specific simple example might help.
> 
> Is this a regression?  Should it be marked for stable?  If so, how far
> back?
> 
> It doesn't apply on v4.1-rc2 (I would apply it manually if I could
> understand the changelog and comments, but you might as well refresh it at
> the same time as you rewrite those).
> 
> Please include a link to the problem report.
> 
> Please include the patch inline in the message.  It is a significant hassle
> for me to deal with attachments, and you are the only major contributor who
> uses them.


Hi Yinghai, do you have some updates for this patch ?
I open a bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=100451

I hope this fix could be merged in upstream.

Thanks!
Yijing.

> 
> Bjorn
> 
>> ---
>>  drivers/pci/setup-bus.c |   50 +++++++++++++++++++++++++++++++++++++++++++++---
>>  1 file changed, 47 insertions(+), 3 deletions(-)
>>
>> Index: linux-2.6/drivers/pci/setup-bus.c
>> ===================================================================
>> --- linux-2.6.orig/drivers/pci/setup-bus.c
>> +++ linux-2.6/drivers/pci/setup-bus.c
>> @@ -882,12 +882,14 @@ static void pbus_size_io(struct pci_bus
>>  	}
>>  
>>  	size0 = calculate_iosize(size, min_size, size1,
>> -			resource_size(b_res), min_align);
>> +				 resource_size(b_res),
>> +				 window_alignment(bus, IORESOURCE_IO));
>>  	if (children_add_size > add_size)
>>  		add_size = children_add_size;
>>  	size1 = (!realloc_head || (realloc_head && !add_size)) ? size0 :
>>  		calculate_iosize(size, min_size, add_size + size1,
>> -			resource_size(b_res), min_align);
>> +				 resource_size(b_res),
>> +				 window_alignment(bus, IORESOURCE_IO));
>>  	if (!size0 && !size1) {
>>  		if (b_res->start || b_res->end)
>>  			dev_info(&bus->self->dev, "disabling bridge window %pR to %pR (unused)\n",
>> @@ -962,6 +964,8 @@ static int pbus_size_mem(struct pci_bus
>>  	struct resource *b_res = find_free_bus_resource(bus,
>>  					mask | IORESOURCE_PREFETCH, type);
>>  	resource_size_t children_add_size = 0;
>> +	resource_size_t max_align = 0, size0_max;
>> +	int count = 0;
>>  
>>  	if (!b_res)
>>  		return -ENOSPC;
>> @@ -1016,19 +1020,59 @@ static int pbus_size_mem(struct pci_bus
>>  			if (order > max_order)
>>  				max_order = order;
>>  
>> +			count++;
>> +			if (align > max_align)
>> +				max_align = align;
>> +
>>  			if (realloc_head)
>>  				children_add_size += get_res_add_size(realloc_head, r);
>>  		}
>>  	}
>>  
>> +	/*
>> +	 * New rule: Prefer to small size instead of small align,
>> +	 * when we have align/size: 1M/1M, 2M/2M,
>> +	 *  min_align/size0: 1M/3M, max_align/size0_max: 2M/3M
>> +	 *  pick 1M/3M.
>> +	 * when we have align/size: 1M/1M, 64M/64M,
>> +	 *  min_align/size0: 32M/96M, max_align/size0_max: 64M/65M
>> +	 *  pick 64M/65M.
>> +	 * when we have align/size: 1M/1M, 16M/64M,
>> +	 *  min_align/size0: 8M/72M, max_align/size0_max: 16M/65M
>> +	 *  pick 16M/65M.
>> +	 * when we have align/size: 32M/64M, 128M/512M
>> +	 *  min_align/size0: 64M/576M, max_align/size0_max: 128M/576M
>> +	 *  pick 64M/576M.
>> +	 * when we have align/size: 16M/32M, 128M/512M
>> +	 *  min_align/size0: 64M/576M, max_align/size0_max: 128M/554M
>> +	 *  pick 128M/554M.
>> +	 * when we have align/size: 16M/64M
>> +	 *  min_align/size0: 8M/64M, max_align/size0_max: 16M/64M
>> +	 *  have to use 16M/64M.
>> +	 */
>>  	min_align = calculate_mem_align(aligns, max_order);
>>  	min_align = max(min_align, window_alignment(bus, b_res->flags));
>> +	max_align = max(max_align, window_alignment(bus, b_res->flags));
>> +	if (count == 1)
>> +		min_align = max_align;
>> +
>>  	size0 = calculate_memsize(size, min_size, 0, resource_size(b_res), min_align);
>> +	size0_max = calculate_memsize(size, min_size, 0, resource_size(b_res),
>> +					window_alignment(bus, b_res->flags));
>> +
>> +	if (size0_max < size0) {
>> +		size0 = size0_max;
>> +		min_align = max_align;
>> +		max_align--; /* to use small align for size1 calculation */
>> +	}
>> +
>>  	if (children_add_size > add_size)
>>  		add_size = children_add_size;
>>  	size1 = (!realloc_head || (realloc_head && !add_size)) ? size0 :
>>  		calculate_memsize(size, min_size, add_size,
>> -				resource_size(b_res), min_align);
>> +				resource_size(b_res),
>> +				min_align <= max_align ? min_align :
>> +					window_alignment(bus, b_res->flags));
>>  	if (!size0 && !size1) {
>>  		if (b_res->start || b_res->end)
>>  			dev_info(&bus->self->dev, "disabling bridge window %pR to %pR (unused)\n",
> 
> 
> .
>
Yinghai Lu June 25, 2015, 7:05 a.m. UTC | #5 
On Wed, Jun 24, 2015 at 6:59 PM, Yijing Wang <wangyijing@huawei.com> wrote:
>
> Hi Yinghai, do you have some updates for this patch ?
> I open a bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=100451
>
> I hope this fix could be merged in upstream.

Found problem with that patch on system with several bridges.

I am reworking allocation code.

Please check if you can test

git://git.kernel.org/pub/scm/linux/kernel/git/yinghai/linux-yinghai.git
for-pci-v4.2-rc1

on the setup.

It includes patches that support more smart bus align calculation and
alt_align etc.

Thanks

Yinghai
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Yijing Wang June 25, 2015, 7:25 a.m. UTC | #6 
On 2015/6/25 15:05, Yinghai Lu wrote:
> On Wed, Jun 24, 2015 at 6:59 PM, Yijing Wang <wangyijing@huawei.com> wrote:
>>
>> Hi Yinghai, do you have some updates for this patch ?
>> I open a bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=100451
>>
>> I hope this fix could be merged in upstream.
> 
> Found problem with that patch on system with several bridges.
> 
> I am reworking allocation code.
> 
> Please check if you can test
> 
> git://git.kernel.org/pub/scm/linux/kernel/git/yinghai/linux-yinghai.git
> for-pci-v4.2-rc1
> 
> on the setup.
> 
> It includes patches that support more smart bus align calculation and
> alt_align etc.

OK, I will look at it and try to test in local machine.

Thanks!
Yijing.

> 
> Thanks
> 
> Yinghai
> 
>
diff mbox

Patch

Subject: [PATCH] PCI: Optimize bus mem sizing to small size

Current code try to get min_align as possible and use that to
align final size.

That could cause generate wrong align/size or too big size in some case.

 when we have align/size: 16M/64M
 min_align/size0 will be 8M/64M, that is wrong, align must be 16M.

 when we have align/size: 1M/1M, 64M/64M,
 min_align/size0 will be 32M/96M, that is way too big for sum size 65M.

That will cuase allocation fails.

The patch introduce max_align/size0_max, and size0_max is just
sum of all children resource.

Prefer small size instead of small align. Only use min_align when
two size is the same.

The new size will only need to be aligned to bus window alignment.

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

---
 drivers/pci/setup-bus.c |   50 +++++++++++++++++++++++++++++++++++++++++++++---
 1 file changed, 47 insertions(+), 3 deletions(-)

Index: linux-2.6/drivers/pci/setup-bus.c
===================================================================
--- linux-2.6.orig/drivers/pci/setup-bus.c
+++ linux-2.6/drivers/pci/setup-bus.c
@@ -882,12 +882,14 @@  static void pbus_size_io(struct pci_bus
 	}
 
 	size0 = calculate_iosize(size, min_size, size1,
-			resource_size(b_res), min_align);
+				 resource_size(b_res),
+				 window_alignment(bus, IORESOURCE_IO));
 	if (children_add_size > add_size)
 		add_size = children_add_size;
 	size1 = (!realloc_head || (realloc_head && !add_size)) ? size0 :
 		calculate_iosize(size, min_size, add_size + size1,
-			resource_size(b_res), min_align);
+				 resource_size(b_res),
+				 window_alignment(bus, IORESOURCE_IO));
 	if (!size0 && !size1) {
 		if (b_res->start || b_res->end)
 			dev_info(&bus->self->dev, "disabling bridge window %pR to %pR (unused)\n",
@@ -962,6 +964,8 @@  static int pbus_size_mem(struct pci_bus
 	struct resource *b_res = find_free_bus_resource(bus,
 					mask | IORESOURCE_PREFETCH, type);
 	resource_size_t children_add_size = 0;
+	resource_size_t max_align = 0, size0_max;
+	int count = 0;
 
 	if (!b_res)
 		return -ENOSPC;
@@ -1016,19 +1020,59 @@  static int pbus_size_mem(struct pci_bus
 			if (order > max_order)
 				max_order = order;
 
+			count++;
+			if (align > max_align)
+				max_align = align;
+
 			if (realloc_head)
 				children_add_size += get_res_add_size(realloc_head, r);
 		}
 	}
 
+	/*
+	 * New rule: Prefer to small size instead of small align,
+	 * when we have align/size: 1M/1M, 2M/2M,
+	 *  min_align/size0: 1M/3M, max_align/size0_max: 2M/3M
+	 *  pick 1M/3M.
+	 * when we have align/size: 1M/1M, 64M/64M,
+	 *  min_align/size0: 32M/96M, max_align/size0_max: 64M/65M
+	 *  pick 64M/65M.
+	 * when we have align/size: 1M/1M, 16M/64M,
+	 *  min_align/size0: 8M/72M, max_align/size0_max: 16M/65M
+	 *  pick 16M/65M.
+	 * when we have align/size: 32M/64M, 128M/512M
+	 *  min_align/size0: 64M/576M, max_align/size0_max: 128M/576M
+	 *  pick 64M/576M.
+	 * when we have align/size: 16M/32M, 128M/512M
+	 *  min_align/size0: 64M/576M, max_align/size0_max: 128M/554M
+	 *  pick 128M/554M.
+	 * when we have align/size: 16M/64M
+	 *  min_align/size0: 8M/64M, max_align/size0_max: 16M/64M
+	 *  have to use 16M/64M.
+	 */
 	min_align = calculate_mem_align(aligns, max_order);
 	min_align = max(min_align, window_alignment(bus, b_res->flags));
+	max_align = max(max_align, window_alignment(bus, b_res->flags));
+	if (count == 1)
+		min_align = max_align;
+
 	size0 = calculate_memsize(size, min_size, 0, resource_size(b_res), min_align);
+	size0_max = calculate_memsize(size, min_size, 0, resource_size(b_res),
+					window_alignment(bus, b_res->flags));
+
+	if (size0_max < size0) {
+		size0 = size0_max;
+		min_align = max_align;
+		max_align--; /* to use small align for size1 calculation */
+	}
+
 	if (children_add_size > add_size)
 		add_size = children_add_size;
 	size1 = (!realloc_head || (realloc_head && !add_size)) ? size0 :
 		calculate_memsize(size, min_size, add_size,
-				resource_size(b_res), min_align);
+				resource_size(b_res),
+				min_align <= max_align ? min_align :
+					window_alignment(bus, b_res->flags));
 	if (!size0 && !size1) {
 		if (b_res->start || b_res->end)
 			dev_info(&bus->self->dev, "disabling bridge window %pR to %pR (unused)\n",