linux-kernel - Re: [PATCH 1/1] PCI: Don't print stale information about resource

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Message-ID: <20250924234828.GA2143336@bhelgaas>
Date: Wed, 24 Sep 2025 18:48:28 -0500
From: Bjorn Helgaas <helgaas@...nel.org>
To: Ilpo Järvinen <ilpo.jarvinen@...ux.intel.com>
Cc: Bjorn Helgaas <bhelgaas@...gle.com>, linux-pci@...r.kernel.org,
	linux-kernel@...r.kernel.org
Subject: Re: [PATCH 1/1] PCI: Don't print stale information about resource

On Wed, Sep 24, 2025 at 04:56:41PM +0300, Ilpo Järvinen wrote:
> pbus_size_mem() logs the bridge window resource using pci_info() before
> the start and end fields of the resource have been updated which then
> prints stale information.
> 
> Set resource addresses earlier to make understanding logs easier.
> Regrettably, this results in setting the addresses multiple times but
> that seems unavoidable.
> 
> Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@...ux.intel.com>

Applied to pci/resource for v6.18, thanks!

> ---
> 
> Based on top of pci/resource branch.
> 
>  drivers/pci/setup-bus.c | 15 ++++++++++-----
>  1 file changed, 10 insertions(+), 5 deletions(-)
> 
> diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c
> index d264f16772b9..362ad108794d 100644
> --- a/drivers/pci/setup-bus.c
> +++ b/drivers/pci/setup-bus.c
> @@ -1317,6 +1317,7 @@ static void pbus_size_mem(struct pci_bus *bus, unsigned long type,
>  	resource_size_t children_add_align = 0;
>  	resource_size_t add_align = 0;
>  	resource_size_t relaxed_align;
> +	resource_size_t old_size;
>  
>  	if (!b_res)
>  		return;
> @@ -1387,20 +1388,24 @@ static void pbus_size_mem(struct pci_bus *bus, unsigned long type,
>  		}
>  	}
>  
> +	old_size = resource_size(b_res);
>  	win_align = window_alignment(bus, b_res->flags);
>  	min_align = calculate_mem_align(aligns, max_order);
>  	min_align = max(min_align, win_align);
> -	size0 = calculate_memsize(size, min_size, 0, 0, resource_size(b_res), min_align);
> +	size0 = calculate_memsize(size, min_size, 0, 0, old_size, min_align);
>  
> -	if (size0)
> +	if (size0) {
> +		resource_set_range(b_res, min_align, size0);
>  		b_res->flags &= ~IORESOURCE_DISABLED;
> +	}
>  
>  	if (bus->self && size0 &&
>  	    !pbus_upstream_space_available(bus, b_res, size0, min_align)) {
>  		relaxed_align = 1ULL << (max_order + __ffs(SZ_1M));
>  		relaxed_align = max(relaxed_align, win_align);
>  		min_align = min(min_align, relaxed_align);
> -		size0 = calculate_memsize(size, min_size, 0, 0, resource_size(b_res), win_align);
> +		size0 = calculate_memsize(size, min_size, 0, 0, old_size, win_align);
> +		resource_set_range(b_res, min_align, size0);
>  		pci_info(bus->self, "bridge window %pR to %pR requires relaxed alignment rules\n",
>  			 b_res, &bus->busn_res);
>  	}
> @@ -1408,7 +1413,7 @@ static void pbus_size_mem(struct pci_bus *bus, unsigned long type,
>  	if (realloc_head && (add_size > 0 || children_add_size > 0)) {
>  		add_align = max(min_align, add_align);
>  		size1 = calculate_memsize(size, min_size, add_size, children_add_size,
> -					  resource_size(b_res), add_align);
> +					  old_size, add_align);
>  
>  		if (bus->self && size1 &&
>  		    !pbus_upstream_space_available(bus, b_res, size1, add_align)) {
> @@ -1416,7 +1421,7 @@ static void pbus_size_mem(struct pci_bus *bus, unsigned long type,
>  			relaxed_align = max(relaxed_align, win_align);
>  			min_align = min(min_align, relaxed_align);
>  			size1 = calculate_memsize(size, min_size, add_size, children_add_size,
> -						  resource_size(b_res), win_align);
> +						  old_size, win_align);
>  			pci_info(bus->self,
>  				 "bridge window %pR to %pR requires relaxed alignment rules\n",
>  				 b_res, &bus->busn_res);
> 
> base-commit: 43b4f7cd064b2ae11742f33e2af195adae00c617
> -- 
> 2.39.5
>